hybridfree/eevblog-posts huggingface dataset:
Solar Pond Pump Battery Backup - Page 1
Forum section: electronics / beginners

author: MrWizerd
author_rank: Contributor
timestamp: September 27, 2015, 10:36:44 pm
content: I am putting this here because I am sure this is a total noob question but...I bought a cheap solar powered pond pump and I want to set it up to be able to run while the sun is shining, and charge a battery when the sun is shining, but when the sun is gone for the battery to power the pump. I have two small solar panels, both are able to operate the little pond pump. One is rated at 170mA with a measured 8.5v on a cloudy day, the other I have measured at 40mA at 7v on a cloudy day. The bigger one runs the pump well, the pump operates at 5-12v and 100-250mA/h. My thought was to use a 9v rechargeable battery and either charge it with the smaller panel or setup the two panels in series and charge while running the pump, and then run the pump when the sun goes down from that same 9v. I don't know if I can get a significant charge in either situation and I may need to switch to bigger panels to do this. I have thought of a couple ways to go about doing this, but I am not sure which would be the best way to accomplish something like this. Anyone have thoughts?
Solar powered fan circuit - please help!  - Page 1
Forum section: electronics / beginners

author: nuttam
author_rank: Newbie
timestamp: May 27, 2017, 10:32:08 am
content: I'm totally new to working with electronics, and have no idea how to achieve what I need. I'm hoping someone here can help.I'm looking to provide mechanical ventilation to my shed. It's only a shed, and so cost is very much an issue.Given its position, my best bet is to solar power a small fan.I'm looking at a small panel (Maximum power voltage: 17.9V, Maximum power current: 0.28A, Open circuit voltage: 22.4V, Short circuit current: 0.3A, Power allowance range: +/-3%) and something like a PC case fan (12v, approx. 4w - open to suggestions).From my limited understanding, if I wire the panel straight to the fan it'll burn out (or the shed will take off like a helicopter).Any help on how to make this work would be really appreciated.Many thanks, Mark

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: May 27, 2017, 11:21:59 am
content: rated current for fan = 4W/12v = 0.3 ampswhich is uncannily close to your solar panels max output. I'm sure it will be fine.

author: Seekonk
author_rank: Super Contributor
timestamp: May 27, 2017, 01:10:26 pm
content: Agree. If you had a bigger panel, there is a way to convert a cheap ebay buck converter into a Linear Current Booster. Actually, it would also help in this under power situation. Even though it only takes about 5 parts, it might be above your skill level. I've been suggesting it for years and no one to my knowledge has ever used it.

author: Zero999
author_rank: Super Contributor
timestamp: May 27, 2017, 01:26:30 pm
content: The voltage across the solar panel will drop when the fan is connected. The trouble is, when the sun is shining brightly it might not fall below the fan's absolute maximum operating voltage.To test this, you could use a constant current sink to draw whatever current the fan draws from the solar panel and measure the voltage.If the voltage of the solar panels is too high, you could connect the fan via a low drop-out regulator or add a shunt regulator, such as a 12V zener diode or the TL431 + a few resistors and transistor mounted on a heat sink.
Solar PV MPPT with Constant Power / Power Limit Output Where to Get? - Page 1
Forum section: electronics / beginners

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 09, 2022, 05:36:56 pm
content: i'm venturing into solar power for a small boat with motor... so i bought 2x 100W PV and a $5 Hung Low Charger Controller, it claims as MPPT but looking at the circuit teardown, it should be simple PWM based controller, but so far so good, a lot better than connecting a motor (12V 5A) directly to the PV, the little problem is when prolonged usage, its like throttling the power, not sure how it does that... it doesnt have temperature sensor from the look of it. but thats not the point (we cant expect to much from $5)...the big deal is actually when its become cloudy and PV cannot fully supply 5A to the motor, so i measured the current is drawn from the battery and slowly depleted. what i really want is i can set to power limit mode (reduce output voltage), ie i dont want power comes from the battery during the day because i want to save the battery power during the night or emergency situation in the middle of the sea. i dont mind if the motor becomes slower operated at lower output voltage, at least i can still move slowly during the day. in case i want to move faster at full motor rating, i can push a button for normal 12V output mode, ie power comes from both PV and battery. is there any such MPPT charger controller like that? at affordable price if possible (10-30A spec 100-200W, for 24-30Voc PV) so i dont have to reinvent the wheel... i tried google no luck, maybe wrong keyword.. cheers.

author: Mechatrommer
author_rank: Super Contributor
timestamp: January 19, 2022, 06:00:21 pm
content: looks like i have to invent a "new" type of wheel
Solar roof ventilation fan - Add lithium battery? - Page 1
Forum section: electronics / beginners

author: darrenjc
author_rank: Newbie
timestamp: December 21, 2019, 03:26:09 am
content: Hi,I have a basic roof ventilation fan with a 12v solar panel built in. (Bunnings Ezylite 200mm Solar Roof Vent Fan)It works great but I don't want it to stop when the sun goes down, so I was thinking of adding a 12v battery in parallel to keep the voltage up and spin the fan...However, I know it's not that simple.Issues -Overcharge - I'm sure the battery would try to overcharge and id need way to limit current when it's charged.Current - I can measure the current demands during the day to see how much it draws, then spec the battery to last overnight.Do I need a charge controller?Can I just build a simple charging circuit?Will the solar panel have enough power to run the fan as the priority, but also trickle charge the battery durign the day?12v solar12v motorCurrent - Probably only 300mA?Thanks in advance
Solder "Min junction temp" ? - Page 1
Forum section: electronics / beginners

author: peps1
author_rank: Regular Contributor
timestamp: September 22, 2017, 05:48:24 pm
content: Hey guys, planing on testing out some dip soldering and have just got my solder in, so checked the data sheet for the melting point, and I see a higher temp called Minimum junction temp, what is the "Min junction temp"?Google search seems to just come up with a lot of PDF's mainly about BJTs and MOFETSits the 60/40Pellets on this datasheet attached.

