What happend to 320K resistors ? - Page 1
Forum section: electronics / general

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 19, 2021, 03:42:38 pm
content: Hi, something happend in resistor land.I can not get 320K metal resistors anymore ( for a normal price )Why did they stop making those ?

author: AndyC_772
author_rank: Super Contributor
timestamp: February 19, 2021, 03:45:03 pm
content: 320K is E192 range - pretty obscure values, and there's bound to be some values for which there simply isn't the demand.Can you not use 316K instead? That's E48, should be more readily available.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 19, 2021, 03:50:18 pm
content: The thing is i like to make a 6-bit DAC :5K10K20K40K80k160k320k

author: bdunham7
author_rank: Super Contributor
timestamp: February 19, 2021, 03:56:59 pm
content: https://www.mouser.com/ProductDetail/Vishay-Dale/CMF55320K00BER6/?qs=OCLsGa2zKBtCzF2AhImE2w%3D%3D

author: vad
author_rank: Frequent Contributor
timestamp: February 19, 2021, 03:57:32 pm
content: Use two 160k (E24) resistors in series.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 19, 2021, 03:58:37 pm
content: Mouser sell them. e.g.,https://www.mouser.com/ProductDetail/Yageo/RT0603DRD07320KL/?qs=ABvmyp11KkhJ2c1FEjGD5A%3D%3DOr you could just use 316 + 1 + 1 + 1 + 1?

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 19, 2021, 03:59:29 pm
content: I dont have anything SMD, searching for normal axial resistors.Soldering more resistors is not the plan, i still have some 320K resistors, i want more.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 19, 2021, 04:02:05 pm
content: if i buy 100 of those 50 cent resistors, i have instant free shipping.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 19, 2021, 04:02:23 pm
content: See bdunham7's answer. It's axial.

author: wraper
author_rank: Unknown
timestamp: February 19, 2021, 04:04:22 pm
content: Buy 316k, that's only 1.25% difference. Unless you need extreme precision.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 19, 2021, 04:09:40 pm
content: Ofcourse i want the precision for a DAC,because i could buy them some time ago i dont want those 316K.They just disapear ?, someone has buyed them since they have nothing left.Why not make a few to keep stock ?, is it so difficult ?

author: bdunham7
author_rank: Super Contributor
timestamp: February 19, 2021, 04:12:38 pm
content: Exactly what were you buying before that you can't get now? Are the ones I posted not what you need??? Other than '320K' what are the rest of the specs you need or had?

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 19, 2021, 04:20:20 pm
content: Quote from: Jan Audio on February 19, 2021, 04:09:40 pmMouser has them. Granted, it's overseas but you have a very specific requirement so your options are going to be limited.Alternatively, buy a lot of 10% or 20% 330K and measure each one. One will be 320K.

author: nali
author_rank: Frequent Contributor
timestamp: February 19, 2021, 04:26:03 pm
content: Quote from: Jan Audio on February 19, 2021, 04:09:40 pmJust wondering, why do you need such precision when you only have 6 bits anyway?

author: Siwastaja
author_rank: Super Contributor
timestamp: February 19, 2021, 04:32:27 pm
content: What's wrong with the classic R2R DAC that uses a single value of resistor?What's wrong in putting another resistor in series?How are you driving your resistor DAC? From standard CMOS outputs of an MCU or logic IC?I think the problem isn't sourcing 320kOhm resistors; it's designing a DAC. Let's start by defining your requirements for the DAC.

author: asmi
author_rank: Super Contributor
timestamp: February 19, 2021, 05:19:53 pm
content: Quote from: Siwastaja on February 19, 2021, 04:32:27 pmI would add one more question - what's wrong with people designing in thru-hole passives in year 2021?

author: srb1954
author_rank: Super Contributor
timestamp: February 19, 2021, 07:40:03 pm
content: Quote from: nali on February 19, 2021, 04:26:03 pmAnd why get so concerned about a little bit of error in the resistor value for the LSB of the DAC?You are going to need some very precise resistors for the MSB of the DAC before the error in the LSB value is even going to be noticeable.

author: srb1954
author_rank: Super Contributor
timestamp: February 19, 2021, 07:51:25 pm
content: Quote from: Jan Audio on February 19, 2021, 04:09:40 pmIt is actually quite difficult for the distributors and manufacturers to deal with the demand for with rarely ordered values.A distributor is not going to want to keep a reel of very slow moving resistors on the shelf just for the occasional low volume purchaser. The solderability of components deteriorates over time so the distributor is only going to stock items that can be turned over every 6 months or faster.The manufacturer is going to have the same problem. They are not going to keep an obscure value on the shelf just in case some distributor orders it out of the blue. More likely they will manufacture the value to order and then they will want to manufacture considerably more than a one reel quantity to justify the set-up costs for that production.

author: coppercone2
author_rank: Super Contributor
timestamp: February 20, 2021, 03:14:04 am
content: axial resistors kick asswhat suppliers get for stocking e196 is1) people buying more parts in general in the first theme because they can get anything they need in the same kind for uniform designs, its not that much room considering the size of these places, give me a break. you need them for some engineering designs, stop forcing SMD on people for no reason other then its cheaper or desirable for YOUR process.. stop thumping the 'new testament' of SMD being better at everything, not everyone wants rice. People keep pushing vibration but there is also flex2) respect

author: wraper
author_rank: Unknown
timestamp: February 20, 2021, 03:19:44 am
content: Quote from: coppercone2 on February 20, 2021, 03:14:04 amSMD is not only cheaper but also takes less space, is faster to assemble and have less of parasitic inductance. Not to say TH parts go away, you simply cannot find most of modern parts in TH.

author: coppercone2
author_rank: Super Contributor
timestamp: February 20, 2021, 03:21:26 am
content: and whats the flex resistance of a 1206?? stiff as a man dead 2 weeks. all people keep pushing is vibration resistance and inductance, try failure mode, inspection, repair, flex,and you can use heat sink clips nice on through holes to HIGH effect and have easy probing with the most basic of grabbers without a lab setup. you can hook on to them upside down in a panel with a flash light on your head if you wanted to while your being held upside down on a rope no problem.

author: james_s
author_rank: Super Contributor
timestamp: February 20, 2021, 03:23:11 am
content: Quote from: asmi on February 19, 2021, 05:19:53 pmThis does strike me as a bit strange. I still use them for prototyping occasionally, and might consider it for a kit aimed at total beginners but otherwise there are few reasons to use small through hole resistors. There's always the huge chunky 1206 surface mount parts for people that have poor eyesight or shaky hands.

author: wraper
author_rank: Unknown
timestamp: February 20, 2021, 03:26:37 am
content: Quote from: coppercone2 on February 20, 2021, 03:21:26 amWho sane uses 1206 other than for parts which must be large? Even 0805 is too large for most passives.

author: coppercone2
author_rank: Super Contributor
timestamp: February 20, 2021, 03:27:22 am
content: 1/4 wattyou want a 1/4 watt smd you get 1210 minimum , depending on what your customers believe1206 is 1/8 my bad

author: wraper
author_rank: Unknown
timestamp: February 20, 2021, 03:33:08 am
content: Quote from: coppercone2 on February 20, 2021, 03:27:22 amYou can buy 0.3W in 0805. In 1206 you can get up to 1W. And you don't need 1/4W in 99% of cases, 1/16W or 1/8W is more than enough usually. Just because small TH resistors usually come with 1/4W rating does not mean you actually need it.

author: coppercone2
author_rank: Super Contributor
timestamp: February 20, 2021, 03:35:00 am
content: link to 300mW 0805 320k thin film?

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2021, 07:15:51 am
content: You need to realize TH technology is mostly obsolete, want it or not. So no matter how much you prefer TH over SMT, no matter how good reasons you have, the selection of parts available is poor and gets worse every day. You can whine about it until cows come home, or you can just use the parts that are available and get the job done. Side effects are almost all positive, but attitude needs to be fixed first.My observation is that people who most whine about lack of TH parts are those who have no idea about circuit design and their designs would fail even if all the parts in the world would be available in TH. As always, coming up with excuses is a sign of something.

author: ogden
author_rank: Super Contributor
timestamp: February 20, 2021, 07:44:28 am
content: Quote from: Siwastaja on February 20, 2021, 07:15:51 amYour observation is correct. People who have no idea about circuit design do exist. They are beginners. Even today it is nothing wrong about using breadboard or learning circuit design using through hole components and perfboard.Thou beginners shall listen too. If many people are telling you that your approach is wrong - then most likely it is so. In this case apply best engineering practices - use your head and parts that are available (E24):300 + 20 = 320 (0 %)220 + 100 = 320 (0 %)200 + 120 = 320 (0 %)160 + 160 = 320 (0 %)calc used:https://www.qsl.net/in3otd/parallr.html

author: srb1954
author_rank: Super Contributor
timestamp: February 20, 2021, 08:40:35 am
content: Quote from: wraper on February 20, 2021, 03:19:44 amSMD may have some advantages for non-critical applications but it has some severe disadvantages in high power circuitry:The power handling capability for pulse loads for most types of SMD resistors is abysmalThe ability of SMD resistors to withstand high peak voltages is poorThe ability to withstand thermal cycling stress with pulsed loads is poor, especially when using lead-free solderIf the application requires power dissipations more than several watts the heating of the PCB material and surrounding components becomes excessive with SMD partsIf any of the above situations applies the best option is often to stick with leaded parts.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2021, 08:58:11 am
content: Quote from: srb1954 on February 20, 2021, 08:40:35 amAlso large capacitors and connectors benefit from the mechanical support you get with THT.90-99% of parts in such designs are still likely SMD. The control side tends to have large number of components, especially large number of pins.It's not a choice whether to build the entire thing in THT or SMT, that would be stupid.Right component is used for the job, each component chosen separately based on what is needed.Fully SMT designs are rare in power electronics. Fully THT are even more rare.It's all about availability and suitability. If you want a modern microcontroller, there is no TH type available. If you want a 10000uF 50V capacitor, there is no SM type available. If you have decided not to use certain technology for no good reason, you can't do the job because you need both types.

author: ogden
author_rank: Super Contributor
timestamp: February 20, 2021, 09:42:15 am
content: Quote from: srb1954 on February 20, 2021, 08:40:35 amLimiting factor is PCB heat handling properties, not SMT resisors as such. 35W SMT resistor for example: RHFH4Q050R0FE. If you need smaller heater on your PCB, then consider Vishay RCP series or similar.Low voltage rating of small SMT resistors is due to their (surprise surprise!) size. Simple solution - put multiple resistors in series or use higher voltage rating SMT resistors, usually both. Open parametric search of your parts distributor and see for yourself - plenty of choices.

author: ogden
author_rank: Super Contributor
timestamp: February 20, 2021, 09:47:25 am
content: Quote from: Siwastaja on February 20, 2021, 08:58:11 amStupid would be to not try to build entire thing using SMT only. To state obvious: THT is added cost. Here I talk about electronics manufacturing in general.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2021, 09:57:25 am
content: Yes, I always try to default to full-SMT design whenever possible. The opposite, trying to default to THT, is becoming a masochistic act I think.At some point I realized that TH parts isn't as much extra cost you could think it is. If you do a proto batch of 10, just solder them yourself, takes an hour. If you do 100, let the Chinese CM solder them for you. What I have seen, the quality is OK.So I don't feel bad using TH parts when there is an advantage, for example the large caps, bulky connectors and high power resistors, high voltage parts. And TH pin header takes less board area than SMD pin header.BTW regarding resistors that dissipate a lot, sometimes this is a sign of bad circuit design. Always when dissipating power, ask the fundamental question, why do you need to dissipate? Sometimes you can just make the circuit more efficient, save space, assembly cost,andenergy. For example, instead of dissipating 5W in a current measurement resistor, use a higher gain, lower offset amplifier and dissipate only 1W. Or instead of "regulating" current by CV supply + series resistor, design a CC supply.

author: langwadt
author_rank: Super Contributor
timestamp: February 20, 2021, 10:52:35 am
content: Quote from: wraper on February 20, 2021, 03:33:08 amthey don't exactly give them away but digikey has plenty 0.4W, 0.5W and some 1.5W 0603

author: ebastler
author_rank: Super Contributor
timestamp: February 20, 2021, 12:48:16 pm
content: Quote from: Jan Audio on February 19, 2021, 03:59:29 pmBit stubborn, are we?I guess you have two plausible options:(a) Take one of the various recommendations given in this thread, or(b) keep searching for 320k resistors, quietly please.Digging in your heels here in the forum until someone makes 320k resistors for you is not one of them, I'm afraid.