author: ConKbot
author_rank: Super Contributor
timestamp: September 22, 2017, 06:08:44 pm
content: I'd guess it's the temperature they want you to get the junction of the things you're soldering upto. When when you solder, you're forming intermetallic compounds, (I.e. a tin-copper, and lead-copper compound) at the interface between the two, so just melting the solder isn't enough, it has to be able to form the IMC layer to an appropriate thicknesses as it wets the surfaces.Heating copperclad on a hot plate with solder paste on it, I've seen the solder bead up momentarily before wetting the copper. I figured the flux needed time to make stuff happen, but it could have been the fact that IMCs hadn't formed because the temperature was too low.Hopefully someone with real metallurgy experience can give some insight.
Solder and Desoldering wick sizes for smd? - Page 1
Forum section: electronics / beginners

author: jamesmith134
author_rank: Newbie
timestamp: March 24, 2014, 10:35:00 am
content: Hello!What sizes of solder and desoldering wick should I choose for smd rework?*Edit : Also, what is your preference ? 63/37 or 60/40?Thanks!

author: nanofrog
author_rank: Super Contributor
timestamp: March 24, 2014, 05:20:27 pm
content: You want to match the size of the pad to the size of the wick (.pdf sizing guide<other useful tidbits of info in this>), so it will depend on what packages you're trying to solder.Based on passive packages (resistors/capacitors), the following might be of some use.#1/White; 0402 & smaller#2/Yellow; 0805 & 0603#3/Green; 1206#4/Blue; 1210#5/Brown; 2512 & 2010#6/Red; 1218Chemtronics also makes a Purple size, which is meant for BGA.#3, #4, #5 are also quite useful sizes for thru-hole pads.At home, I compromise a bit to skip keeping every single size on hand, so I only keep a few sizes (#2 - 5, and use #2 & 3 the most).For solder size, I use .025" wire diameter 63/37 primarily (.020' is also liked by many). If you do a lot of thru-hole, .031" is a bit more useful IMHO as it doesn't take quite as long a piece so the solder time is shorter (less to feed into the joint, so you get the heat off faster). You can also wrap a couple to three loops around your fingers of the finer diameter, then twist for larger joints (tinning thicker wire & thru-hole for example). Do note that the smaller diameter wire sizes will cost more, all other things equal.Get good quality supplies rather than eBay specials. Works vs. lots of frustration and possibly damage. Chemtronics is top notch for wick (figure good stuff is ~$4 per 5' bobbin), and Kester will be readily available to you for solder here in the US (under $30 for a 1lb spool if you look; All-Spec and Stanley Supply would be places to look for some good deals). I prefer rosin, but will also use no-clean.I'd recommend staying away from water soluble fluxes, as they have to be cleaned off within a few hours of soldering, or it will corrode your freshly made joints and the PCB pads.
Solder BMS to 7 cell - Page 1
Forum section: electronics / beginners

author: imjust_ajoke
author_rank: Newbie
timestamp: June 09, 2018, 09:52:21 am
content: Hi all,First of all thanks for viewing my thread I have a quick question recently I brought a BMS for my 7 cell 18650 battery..I can't find the diagram online to solder the bms..Hope anyone with the knowledge could help me outI have attached the BMSThanksSent from my SM-N950F using Tapatalk

author: viperidae
author_rank: Frequent Contributor
timestamp: June 09, 2018, 09:12:53 pm
content: Is there a particular reason why you put all the cells the same direction and used long wires to connect them?Alternating the direction let's you use short wires.

author: sleemanj
author_rank: Super Contributor
timestamp: June 09, 2018, 09:50:27 pm
content: Balance: Black = most negative, Red = most positive, and the whites in the middle are each middle node in the obvious sequence.Power: The large B- tab goes to most negative, P- is where you draw current from, and C- is the negative connection point for your charger. If there is no B+/P+/C+ pass through (maybe on the back side) then just connect your load/charger directly to the battery +

author: imjust_ajoke
author_rank: Newbie
timestamp: June 10, 2018, 01:35:12 am
content: Quote from: viperidae on June 09, 2018, 09:12:53 pmActually no...Sent from my SM-N950F using Tapatalk

author: imjust_ajoke
author_rank: Newbie
timestamp: June 10, 2018, 01:36:24 am
content: Quote from: sleemanj on June 09, 2018, 09:50:27 pmThanks...As I google along I found this image which I'm more confuse nowSent from my SM-N950F using Tapatalk
Solder fume filter? - Page 1
Forum section: electronics / beginners

author: geratheg
author_rank: Regular Contributor
timestamp: July 26, 2014, 06:00:44 am
content: I'm planning on building a fume extractor using a 120mm PC fan.Still thinking about which filter to get.I was told carbon filters are used for this.What is the MERV rating needed for a solder fume filter?Where do you get your filters?Is this a good filter or at least good enough for hobby use? (MERV 6)http://www.mcmaster.com/#catalog/120/688/=t00igwItem number: 3722T48