author: TimFox
author_rank: Super Contributor
timestamp: February 20, 2021, 02:57:21 pm
content: Just an important mathematical point:The "E" series of component values, which are very common for resistors, split each decade into approximately equal (ratio) increments, so that if a valueRexists, then so shall 10 xR. (Analogous to the tempered division of octaves in piano tuning.) Your requirement uses resistors that are in a binary power sequence, proportional to 2N. Obviously, at some point the binary sequence will reach a value not in the E sequence. Therefore, it seems prudent to include the capability of two resistors in series (or parallel) at some places to obtain the values needed.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 20, 2021, 02:57:41 pm
content: Quote from: ebastler on February 20, 2021, 12:48:16 pmDont forget for cheaper then 50 cent, not wanto pay more then 5 max.Quote from: srb1954 on February 19, 2021, 07:51:25 pmThank you, i did not know this was a problem, i thought those resistors stay good forever.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 20, 2021, 03:07:29 pm
content: Quote from: asmi on February 19, 2021, 05:19:53 pmI like the 80s better.80s tech is my favourite.I want to invest in SMD this year, if only i had as much money as i have thru-hole parts.I like being a hobbyist, not a professional.With SMD you are no hobbyist i think.

author: wraper
author_rank: Unknown
timestamp: February 20, 2021, 03:20:44 pm
content: Quote from: coppercone2 on February 20, 2021, 03:35:00 amWhy would you want 320k thin film (for which op did not even ask) in 0.3W? You would need to apply 309V on such resistor to get 0.3W dissipation. And it would be a lot more than max allowed voltage for resistor in such package.Here is usual 330khttps://www.tme.eu/en/details/hp05-330k1%25/0805-smd-resistors/royal-ohm/hp05w3f3303t5e/

author: wraper
author_rank: Unknown
timestamp: February 20, 2021, 03:31:39 pm
content: Quote from: Jan Audio on February 20, 2021, 03:07:29 pmSo far from truth. Hobbyists use SMD a lot. Especially considering they can order PCBs for a few bucks. Are you professional if you are reflowing PCBs on a pan?

author: daqq
author_rank: Super Contributor
timestamp: February 20, 2021, 03:35:04 pm
content: I'm not sure what the problem is - you were relying on a part that was fairly obscure even in its heyday. The market for obscure non-SMD resistor values is simply not that large and explains why it's no longer an option.Several suggestions here solve your problem, all of which you have refused for silly reasons.QuoteWrong.

author: bdunham7
author_rank: Super Contributor
timestamp: February 20, 2021, 03:39:18 pm
content: Quote from: Siwastaja on February 20, 2021, 07:15:51 amActually I'm continually amazed at what is available still. In repairing stuff from 100 years old to 3 years old, I actually run into more obstacles with obsolete SMT parts than I do TH. And in repair, I often have less flexibility, although I generally don't quibble about cost. I can get brand new 12AU7 dual triodes from several manufacturers, but a relatively common MP2363DN buck converter is obsolete, although there are some still out there. I'd have to stockpile them if I thought I would need more.QuoteTo a novice, TH might seem easier until they have to lay out a space-constrained board and they realize that a TH PDIP will obstruct all the layers of the board.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 20, 2021, 03:56:06 pm
content: Quote from: daqq on February 20, 2021, 03:35:04 pmThe reason is i already have those parts.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 20, 2021, 04:04:25 pm
content: Quote from: bdunham7 on February 20, 2021, 03:39:18 pmStockpiling obsolete parts is a serious thing in this hobby, and you can make good money also if you buy enough.

author: bdunham7
author_rank: Super Contributor
timestamp: February 20, 2021, 04:06:27 pm
content: Quote from: Jan Audio on February 20, 2021, 03:56:06 pmWhat tolerance are your other parts? It makes no sense to have this value at any tolerance greater than 1%.How many of these 6-bit DACs are you making that cost is such a concern?

author: Kleinstein
author_rank: Super Contributor
timestamp: February 20, 2021, 04:07:49 pm
content: The main use for THT parts is for test circuit on the bread board or manybe perf board and a few higher power parts. With a PCB it is much easier to use SMD parts and build to oder PCBs have become relatively cheap.It does not take much practice to solder 0805 resistors and caps and 0603 as also not hard. One used to it one hardly wants back to THT, even on a perf board.Especially for DAC and 1:2:...:32 resistors it is absolte normal to combine 2 resistors , as this reduces the number of unique parts. I would even consider just 2 values and us each as 2 in parallel, as a single and 2 in series. The 320 K resistor in the circuit is the least critical, so 314 K and maybe even 330 K should be good enough.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 20, 2021, 04:10:47 pm
content: Quote from: Jan Audio on February 20, 2021, 03:56:06 pmTrying to design around what you have is all fine, but you tend to run in trouble as soon as you are building more than you originally expected and run out of those "free" parts.For this reason even though I like using my existing stock, I'm very careful when doing that so that I don't need to redesign suddenly.Using your own stock works as long as you know the parts are either easily orderable with product lifetime left, or generic enough to have acceptable replacements.Most components are very cheap; I just buy new components by default, and use excess stock for one-offs and prototypes where I know I'll only build that one piece.BTW most good practices are the same regardless of being a professional or a hobbyist. For example, you want your circuit to work nevertheless. Similarly, you want to use parts that are available. And miniatyrization, often a professional product can be arbitrarily large, or a hobby project needs to be small, or vice versa.

author: bdunham7
author_rank: Super Contributor
timestamp: February 20, 2021, 04:18:06 pm
content: Quote from: Jan Audio on February 20, 2021, 04:04:25 pmOh I know--I recently bought 10 resistors for $5 each plus an hours drive to get them and I was quite happy to be able to acquire them. But that is for a repair scenario where there aren't good alternatives. If it was something I was making, I'd try to use parts with good availability.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 20, 2021, 04:25:32 pm
content: $50 for 10 resistors,you make me think those $50 ( excl. tax ) for 100 resistors are worth it.For $50 i build a whole synthesizer.

author: Monkeh
author_rank: Super Contributor
timestamp: February 20, 2021, 04:27:00 pm
content: Or you could just alter your design and use series and parallel combinations of more common values to get the desired value instead of whining about how hard it all is.

author: james_s
author_rank: Super Contributor
timestamp: February 20, 2021, 07:40:13 pm
content: Quote from: Jan Audio on February 20, 2021, 03:07:29 pmI've been using SMD as a hobbyist for at least 15 years. 10 years ago I was etching my own PCBs using toner transfer and routinely using 0603 passives and SOIC chips. I was even able to achieve 0.5mm pitch ICs on self etched boards but that was pushing the process to the limit and was difficult. SOIC though was easy. I can also prototype with SOIC and 0805 passives "Manhattan" style on bare copperclad, and the passives fit nicely soldered between two pads of a normal 0.1" protoboard.I don't understand the comments about investment, what do you need to invest in? The components are cheap as dirt, you can buy 100 SMD resistors for under $1, they're significantly cheaper than through hole. You don't need much in the way of special tools, I use a $3 set of tweezers and my regular soldering iron. A syringe of liquid flux is helpful at times too.I remember many years ago people moaning that SMT had killed the electronics hobby. I thought it strange because I never noticed, the transition was almost painless, I didn't throw out my through-hole stuff, I just gradually incorporated more and more SMD as time went on and that's what was available. It wasn't hard, I didn't need any special skills or training, just a few new techniques. It didn't take long for me to prefer SMT because it saved having to drill all those holes.

author: floobydust
author_rank: Super Contributor
timestamp: February 20, 2021, 08:44:31 pm
content: The EE generation following us can't use a breadboard anymore, they are obsolete. Through-hole is dying out it was King for experimenting and learning electronics. Now, getting a pcb made, unsoldering a SMT part and flicking it across the bench and putting in a new one, well- not so much fun. And I need a magnifying lens now with old eyes.For hobby/home products, personal preference, I use through-hole for power stuff, it's not yet a crime. Just easier to work with.SMT is when a design is stable and I'm able to solder in the IC's. They are constantly getting smaller, no pins, finer pitch. Soon it will be machine assembly only.But audio can get a bit weird with people discussing "the sound of resistors" instepped attenuatorsand DACs, some prefer through-hole i.e.Holco"... original Meggitt Holsworthy, UK made resistors. They give a crisp, full sound, superb."I just think it's psycho-acoustics or the RF properties (greater self-inductance), big metal film through-hole has a following it seems.

author: John B
author_rank: Frequent Contributor
timestamp: February 20, 2021, 08:56:20 pm
content: Seems like hobbyists have the best of both worlds, where you can utilise SMD for compactness, lower cost and better preservation of a ground plane, while still not being constrained by manufacturing labour costs that would prohibit manual installation of through hole stuff. I still prefer TO-220 devices on heatsinks, and even use *gasp* the odd high current jumper.

author: ogden
author_rank: Super Contributor
timestamp: February 20, 2021, 11:03:21 pm
content: Quote from: floobydust on February 20, 2021, 08:44:31 pmIt's like saying that computer music will obsolete piano play and 3d printers will obsolete LEGOJust one of many examples why breadboard is far from dying and next generations will use such or alike:https://www.amazon.com/s?k=arduino+starter+kit

author: srb1954
author_rank: Super Contributor
timestamp: February 21, 2021, 01:09:57 am
content: Quote from: ogden on February 20, 2021, 09:42:15 amOf course the limiting factor is the ability for the PCB to handle the heat but by just blindly insisting on using SMT resistors isn't going to suddenly make the PCB perform better; it will just make the problem worse. Just because the letters SMT appear on the datasheet it it doesn't mean you can magically bypass the laws of physics.If you actually read the datasheet for the suggested RHFH4Q050R0FE resistor you will see that it needs a heatsink to dissipate its rated power. In fact it needs a massive heatsink of 0.4degC/W to achieve its rated power even if you limit the maximum ambient temperature to a paltry 25C. Without the heatsink, and mounted on the recommended PCB footprint, this resistor is only good for 2W dissipation and should have been advertised as such rather than the practically unobtainable figure of 35W.Similar comments apply to the suggested Vishay RCP parts. These are also heavily reliant on the heatsinking effect of the PCB to achieve their apparent high power ratings. Just sticking the part down on a bit of FR4 is not going to led to success. Unfortunately the datasheet offers no guidance on how to heatsink these resistors and it is left to the circuit designer to sort out the thermal engineering issuesThe advantage of using leaded components in these situations is that the component manufacturer has already done most of the thermal engineering work for you. If you mount the leaded component in accordance with the manufacturer's recommendations and not restrict the air flow around it you can pretty much expect it to perform as advertised without having to put in a lot of effort into thermal engineering issues. With leaded components quite a bit of the heat is taken away by convection before it reaches the PCB so the PCB material and surrounding components run cooler.Thermal engineering can be one of the most difficult aspects of product design and unfortunately most circuit engineers neither have the knowledge or experience to be proficient in thermal engineering issues. If this thermal engineering it not done properly the product can fail on the market due to unreliability, short lifetime or product warranty costs. Even with an experienced designer thermal engineering can be very expensive in terms of the engineering time and product development timetable.Quote from: ogden on February 20, 2021, 09:42:15 amIt's not that simple.If your circuitry using using fast pulse waveforms then you have to be very concerned about unequal voltage sharing across a string of resistors due to circuit parasitic capacitances and inductances. In some cases you even have to put balancing capacitors across each resistor to force equal sharing of pulse voltages. This requires extra engineering time not to mention the extra cost of additional BOM items, assembly and test time and additional PCB area.Again, using a single leaded part is often a much better solution. The component manufacturer has done all the hard work of characterising the component under the pulse operating conditions and all the circuit designer has to do is follow the manufacturer's mounting recommendations to successfully use the product.

author: floobydust
author_rank: Super Contributor
timestamp: February 21, 2021, 05:35:41 am
content: Quote from: ogden on February 20, 2021, 11:03:21 pmThe piano is getting smaller every day but our fingers are the same size. It's the workability of SMT that make it difficult and new parts are not offered in anything but through-hole, for years now.

author: coppercone2
author_rank: Super Contributor
timestamp: February 21, 2021, 06:07:06 am
content: and.. probes cost how much? Dip clip, wonderful. You can do soic but its a little janky, but any resistor or whatever is a total pain in the ass requiring new equipment that takes up alot of room (positioning arms etc)

author: ogden
author_rank: Super Contributor
timestamp: February 21, 2021, 09:19:28 am
content: Quote from: srb1954 on February 21, 2021, 01:09:57 amYour claim is true for leaded resistors up-to certain power level only. Show me "already done thermal enginering" of this 35W through-hole resistor: PWR220T-35-50R0J It is not fault of SMT resistor that some can't do thermal engineeringIf you actually look for it, you can find pre-existing thermal engineering (appnotes) for SMT power resistors. Just an example:https://www.vishay.com/docs/53047/pra-appn.pdf,https://www.vishay.com/docs/53048/pprachp.pdfQuoteJust search and you will find 10KV SMT resistors. Evenprecision low TC partsif needed. Argument could be price, but not as you say "use leaded parts. period."Fact that you can think of >1KV edge case where even leaded components require careful engineering does not prove your initial blanket statement. Most of applications where one shall start to think about SMT resistor voltage rating and chaining are AC mains. SMT resistors are fine and widely used in such.

author: ogden
author_rank: Super Contributor
timestamp: February 21, 2021, 09:31:43 am
content: Quote from: floobydust on February 21, 2021, 05:35:41 amIf you want to use modern, highly integrated ICs then be ready to face consequences. When you introduce modern IC, you have to introduce modern way of engineering too. Other option - use old parts or 3rd party DIP conversion adapters/modules.