author: made2hack
author_rank: Frequent Contributor
timestamp: July 26, 2014, 08:31:55 pm
content: In the Mcmaster link you sent, use the "Odor Removal" type as that has activated carbon in it, and it is what you want to trap the fumes.Also, aquarium activated carbon also works, if the granules are small enough. Or there is activated carbon pieces for external and internal water filters that work.Heck, you can use wood charcoal if you feel like grinding it yourself.As for MERV, don't know. According to wikipedia, MERV of 6 falls into the "Mold, spores, dust mite debris, cat and dog dander, hair spray, fabric protector, dusting aids, pudding mix" part.Minium Efficiency Reporting ValuesThe fact that you are already sucking the fumes away through activated carbon, I don't think you need to worry too much about the MERV, especially if the filter you use isn't very porous. Most activated carbon does a VERY GOOD job removing fumes, chemicals, smells, you name it, it can handle it.

author: made2hack
author_rank: Frequent Contributor
timestamp: July 26, 2014, 08:33:35 pm
content: Forgot to mention. Whatever activated carbon filter you do end up using, just remember to replace it every 6 months.If you do high volume soldering, and the pad filter isn't too large (as would be with a 120mm diameter filter), maybe replace every 3-4 months the filter.
Solder Mask Question Need Help. - Page 1
Forum section: electronics / beginners

author: wade7575
author_rank: Contributor
timestamp: September 19, 2019, 05:52:55 am
content: I need to get some Solder Mask and I was wondering about the UV Curable stuff and how it works.I need to refresh some special sharpening stones that use a Copper Tin matrix that hold CBN in place and you use Ferric Chloride to remove some of the Copper Tin.If you look at the picture I attached to this post you can see the stone is mounted to an aluminum blank and it has laser engraving on it to tell you the grit and I want to protect the blank.What I was wondering is if the solder mask in the link will stop the Ferric Chloride from harming the aluminum blank,I don't care blank the edge's of the blank if the get muddy looking.This is the Solder Mask I was looking at getting in the link below,I know about the MG stuff but for the amount I need it's to much money.What's the best way to clean this stuff off.https://www.amazon.ca/Solder-Stencil-Flashlight-Paint-Shedding-Storage/dp/B07JFNZYHQ/ref=sr_1_6?keywords=solder%2Bmask&qid=1568869172&s=industrial&sr=1-6&th=1

author: sleemanj
author_rank: Super Contributor
timestamp: September 19, 2019, 06:45:51 am
content: Soldermask won't be coming off in a hurry without application of an angle grinder, the point is it is largely impervious to damage after all. Any chemical to strip the soldermask is also going to damage the aluminium I expect. I don't think that is what you want.You could maybe use a spray on etch resist, maybe. Or maybe some latex type sealant or paintable silicone (casting silicone) you could peel off.Best way is to remove the stone from the plinth.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: September 19, 2019, 07:02:42 am
content: Why not use nitric acid? Won't attack the aluminum.Heh... why indeed, right? Can get it from chemical suppliers, but if you don't meet their checks, it kinda sucks. Well, you can make it in-situ with sulfuric acid (drain cleaner?) and a nitrate salt. Sulfuric won't attack aluminum either, at least not very quickly, but an oxidizer is needed to attack copper.Also, tin? What form of tin? Isn't tin a mask against ferric chloride?What's wrong with conventional masks like... just regular old grease or paint or tape?Soldermask is rather tenacious as mentioned above, but a chemical stripper (preferably methylene chloride based?) will remove it without affecting the metals.I suppose even just good old fashioned heat might work, too. Unless there's an organic adhesive bond layer in there already. The supposition is whether anything adverse results (CBN should be stable at red heat, I think? Aluminum will be annealed though, and may be too soft.)Tim

author: wade7575
author_rank: Contributor
timestamp: September 19, 2019, 07:12:41 am
content: CBN is synthetic diamond but made a bit different but still the the same,CBN when you used on grinding stand up to more heat then natural diamonds,diamonds will get soft and break down at a lower temp then CBN will.What about the MG Solder mask.
Solder mask question - Page 1
Forum section: electronics / beginners

author: Dave Wave
author_rank: Contributor
timestamp: July 30, 2013, 11:33:48 am
content: So I got an xbox that had rrod.I got a kit that change the heatsink mounting and fixed the problem.The kit uses metal washers between the heatsink and the PCB.The washers are slightly larger in dia than the pad around the hole on the pcb and comes very close to/covers a trace on the pcb.I would assume that there is a solder mask covering the trace, preventing it from shorting out to the grounded heatsink.How durable is the mask? Is this going to short out at some point do to the pressure of the washer?Anybody care to chime in?Thanks!-Dave

author: digsys
author_rank: Unknown
timestamp: July 30, 2013, 11:38:11 am
content: With pressure and heat, there's a very good chance the washer will eventually "sink" through the mask,after all, it was only a liquid when first applied. Definitely worth fixing !!
Solder pad dimensions - Page 1
Forum section: electronics / beginners