author: GlennSprigg
author_rank: Super Contributor
timestamp: February 21, 2021, 11:37:48 am
content: All this reminds me of my Security Systems days, where there areEOL(End Of Line) Resistors, next tothe field sensors / reed switches etc., and the electronic control system needed to see aVERYspecificresistive value, that was not only uncommon, (like 273k or what ever, made up!), but very difficult to even simulatewith a bunch of series/parallel resistors!Most (lazy) installers often put them in the control panel!! so totally negating their use!!For interest... All higher level systems (Govt places, prisons etc.) utilize a "1-pair-in-the-world" IC Chipepoxy-moulded into the field 'sensor/etc), and the other sole matching IC in the master control panel,just for that individual zone/sector. There's no way to fool them in the field!!

author: Siwastaja
author_rank: Super Contributor
timestamp: February 21, 2021, 01:27:13 pm
content: Quote from: ogden on February 21, 2021, 09:31:43 amIn general, modern parts are so much better and so much easier to use. With external component count going down and integration level going up, there is often much less soldering to do with modern parts. So the "consequence" is often positive despite the initial "this must be hard" attitude.The sweet spot is finding what you need in relatively "easy" SMD packages like SOIC, SOT-23 etc. QFN, BGA, CSP suck with no-PCB prototyping but still, if a really good and otherwise easy-to-use part is available only in such packages, I wouldn't be afraid of using them, just bite the bullet.It's really strange to see this "SMD is not for hobbyists" discussion in 2021! This was a common theme back some 10-20 years ago, and all but gone for the last 5 years or so.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 21, 2021, 03:10:17 pm
content: I am sorry to say the SOIC parts are almost obsolete already.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 21, 2021, 03:18:11 pm
content: I always imagine what kind of super chip a 40-pin 8-bitter could be in all that space compared to the smallest part available that is the same.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 21, 2021, 03:21:51 pm
content: Quote from: floobydust on February 20, 2021, 08:44:31 pmThey need to invent a magnetic-breadboard somehow.I do agree with you, all those "breadboard-less people" have a windows 10 spyware computer with the latest simulators that i dont trust somehow.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 21, 2021, 03:25:59 pm
content: Quote from: Jan Audio on February 21, 2021, 03:21:51 pmWhich don't you trust? The "breadboardless-people", Windows 10 or the latest simulators?

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 21, 2021, 04:01:26 pm
content: The magnetic-breadboard.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 21, 2021, 04:42:29 pm
content: Quote from: Jan Audio on February 21, 2021, 03:10:17 pmNo! SOIC packages are widely used in analog (opamps, comparators), logic gates, ADCs/DACs, gate drivers, SMPS controllers and regulators, and so on...Modern microcontrollers tend to use packages which give larger number of pins in smaller space, though. While SOIC is quite a miniaturization compared to DIP, it's still huge on today's terms.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 21, 2021, 04:43:00 pm
content: Quote from: Jan Audio on February 21, 2021, 03:21:51 pmDon't want to sound harsh, but are you on drugs?

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 21, 2021, 04:45:10 pm
content: Quote from: Siwastaja on February 21, 2021, 04:42:29 pmI could only find some EOL audio DACs in SOIC.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 21, 2021, 04:45:54 pm
content: Quote from: Siwastaja on February 21, 2021, 04:43:00 pmMaybe to strong weed, no drugs.What did you not take serious ?You trust simulators ?You say win10 is not spyware ?You say breadboardless people dont exist ?All together ?

author: Monkeh
author_rank: Super Contributor
timestamp: February 21, 2021, 04:55:35 pm
content: Quote from: Jan Audio on February 21, 2021, 04:45:54 pmBecause THC isn't a drug, just like ethanol and caffeine.QuoteThose who understand their usage and limitations trust them within those confines.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 21, 2021, 04:58:19 pm
content: I just don't see the connection from SMD components to Windows 10, but I'm a boring engineer not on drugs. Maybe THC helps creating such interesting connections. I don't say this is a bad thing.And yes, I "trust" simulators. Just don't blindly. They are tools you need to understand. Really helpful tools. Designing without one is also a masochistic act.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 21, 2021, 05:03:05 pm
content: So you simulate and send to factory ?Sounds breadboardless.I agree that my designs take at least a full year to complete, i better call it patience.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 21, 2021, 05:19:53 pm
content: Prototyping highly recommended. Fully simulating for all aspects takes more time than using the best tool for the job, which often is a physical prototype.I personally do not like solderless breadboards, they are source of extra problems I don't want; even if you use highest-quality 3M breadboards and be careful not to damage them, they greatly limit the types of components you can insert. Instead, learn to be proficient with soldering iron, then you can quickly prototype any types of parts, SMD and THT included, without wonky and unreliable connections. Google "Manhattan style prototyping" for pictures.Sometimes there is no work for a SPICE simulator. For example, a circuit running an MCU interfacing a digital temperature sensor and showing the number on 7-segment display, nothing interesting in analog domain going on you would want to simulate. With such simple example, if you are even a bit experienced, you won't need to Manhattan prototype it, just draw and order 5pcs PCBs, 90% chances you can just start producing it as-is, 10% you made some stupid mistake which you'll fix to the final revision.Patience is good. Quick iteration cycle is still goodevenif you have a lot of time in your hands - you can run more cycles and get even better product.

author: ebastler
author_rank: Super Contributor
timestamp: February 21, 2021, 07:08:04 pm
content: Quote from: Jan Audio on February 21, 2021, 04:45:10 pmMouser shows me 27 different audio DACs in SOIC packages which (according to their database) are active products. Quite a few different types are in stock.Not sure how long-lived the link to the search results will be, but here it is:https://www.mouser.de/Semiconductors/Integrated-Circuits-ICs/Audio-ICs/Audio-D-A-Converter-ICs/_/N-6j741Zgjdhub?P=1z0yhi1Z1z0z5fdZ1z0z7v5Edit: Oh, and did I mention 130 audio DACs in SSOP/TSSOP packages, which can be drag-soldered by hand with a regular iron as well?

author: Zero999
author_rank: Super Contributor
timestamp: February 21, 2021, 07:39:59 pm
content: Quote from: Jan Audio on February 19, 2021, 03:50:18 pmWhy do you need those resistor values in a DAC?