author: anotherlin
author_rank: Frequent Contributor
timestamp: June 05, 2020, 10:02:59 pm
content: Hi everyone,Is there an electronical rule or just a rule of thumb regarding solder pad dimensions?That is, if I have a 0.025 inch diameter drill hole (suitable for 24AWG wire), what should the total diameter of the solder pad?This is to have an appropriate surface of pad to solder on for both good electrical and mechanical properties.What ratio should I use? x2, x3? Which would give a total diameter of 0.05 and 0.075 inches respectively.If I want to have the same surface between the drilled hole and the soldering pad, I should take a sqrt(2) ratio.But that looks (at least visually) a very small surface.Any suggestion, or even pointer to material for good PCB design practices?Thank you.Best regards,
Solder pad repair - Page 1
Forum section: electronics / beginners

author: Cj1
author_rank: Contributor
timestamp: October 24, 2017, 04:15:25 am
content: I was given a broken video game console by a friend to practice my soldering on. I noticed one of the pads is lifted but still attached to the trace. I have never repaired a lifted component before so im not sure how to proceed.The pad thats lifted looks the its the end of the line so to speak, so im wondering if i can just leave it as is since its still attached to the trace. I was thinking of trying to reattach it to the board. Do i just scrape away the resin on the pad to expose the copper? I don't think it was attached to any other components...My camera isn't the best but here are some pictures:https://imgur.com/a/EJett

author: frog
author_rank: Contributor
timestamp: October 24, 2017, 04:31:42 am
content: So long as the electrical connections are made, it should still work even if the track has lifted from the board. However the component it's attached to will not be properly anchored and so I wouldn't bet on its life expectancy, especially if it's subject to movement/handling. If your repair is successful and you want to reinforce it, try hot glue or epoxy resin *once you've confirmed that it's working*. Good luck

author: macboy
author_rank: Super Contributor
timestamp: October 24, 2017, 02:01:21 pm
content: hot glue?Just ... no.Use epoxy to glue the trace back down flat to the board. PCBs are made of epoxy and fiberglass (common FR4 is anyway). It is strong and heat resistant. Epoxy won't stick to kitchen "parchment paper" or "baking paper", so put some of that over the repair area and clamp it down with something flat while the epoxy cures. Give it 24 hours, at room temperature, even for so-called 5 minute stuff. Drill out the hole since it will have filled with epoxy. You can gently scrape the top of the repaired pad with the flat edge (not corner!) of a flat screwdriver to remove any little bit of epoxy covering the trace. Then solder as normal.Don't be tempted to use super glue (Cyanoacrylate glue). It will soften too much when heated to soldering temperature and will give off nasty noxious fumes.
Solder paste (a bit of noob, maybe some science) - Page 1
Forum section: electronics / beginners

author: MyHeadHz
author_rank: Regular Contributor
timestamp: December 18, 2019, 11:31:12 pm
content: I was considering branching out from through-hole components into SMD. The sticking point for me is the shelf life of solder paste, because it would mean needing a 1 week lead time and $15 of solder paste overhead before every session. So I researched a bit in the archives here.Thereseemto be some disagreements among the members here. There are 3 basic groups of ideas that make it unusable: 1. evaporation makes it dry out. 2. the metal powder/micro-balls settle out of the flux. 3. Some necessary solvent evaporates and renders it useless, or the hygroscopic flux won't work with too much water (water displacement).(It is also worth noting that everyone seems to agree that there is no chemistry changes going on.)So it's still not so clear. However, some of these three causes might have viable solutions for the home gamer.There has beeninvolving ultrasonic cleaners that might be able to re-suspend these particles, or re-constitute dried out paste. Perhaps a similar process could work if the solvent has been displaced by water, but with a drying phase first.Ultimately, the goal would be to have a simple process of preparing/preserving old solder paste for use whenever, to save cost and time. That, and I'm trying to find an excuse to buy an ultrasonic cleaner after watching that video.Think any of this is plausible, or is it a dead end?

author: GerryR
author_rank: Frequent Contributor
timestamp: December 19, 2019, 12:16:07 am
content: Well, just go ahead and get the Ultrasonic Cleaner,I keep my solder paste in the refrigerator, which prolongs its life.

author: JustMeHere
author_rank: Frequent Contributor
timestamp: December 19, 2019, 02:19:02 am
content: My 3+ year old solder paste tube still works well enough. For low scale production, I wouldn't worry about it.

author: pmercier
author_rank: Contributor
timestamp: December 19, 2019, 09:30:32 am
content: I've some chineese solder paste that aged for 3 year now on my bench at normal temperature with no particular care about storage (bad bad bad boy).It's still usable but a little too "pasty". When i need some i just take some and mix it with little isopropyl alcool and use it quickly. Perhaps not the best thing to do, but ... it work for me.
solder paste not "sticking" to pcb - Page 1
Forum section: electronics / beginners

author: Simon
author_rank: Unknown
timestamp: May 06, 2014, 01:43:56 pm
content: Well i bought a tube of solder paste and eventually some bog bloges later had a soldered board. Bit what I did find was that the paste did not exactly want to stick to me PCB it was a job to "leave some behind" on the pads. Should I have put flux on the board first ?

author: Codemonkey
author_rank: Regular Contributor
timestamp: May 06, 2014, 02:03:49 pm
content: Had you just taken it out of the fridge ? If its a bit cold its not so easy to work with. To be honest, I avoid using it unless I have a paste mask to screen print it on with, I find normal solder easier to work with. I imagine adding more flux will result in it just spreading out all over the board once deposited.