author: ogden
author_rank: Super Contributor
timestamp: February 21, 2021, 07:43:38 pm
content: Quote from: Siwastaja on February 21, 2021, 05:19:53 pmRight. Breadboards are great for beginners to play and learn. That's main purpose of them. Professionals will find parasitics of breadboards and jumper wires limiting. Tho my usual approach of quick weekend prototype (if any) - use stm32 blue pill module together with prototype circuit board on perfboard/manhattan/custom_PCBa, use breadboard as carrier and interconnect for modules. If I need some faster signal between MCU on bluepill and prototype circuit - use soldered wire or TP or coax, maybe even remove corresponding DIP pin on bluepill. Hint: get more than single bluepill/arduino and acompanying breadboard. You may have multiple ideas in parallel

author: Vovk_Z
author_rank: Super Contributor
timestamp: February 21, 2021, 08:06:14 pm
content: Quote from: Jan Audio on February 19, 2021, 03:50:18 pmThat can be made from three nominals: 5k is 2x10k in parallel.Then 20k in parallel ( it is 10k).Then 20k.Then 20k in series.Then 160k in parallel.Then 160k.Then 160k in series.So we'll need only three popular values: 10k, 20k and 160k. Some of them exist in E24, some in E48, some in E96, and all are in E192.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 22, 2021, 02:29:45 pm
content: For SMD people its easy to advice something like that.

author: Monkeh
author_rank: Super Contributor
timestamp: February 22, 2021, 02:34:00 pm
content: Quote from: Jan Audio on February 22, 2021, 02:29:45 pmIt's no harder with through hole. You could have fixed it easily by now.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 22, 2021, 02:50:31 pm
content: Quote from: Jan Audio on February 22, 2021, 02:29:45 pmSeriously, how hard is this?

author: bdunham7
author_rank: Super Contributor
timestamp: February 22, 2021, 03:06:07 pm
content: Quote from: JohnnyMalaria on February 22, 2021, 02:50:31 pmI don't know about the OP, but for the typical OCD-addled audiophile type that would trigger a meltdown that would require months of therapy."The soundstage is clearly bifurcated...."

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 22, 2021, 03:26:23 pm
content: I only wanted to know why 100 resistors cost more then 50 euro without tax.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 22, 2021, 03:28:57 pm
content: Why 100?

author: bdunham7
author_rank: Super Contributor
timestamp: February 22, 2021, 03:37:39 pm
content: Quote from: Jan Audio on February 22, 2021, 03:26:23 pmIf you are referring to the ones I posted, it is because they are 0.1% 25PPM/C industrial-grade precision resistors.What exact part number were you using previously that you can't get now?

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 22, 2021, 04:33:45 pm
content: I dont know.Why 100 ?, i buy per 100 or 1000.

author: TimFox
author_rank: Super Contributor
timestamp: February 22, 2021, 04:57:05 pm
content: Quote from: JohnnyMalaria on February 22, 2021, 02:50:31 pmSimilarly, decades ago when I started using SMD parts (beginning with 1206), we found it easy to put two components in parallel by soldering one above the other, when circumstances required (probably no longer allowed, especially with smaller parts).

author: Zero999
author_rank: Super Contributor
timestamp: February 22, 2021, 06:32:07 pm
content: 320k being a E192 preferred number, will be more expensive because fewer will be made and it will be a precision part, with a tolerance of 0.5%, or better.I still don't see the reason for the values listed? Obviously they're powers of two, but I would go for 7k5, 15k, 30k, 60k (two: 30k in series, or 120k in parallel), 120k and 240k. It would be much easier to use an R-2R ladder instead.https://en.wikipedia.org/wiki/Resistor_ladder

author: David Hess
author_rank: Super Contributor
timestamp: February 22, 2021, 06:48:29 pm
content: Quote from: Jan Audio on February 19, 2021, 03:50:18 pmI usually end up using some values in series and parallel to reduce the number of separate value needed. Or use a R-R2 DAC configuration instead which only requires two values:https://en.wikipedia.org/wiki/Resistor_ladder#R%E2%80%932R_resistor_ladder_network_(digital_to_analog_conversion)

author: Bassman59
author_rank: Super Contributor
timestamp: February 22, 2021, 07:17:42 pm
content: Quote from: bdunham7 on February 22, 2021, 03:06:07 pmYou say that like it's a bad thing!

author: ogden
author_rank: Super Contributor
timestamp: February 22, 2021, 11:18:10 pm
content: Quote from: Jan Audio on February 22, 2021, 03:26:23 pmProper question shall be - why sane engineer would use such resistors in 6-bit ADC?

author: tooki
author_rank: Super Contributor
timestamp: February 22, 2021, 11:27:16 pm
content: Quote from: Jan Audio on February 20, 2021, 04:04:25 pmWith parts that have no substitutes, sure. But ordinary resistors? No way. A high-volume manufacturer that needs an unusual value will just order them (or even custom values), since they need lots anyway. And for small volume projects and repairs, you just use combinations of common values.

author: Vovk_Z
author_rank: Super Contributor
timestamp: February 22, 2021, 11:42:44 pm
content: Quote from: Jan Audio on February 22, 2021, 02:29:45 pmI usually use TH parts (resistors) only when prototyping. Almost totally moved to SMD. There are few places where we really have to use TH parts.

author: retiredfeline
author_rank: Frequent Contributor
timestamp: February 23, 2021, 12:03:21 am
content: Should be half enough for everybody.

author: TimFox
author_rank: Super Contributor
timestamp: February 23, 2021, 12:03:52 am
content: Quote from: tooki on February 22, 2021, 11:27:16 pmDigiKey shows several pages of 320 kTH resistors, but none of them is stocked. If you have need of a sufficient minimum order quantity, they will supply you. If it were me, I would use two resistors in series.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 23, 2021, 03:14:26 pm
content: Thanks all.Why i use such a DAC ?, it works, i am just happy with stuff that works.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 23, 2021, 03:23:48 pm
content: This DAC reacts instantly, while a SPI DAC is slower.It uses a few parts, the other DAC has more resistors.

author: MK14
author_rank: Super Contributor
timestamp: February 23, 2021, 03:51:07 pm
content: Requirements apparently met:Through Hole1% ToleranceIn Stock - Almost 700,000Less than $0.05 each. These are around $0.035, for x1000, less for bigger quantities320K0.5 WattsMetal FilmBy Vishay CMF55320K00FHBFhttps://www.component-en.com/products/CMF55320K00FHBF/13919735Disclaimer:I have no idea on the quality of that supplier, so check them out yourself, please.

author: tooki
author_rank: Super Contributor
timestamp: February 26, 2021, 05:07:37 am
content: Quote from: TimFox on February 23, 2021, 12:03:52 amI know that. You simply rephrased my reply, which was in response to OP’s claim of there being lots of money to be made in stockpiling “obsolete” resistors. I was explaining why that’s silly, since volume customers can get them if they need them (and wouldn’t buy them from some random guy anyway), and small customers would just design around the problem by using combinations. There’s no significant clientele for old stockpiled resistors.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 26, 2021, 02:19:20 pm
content: Quote from: JohnnyMalaria on February 22, 2021, 02:50:31 pmIt seems very hard to make a 320K resistor like this.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 26, 2021, 02:24:02 pm
content: Quote from: tooki on February 26, 2021, 05:07:37 amI say with any parts not resistors.If you have any type of THT transistor FET etc or opamp or anything becoming obsolete, not resistors.You can still stockpile them dont worry, and you could make lots of money does not means you gonna make 100% sure alot of money.

author: drussell
author_rank: Super Contributor
timestamp: February 26, 2021, 02:29:36 pm
content: Quote from: Jan Audio on February 26, 2021, 02:19:20 pmReally? Two 160k1/8W resistors end to end in series isn't difficult.1. Twist the leads between the two closely together over a short distance, solder them together and trim the excess lead length, essentially making one1/4W resistor.2. Insert into PCB and pretend it is one resistor.You can simply "tent" the joined resistors up a bit if you've made the part too long to fit directly between existing holes. Job done.Unless you have very limited space above the PCB this is not a problem. You can even join the two side-by-side, one going up and one going down to the PCB instead of soldering them end to end. Resistors are often mounted vertically to save space, there is nothing inherently wrong with standing up a resistor, it's not like they know what orientation they're in.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 26, 2021, 02:31:51 pm
content: Quote from: drussell on February 26, 2021, 02:29:36 pmI like to see that in the picture.

author: Monkeh
author_rank: Super Contributor
timestamp: February 26, 2021, 02:33:41 pm
content: Quote from: Jan Audio on February 26, 2021, 02:31:51 pmWhy not just do it yourself? You could be long finished by now making your two boards.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 26, 2021, 02:34:17 pm
content: Please no more reactions.

author: AndyC_772
author_rank: Super Contributor
timestamp: February 26, 2021, 02:35:45 pm
content: 470k // 1M = 319.728k, which is an error of -0.085%.Also try 365k // 2.61M = 320.218k, or 332k // 8.87M = 320.022k.Recommended app: Electrodoc Pro - it has all kinds of useful tools for electronics.

author: drussell
author_rank: Super Contributor
timestamp: February 26, 2021, 03:22:29 pm
content: Quote from: Jan Audio on February 26, 2021, 02:31:51 pmI'm not sure why you can't picture this in your mind's eye, but okay then...Here are two random 680K resistors from in front of me, turned into a 1.36 meg:You can even just twist them together, solder them into the board,thensolder the joint between them and trim the leads. Easy peasy.Quote from: Monkeh on February 26, 2021, 02:33:41 pmIndeed.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 26, 2021, 03:33:16 pm
content: Quote from: Monkeh on February 26, 2021, 02:33:41 pmWhat boards ?, i dont make anything with this,i just have some tricks in my trickbox.

author: Monkeh
author_rank: Super Contributor
timestamp: February 26, 2021, 05:42:07 pm
content: Quote from: Jan Audio on February 26, 2021, 03:33:16 pmSo let me get this straight, you're complaining about the expense of buying parts you shouldn't have chosen and don't need?

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: February 26, 2021, 05:48:37 pm
content: Quote from: drussell on February 26, 2021, 03:22:29 pmOT - not everyone has a mind's eye, including me. It's called aphantasia. It wasn't until I was about 50 that I learned that most people really can create images in their heads. Blew my mind. I can't explain it but, taking the example of the two resistors, I can conceive it in my mind and know what it's all about but I don't visualize anything. (But I can see in perfect 3D with one eye...)

author: drussell
author_rank: Super Contributor
timestamp: February 26, 2021, 06:15:00 pm
content: Quote from: Monkeh on February 26, 2021, 05:42:07 pmYeah... Yup... Pretty much...For some unknown reason, instead of just ignoring this thread from the get-go, I've been watching with

author: drussell
author_rank: Super Contributor
timestamp: February 26, 2021, 07:04:43 pm
content: Quote from: JohnnyMalaria on February 26, 2021, 05:48:37 pmI realize that someone might not be able to fully "visualize" a concept, especially one that is outside what they have really ever considered before, which is why I have no problem posting a picture of what I'm talking about. I just didn't expect that the idea of putting two resistors physically in series would be any sort of an abstract concept. There are many physical forms to easily achieve the desired result.(As to the sanity of stressing over the absolutely precise, <1% accuracy of a poorly chosen component value in this specific type of circuit, I am less sure. Why something like a 316 or 324 or somesuch value wouldn't be considered completely adequate and appropriate in a 6-bit DAC circuit, let alone choosing more sane values in the first place, I have no idea.)

author: drussell
author_rank: Super Contributor
timestamp: February 26, 2021, 07:30:23 pm
content: Quote from: Jan Audio on February 26, 2021, 02:19:20 pmQuote from: AndyC_772 on February 26, 2021, 02:35:45 pmIndeed.I'm not sure why the OP is so obsessed with such tight tolerance of this particular value, but even a paralleled set of commonly available 560K and 750K values getsmorethan close enough for any reason whichIcan conceive of.

author: drussell
author_rank: Super Contributor
timestamp: February 26, 2021, 08:49:33 pm
content: Quote from: ebastler on February 26, 2021, 08:23:33 pmAs long as you get 1% or better spec'd resistors you could obviously use a bunch of different combinations, and sure, many common values are available in even tighter tolerance versions which you can use for getting unnecessarily close to some particular value if you wish. I still don't think the OP is actually trying to create a .01% accurate 6-bit DAC, even though they seem to think they are.Usually when precise matching is required, binned testing of incoming lower-tolerance yet stable components would be sorted into matched pairs/quads or whatever and then specifically indicated as selected components on the schematics and BOM.It still seems silly that the OP is "needing" something so precise in the first place, given the tolerance of typical components used in such situations, but...

author: Jan Audio
author_rank: Frequent Contributor
timestamp: February 27, 2021, 02:30:35 pm
content: Quote from: Monkeh on February 26, 2021, 05:42:07 pmYes.