author: Simon
author_rank: Unknown
timestamp: May 06, 2014, 02:28:57 pm
content: it had been out a little while but then I have no idea how ling it takes a lump of solder like that to come to temperature, I suppose the plastic syringe acts as a thermal insulator.

author: geo_leeman
author_rank: Regular Contributor
timestamp: May 06, 2014, 03:17:29 pm
content: Seems that at mine works pretty decent after about an hour out at room temperature.

author: MacAttak
author_rank: Unknown
timestamp: May 07, 2014, 12:35:39 am
content: The good thing is that you don't need to get the paste perfectly on the pads when dabbing it on from the syringe. When it reflows it will push away from the soldermasked areas and pool on the pads naturally (exactly where you want it).I've done a few chips where the pin pitch was to small to cleanly apply paste, or where device disassembly was such a PITA that I chose to solder the board while it was still installed (making it very hard to get close to the board while applying solder). In those cases, I just cleaned the pads and mask well with IPA and then dragged a thin line of paste across the line of pads. Reflowed with hot air and the solder pools itself to the right places and pulls the chip right into place.

author: Simon
author_rank: Unknown
timestamp: May 07, 2014, 09:43:27 am
content: in fact on my first board you could not see the solder mask for the solder but it all went where it was supposed to like you say. Although some parts did not solder quite straight die to the sheer quantity of solder.
Solder paste recommendations. - Page 1
Forum section: electronics / beginners

author: jgalak
author_rank: Regular Contributor
timestamp: December 07, 2017, 02:50:51 pm
content: I'm going to try my first reflow project, and looking for advice on solder paste. Small board, just a few parts (QFN20, 0402, and a weird custom one, but larger pitch than those). Stainless stencil. Going to use a hot air station since I don't have an oven yet. Strictly hobby use.So. Leaded or lead-free? I'm not super concerned about lead, since I don't think it's a health hazard in hobbyist levels. Of course less is better, but for hand soldering I use 63/37 or 60/40, they just work better. As this is my first attempt, would leaded be easier?Particular brands? The stencil manufacturer is offering Kester NXG1 (lead free) or Kester EP256 (leaded), are these any good? Other specific brands you'd recommend? Ideally things easily available in the US in very small quantities.

author: ovnr
author_rank: Frequent Contributor
timestamp: December 07, 2017, 03:59:42 pm
content: Leaded.Really, most pastes work fine for hobby use. Even something likeChipquik SMD291works perfectly well.For smaller pitch stuff, you will want a paste with finer balls. But at that point, the stencil and pad geometry start to actually matter a fair bit too.

author: bson
author_rank: Unknown
timestamp: December 08, 2017, 10:03:59 am
content: Leaded, without doubt!

author: AllTheGearNoIdea
author_rank: Unknown
timestamp: December 09, 2017, 11:14:36 am
content: I recommend you don’t eat it.Leaded and don’t buy to much as it has a relatively short shelf life. I hide it at the back of the fridge behind all the greens that don’t get eaten. This may extend the shelf life one of my pots it’s year out of date but performs the same. I only use small amount for repair usually end up chucking it away.Chris

author: Azu
author_rank: Newbie
timestamp: December 19, 2017, 01:23:29 am
content: Leaded. Gem to work with compared to lead free.

author: nanofrog
author_rank: Super Contributor
timestamp: December 19, 2017, 03:33:13 am
content: Kester's products work extremely well IME.Between lead and lead-free, go with the lead basedEP256(35g syringe & 150g jar). If you need/want to buy some yourself,CML Supplyrepackages other Kester products as into hobbyist/repair tech friendly sizes.They also sell on eBay if you'd prefer the obfuscation that PayPal offers/use funds already available. Just note that international shipments are only available directly from their own website for those not in NA and would like to try it (though I'm not sure how competitive it would be price-wise vs. say Multicore/Loctite).For disclosure, the only affiliation I have with CML is as a customer.
Solder paste & stencil vs. tin & flux - Page 1
Forum section: electronics / beginners

author: Renate
author_rank: Super Contributor
timestamp: October 23, 2020, 12:30:18 pm
content: Things are getting smaller and I've not very much experienced in smaller than 0805.I see posts about soldering small chips with solder paste and stencils.It still seems difficult to get a clean stenciling.Also, ordering a stencil is a hassle.The few times that I've done small chips I've just tinned the pads with a soldering iron.Without the chip being there it's easy to blob the solder on without bridges.Then I liquid flux the pads again, stick the chip on and use a regular heat gun.Since the chip is the center piece it's the only thing on the board at that point and I don't have to worry about melting connectors.Any advice, suggestions?I wouldn't mind owning a reflow oven, but they all seem to be crazy sizes.I don't have the space or power for one of those T-962.It seems that there would be a market for 100 mm x 100 mm.

author: HB9EVI
author_rank: Frequent Contributor
timestamp: October 23, 2020, 02:05:31 pm
content: imho one major problem with solder paste is, that one uses too much of it; the proportions tin vs. flux is not the best; this is why I always stir up a small portion of solder paste with additional flux; the required amount of tin for a stable connection is really tiny, but its flux behaviour is very important -> more flux, less tinsuch a mix of paste and flux I just spread randomly over the pins to solder, put the chip on it and solder with the rework station. that practically always works without any manual rework with a solder iron. flux is really crucial for proper work. I also never use stencils.and don't use heat guns; their temperature settings is everything else than stable; and if you don't just have a QFN or a BGA chip, there is no need to heat anything else than the chip's pins; so you need a nozzle which matches the footprint of the chip
Solder practise LM358 - Page 1
Forum section: electronics / beginners

author: classiphil
author_rank: Newbie
timestamp: October 10, 2024, 01:49:02 pm
content: Hey there,I want to elevate my soldering skills and want to do it on a real circuit after practicing it on broken electronics already.May I swap in a TL072 for this LM358?Any other recommendations for lower noise?Thanks, guys.

author: magic
author_rank: Super Contributor
timestamp: October 10, 2024, 06:00:39 pm
content: For soldering practice you only need the footprint to match, so of course you can.But if this is one of those "real circuits" and it's supposed to continue working afterwards, it would make sense to first have some idea what this chip is doing there and why you want to change it for another one?There are various place where either of those will work, and various places where only one or the other will.
Solder rosin core 50 and 44 - what's the difference?? - Page 1
Forum section: electronics / beginners

author: tkamiya
author_rank: Super Contributor
timestamp: June 16, 2020, 02:20:53 am
content: I have been using Kester brand solders. My current stock of 63/37 (leaded) is getting lower so I was looking at new rolls. Apparently, what I have is rosin core flux 50. Then there is rosin core flux 44.On Kester's site there is some details on flux 44 but not 50, although its products use both. Is one better than the other in some ways? I am assuming these number represents formulation, not the amount of flux, correct?? What are the properties.I do anything from general electronics, RF, etc, etc.... all hand soldering.Can someone educate me on these?

author: Shock
author_rank: Super Contributor
timestamp: June 16, 2020, 10:51:52 am
content: Check the labeling on the spool you are looking at, if it is something like #50/245 I expect that 50 is the core size and 245 will be the flux type. With 245 the core sizes are 50, 58 and 66. As a percentage that is 1.1%, 2.2% and 3.3% flux core.https://www.kester.com/products/product/44-flux-cored-wirehttps://www.kester.com/products/product/245-flux-cored-wire
solder spindle - Page 1
Forum section: electronics / beginners

author: Jarred
author_rank: Newbie
timestamp: May 16, 2014, 09:42:05 am
content: Hey guys,I'm always having this problem with my Hakko solder spindle. It's really annoying, does anyone have any tips on how to stop this? or can suggest a better/different spindle?

author: John Coloccia
author_rank: Super Contributor
timestamp: May 16, 2014, 10:01:36 am
content: I have the dual spindle and it used to happen to me all the time, but now it doesn't anymore. I don't know what's different. As counter intuitive as it seems, try setting it up at an angle. That will put a little kink in the solder as you pull it out and will make it more difficult to push back and cause a mess. Little thing like thin really can be very annoying.

author: Jarred
author_rank: Newbie
timestamp: May 17, 2014, 03:16:55 am
content: good thinking thanks ill give it a try

author: Rigby
author_rank: Super Contributor
timestamp: May 17, 2014, 03:27:51 am
content: Don't yank the solder out hard enough to set the spool freewheeling. Or, find a way to add more rotation resistance so the spool can't turn without some sensible pull on the solder.

author: nanofrog
author_rank: Super Contributor
timestamp: May 17, 2014, 03:38:50 am
content: Quote from: Rigby on May 17, 2014, 03:27:51 amRubber band wrapped on the spindle should do.

author: peter.mitchell
author_rank: Super Contributor
timestamp: May 17, 2014, 03:55:34 am
content: Lots of things, use a wider spool of wire, tilt the guide upwards so there is more constant tension on the solder, move the guide closer to the spool, center the spool on the shaft so it doesn't move from side to side, ect ect ect.
Solder Squeegee - Page 1
Forum section: electronics / beginners

author: Seph.b
author_rank: Regular Contributor
timestamp: May 01, 2018, 06:40:01 pm
content: I have been doing my SMD stuff with a cheap reflow oven for some time now and want to start using stencils.I have my first stencil in and have a jar of solder paste on order, but I can't seem to find the tool to spread the paste. I find lots of small ones for BGA stuff, but not big ones to do a whole board in one pass.This first board is probably 2 1/2" inches wide.I am guessing most things from the hardware store would not work great.Anyone have any suggestions or links for me?Thanks.

author: grifftech
author_rank: Frequent Contributor
timestamp: May 01, 2018, 06:48:36 pm
content: old credit/gift card

author: Seph.b
author_rank: Regular Contributor
timestamp: May 01, 2018, 06:51:44 pm
content: Quote from: grifftech on May 01, 2018, 06:48:36 pmThat is what I was going to use until a got a proper tool. Will that really work in the long run?Also what do people use to clean up their stencil? Just rubbing alcohol?

author: BBBbbb
author_rank: Unknown
timestamp: May 01, 2018, 07:27:44 pm
content: If you don't have a card to spare these are cheap and can be useful:https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2057872.m570.l1313.TR0.TRC0.H0.TRS0&_nkw=10pcs+Plastic+Card+Pry+Opening+&_sacat=0Usually IPA or acetone for cleaning.

author: jmelson
author_rank: Super Contributor
timestamp: May 02, 2018, 02:39:13 am
content: I use a piece of .025" brass shim stock, and have been using it for about 10 years. Works great. I got a shower squeegee at Ikea and it also works. I was thinking about buying half a dozen of them and cutting them down to different sizes to match different boards, but haven't done it yet.Jon
Solder Station and surge protector - Page 1
Forum section: electronics / beginners

author: tony3d
author_rank: Frequent Contributor
timestamp: February 10, 2014, 08:33:36 pm
content: Is it a bad idea to plug a solder station into a surge protector? Does it limit the station's performance in any way? Is it best to plug it straight into the wall?