author: Zero999
author_rank: Super Contributor
timestamp: February 28, 2021, 06:25:18 pm
content: Quote from: Jan Audio on February 27, 2021, 02:30:35 pmQuote from: Jan Audio on February 26, 2021, 02:34:17 pmWhy ask then?There are plenty of resistor combinations to give 320k. Use the calculator linked below, to work it out for you.http://jansson.us/resistors.html

author: coppercone2
author_rank: Super Contributor
timestamp: February 28, 2021, 07:32:09 pm
content: you know maybe he is trying to sell this thing and someone just does not want a bodge in a finished systemit looks bad. its like sending something with a crooked decal.just buy this,https://www.mouser.com/ProductDetail/Vishay-Dale/RN55C3203BB14/?qs=sGAEpiMZZMsPqMdJzcrNwvkdYAxQ3%2Fr%2Fs3q5pENnkCQ%3Dand end this thread. its like watching a beat down in slow motionglue it in an copper tube to increase dissipation to make a really small heat sink if you must, just end this thread, its painful at this pointi would say even make a custom heat sink for a small axial resistor, just stop this war.https://www.ebay.com/itm/Lot-of-Vishay-Dale-320K-Ohm-1-2-Watt-1-Metal-Film-Resistors/203140201001?hash=item2f4c197a29:g:lj0AAOSwy0tfh0lrthis thread is pure bias, i feel like im watching the goverment try to enforce a modernization policy in a soviet countryi recall there being like a 500 page thread about equipment knobs (you can get by using a dowel) but a resistor is turns into ww3

author: tooki
author_rank: Super Contributor
timestamp: February 28, 2021, 07:42:04 pm
content: Quote from: coppercone2 on February 28, 2021, 07:32:09 pmBut the OP already said they don’t actually have an application for it, it’s purely hypothetical.

author: coppercone2
author_rank: Super Contributor
timestamp: February 28, 2021, 08:35:42 pm
content: i think its a custom design for sale to someone that likes audio

author: Monkeh
author_rank: Super Contributor
timestamp: February 28, 2021, 08:37:57 pm
content: Quote from: coppercone2 on February 28, 2021, 08:35:42 pmI think you're reaching to justify your indignation.

author: Jan Audio
author_rank: Frequent Contributor
timestamp: March 01, 2021, 03:53:06 pm
content: Quote from: coppercone2 on February 28, 2021, 07:32:09 pmAmerikan style, no listening, just harder screaming.Dont wanto start ww3 for a resistor.Remember this is in general technical chat, not beginners or projects, dont force me any more help please.

author: TimFox
author_rank: Super Contributor
timestamp: March 01, 2021, 04:14:57 pm
content: Actually, the majority of recent replies that seem to mock you, as opposed to those who suggest possible solutions to your original problem, are from non-American members.In the US, the spelling "Amerikan" is used in political circles to suggest bad things about other writers.

author: JohnnyMalaria
author_rank: Super Contributor
timestamp: March 01, 2021, 04:17:33 pm
content: Quote from: Jan Audio on March 01, 2021, 03:53:06 pmYou can stop this thread showing up...

author: Jan Audio
author_rank: Frequent Contributor
timestamp: March 01, 2021, 04:32:08 pm
content: Quote from: TimFox on March 01, 2021, 04:14:57 pmOk learning everyday.America = Amerika in dutch.Dont wanto be racist, i better remove the political statement its not allowed.

author: DrG
author_rank: Super Contributor
timestamp: March 01, 2021, 05:11:31 pm
content: Quote from: Jan Audio on March 01, 2021, 03:53:06 pmMaybe you could get a job un-ringing bells and they could pay you in 320K resistors?

author: Jan Audio
author_rank: Frequent Contributor
timestamp: March 01, 2021, 05:22:19 pm
content: Hey i did not start about your government, your fellow amerikan did.

author: Terry Bites
author_rank: Super Contributor
timestamp: March 02, 2021, 01:36:18 pm
content: Two 160k in series is 320k. Strange yet true....

author: mariush
author_rank: Super Contributor
timestamp: March 02, 2021, 04:28:21 pm
content: If you're concerned about looks., you could just have footprints for two resistors in series for each resistor. Then, use 0 ohm resistors where a resistor is not needed.If you use surface mount resistors, 0603 or 0402 resistors don't take that much space.Surface mount resistors would also allow you to stack two resistors, one on top of the other... basically two resistors in parallel.

author: Monkeh
author_rank: Super Contributor
timestamp: March 02, 2021, 04:39:06 pm
content: Quote from: mariush on March 02, 2021, 04:28:21 pmBut.. SMD is for pros. He's only a hobbyist, he can't handle that.

author: Chris56000
author_rank: Frequent Contributor
timestamp: August 08, 2021, 06:06:58 am
content: Hi!If I was making this thing the OP wants the 320k resistor is for, I would start with 1.0 and 1.6 in series or parallel combinations and their decades ! Job done !What I did want to say is, what about old pieces of T & M that use component values even E192 doesn't come near?!Where would I find 9.9nF and 932pF polystyrene capacitors, as used in some old Cossor Oscilloscopes, without making an unsightly mess around the timebase speed switch using combinations of whatever can be obtained, for example?The only way to get these is a "parts mule", and there are a few cases on record of these capacitors failing short–circuit due to "silver migration".The only answer to this one would be to redesign the components around the timebase speed switch to use what capacitors are available, possibly with E192 resistors !Chris Williams

author: ebastler
author_rank: Super Contributor
timestamp: August 08, 2021, 08:35:36 am
content: Quote from: Chris56000 on August 08, 2021, 06:06:58 amWhat are the tolerances of those parts, and how critical is the value in the scope?E.g. I did find 932 pF capacitors here (http://www.amidon.de/contents/de/d668_01.html), but their specified tolerance is 5%. That would mean that a 910 pF capacitor (E24) should work nicely, provided you find (select) one which is not in the lower half of its own tolerance range. Ditto for the 9.9 nF: Would 10 nF not work?

author: Zero999
author_rank: Super Contributor
timestamp: August 08, 2021, 11:59:01 am
content: Quote from: Monkeh on March 02, 2021, 04:39:06 pmNonsense. The larger SMT parts are easy to use, especially 805 and 1206 parts which can fit between two tracks on some stripboard.Quote from: ebastler on August 08, 2021, 08:35:36 am18nF & 22nF in series.

author: Monkeh
author_rank: Super Contributor
timestamp: August 08, 2021, 04:48:37 pm
content: Quote from: Zero999 on August 08, 2021, 11:59:01 amYou might want to read the whole thread for some context.

author: Zero999
author_rank: Super Contributor
timestamp: August 08, 2021, 05:23:29 pm
content: Quote from: Monkeh on August 08, 2021, 04:48:37 pmI can't be bothered to re-read this old thread, but I was using SMD parts, when I was 12. You'd have to be petty bad at soldering, to not be able to use them.

author: ebastler
author_rank: Super Contributor
timestamp: August 08, 2021, 05:48:47 pm
content: Quote from: Zero999 on August 08, 2021, 05:23:29 pmThen you should at least bother to fix your irony detector.