author: dr.diesel
author_rank: Super Contributor
timestamp: February 10, 2014, 08:38:07 pm
content: It will be fine assuming you're under the amperage of the surge protector, most solder stations pull very little current.I think my Hakko FM-206 with three irons is still < 400 watts when all three are heating.

author: GreyWoolfe
author_rank: Unknown
timestamp: February 11, 2014, 02:33:49 am
content: My Hakko 936 is plugged into a Belkin surge protector with all 6 sockets filled. The Belkin is plugged into an APC SmartUPS 1550with 3 more surge protectors running my entire workbench. Have had no issues with the Hakko or anything else test equipment wise.

author: tony3d
author_rank: Frequent Contributor
timestamp: February 11, 2014, 12:30:12 pm
content: Ok, thanks for the reply's.

author: dr.diesel
author_rank: Super Contributor
timestamp: February 11, 2014, 12:54:12 pm
content: Most surge protectors only consist of an El-cheapo circuit breaker and a couple of undersized piss ant MOVs. In the event of overloading, ie plugging in too much stuff, it's designed to disconnect all sockets from the mains (same as your main breaker panel). In the event of a drastic overvoltage, the MOVs are there to shunt the offending line to ground/neutral.For the most part, surge protectors are only good for port multiplication, rather than surge protection.
Solder Wire Flux Content - Page 1
Forum section: electronics / beginners

author: jnv108@gmail.com
author_rank: Newbie
timestamp: September 01, 2014, 04:41:01 am
content: I need to buy solder wire and this is very confusing. I would like to buy 0.5mm solder wire, but how much flux needs to be inside the wire?1% 2% 3%- Is 1.2% flux on the solder wire good enough for a beginner?[NB: I am planning to just play around with circuits, and teach myself some basic electronics. ]I am new to electronics and soldering ETC. I have just bought myself a Dick Smith Soldering ironhttp://www.dicksmith.com.au/tools-hobbyist/temperature-controlled-soldering-station-dsau-t2200

author: Fsck
author_rank: Super Contributor
timestamp: September 01, 2014, 04:51:35 am
content: most people will add flux any time they solder (either pen or bottle with a fine tip, etc) so it doesn't really matter in general.

author: jnv108@gmail.com
author_rank: Newbie
timestamp: September 01, 2014, 05:27:55 am
content: HiThanks for the reply.I will be getting a flux pen anyway. But what % would you suggest included in the solder wire itself?

author: Fsck
author_rank: Super Contributor
timestamp: September 01, 2014, 06:04:45 am
content: I use kester 44, which typically comes with 3.3% flux by weight.

author: DanielS
author_rank: Frequent Contributor
timestamp: September 01, 2014, 06:15:43 am
content: Quote from: jnv108@gmail.com on September 01, 2014, 05:27:55 amThe more flux you have in the solder itself, the less likely you are to need to add any in a typical soldering job. If you are going to solder on bare copper a lot, such as tinning copper wires, use the highest-flux solder you can find so extra solder will add extra flux to help solder wick all the way through. If you are going to be soldering mostly on tinned copper or will be applying your own flux either way, you can skip flux in the solder wire altogether.I have 3% rosin solder wire and practically never need flux for soldering unless the surface I am trying to solder to is in pretty bad shape - usually need to give it a good scraping first in those cases.

author: G7PSK
author_rank: Super Contributor
timestamp: September 01, 2014, 05:30:19 pm
content: You cant go wrong with "more flux the better" in the solder. Also particularly at first very fine solder is hard to manipulate and feed into the joint learn to solder using .9 solder go to .5mm as your skill improves.

author: David Hess
author_rank: Super Contributor
timestamp: September 01, 2014, 07:03:11 pm
content: The only time I would use solder with a smaller sized flux core would be in a production environment where the surfaces of the boards and parts are of a known quality. In any other application, I would use the largest flux size available.My favorite is Kester 44 with core size 66 which is 3.3% by weight.
solderin tip is too big (900M) - Page 1
Forum section: electronics / beginners

author: prAlex
author_rank: Newbie
timestamp: February 26, 2021, 04:43:23 pm
content: My 900M tips that I bought (fake Hakko) have an inner diameter of 4,5mm instead of 4mm. Could I put something inbetween the tip and the heating element like tin foil(aluminium)?

author: John B
author_rank: Frequent Contributor
timestamp: February 26, 2021, 07:03:14 pm
content: Aluminium foil will just make it worse. There will be very poor regulation of the tip temperature. Buy a genuine tip, clean and tin it after every use and it will serve you well for years.

author: BrokenYugo
author_rank: Super Contributor
timestamp: February 27, 2021, 05:34:23 am
content: I tried that once with aluminum foil, it oxidized from the heat and expanded enough I had to cut the tip apart to save the heater.It's a known problem with the knockoff tips, they work, but they're really best for finding what profiles you use most as not to waste money on expensive genuine tips you won't use.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 27, 2021, 07:34:50 am
content: Piece of copper sheet of correct thickness will help to some extent but really, the knockoff tips are bad anyway (not just the wrong diameter), just buy proper tips, they cost maybe $1-2 more than the counterfeits and will last for years in intermittent hobby use.

author: Refrigerator
author_rank: Super Contributor
timestamp: February 27, 2021, 09:12:53 pm
content: I've tried putting in aluminum from beer cans but it does oxidise and the heater eventually gets stuck.These days i wouldn't even bat an eye at these old tips because T12 tips are so much better anyways.T12 tips are easy to change (just pull out), you can hot swap them (without waiting to cool down) and they just perform so much better.Of course that would require a new, compatible soldering station but they're inexpensive so you might want to consider it.Other than that there's not many good options really, it's just a bad tip, try to not buy them again, i guess.Been there, done that, i still have some of those cheap crap tips somewhere in my parts bins and when i found them a few weeks ago while cleaning up it atually surprised me how bad these are, worse than i remember even.
Soldering (or otherwise connecting) down a hole - Page 1
Forum section: electronics / beginners

author: Skippy
author_rank: Contributor
timestamp: March 27, 2013, 06:33:45 pm
content: I've got an small LCD screen that one of the LED backlight cables has come out of. So now I've got a hole in the top of the LCD module. The hole is recessed, so the contact inside is inside the moduleI know the contact is in there, since I can stick a pin in the hole and touch a wire to the pin and make the backlight come on, but I can't get a soldering iron in there, and attempts of putting a wire with a blob of solder in and then heating the wire up have been a failure.Any suggestions, preferably without spending too much?

author: Fraser
author_rank: Super Contributor
timestamp: March 27, 2013, 06:45:39 pm
content: I would look at a mechanical solution rather than electronic soldering.I would consider the following:1. Gaining access to the connection by removal of insulation to expose the LED connection.2. Screwing a suitable sized self tapping screw into the hole until it presses against the LED connection. Then a wire may be attached to the screw head3. Use a thin piano wire or similar to form a spring contact that pushes down into the hole onto the LED contact.4. The assembly was some how manufactured, see if you can see how and then disassembke teh parts needed to access the LED connections.Fraser

author: SeanB
author_rank: Super Contributor
timestamp: March 27, 2013, 07:06:44 pm
content: Stick thin wire in there, and hold it in place after it is firmly placed with a tiny drop of quick setting epoxy to hold it to the board.

author: pickle9000
author_rank: Super Contributor
timestamp: March 27, 2013, 07:47:04 pm
content: Conductive epoxy on a wire or even better silver conductive ink with a drop of epoxy after it sets to hold it firm. The silver ink has less resistance than the epoxy.http://store.caig.com/s.nl/sc.2/category.174/.f

author: Fraser
author_rank: Super Contributor
timestamp: March 27, 2013, 08:47:04 pm
content: Its interesting that conductive epoxy has been mentioned. I once thought of buying some in the form of 'Wire Glue' that was advertised on e*ay. Then I read the feedback and some buyers described its properties as those of carbon mixed with glue and certainly not very conductive. I would be interested to here from anybody who has found a conductive epoxy that is truly conductive. The amateur chemist in me wonders how an epoxy/carbon mix can be very conductive. Silver track repair kits use an very thin acrylic base, heavily loaded with silver particles and inter particle contact produces continuity....epoxy is a slightly different matter due to consistency and conductive content. Its more like a composite resistor.Fraser
soldering 1.27mm pitched connectors on edges  - Page 1
Forum section: electronics / beginners

author: ag123
author_rank: Contributor
timestamp: March 20, 2017, 06:12:29 pm
content: hirecently i got a few of these nrf51822 boards (nrf51822 is a cool bluetooth le 'solution')http://www.ebay.com/sch/i.html?_odkw=nrf51822&_sop=15&_osacat=0&_nkw=nrf51822&_sacat=0the trouble is that the pads for pins on the edge is spaced at 1.27mm pitch, they are somewhat too closely spaced would probably need to 'breakout' further to say 2.54mm pitch to work more conveniently say to patch 'dupont' connectorsinitially i looked at these single row 'header strips'http://www.ebay.com/sch/i.html?_odkw=1.27mm+pitch+connector&_sop=15&_osacat=0&_nkw=1.27mm+header+strip&_sacat=0however, the header strips don't really solve the problem as they are still spaced closely and seemed needs an 'interface board' to breakout furtheri'm now thinking about using ribbon cables insteadhttp://www.ebay.com/sch/i.html?_odkw=nrf51822&_sop=15&_osacat=0&_nkw=1.27mm+ribbon+cable&_sacat=0how do you normally use these tiny boards? what are the good ways to patch those edge connecting pads? would it be difficult to solder wires to those 1.27mm pitched connecting pads given the close spacing? i'm thinking that even a little more solder may just short adjacent connectorsthanks much in advance

author: mubes
author_rank: Regular Contributor
timestamp: March 20, 2017, 06:19:44 pm
content: With a steady hand you can easily patch Dupont breakout leads to these. A blob of solder on the half crown, a tinned lead end cut off to about 1.6mm and then connect one to the other with the iron. Not a production solution, but wrapped in self-amalgamating tape it's surprisingly durable. On a plane right now but will post example pics later.Dave

author: ag123
author_rank: Contributor
timestamp: March 20, 2017, 07:45:43 pm
content: thanksin addition found some interesting and useful article from sparkfun about ithttps://learn.sparkfun.com/tutorials/how-to-solder---castellated-mounting-holesand found yet another cool article about ithttp://hackaday.com/2015/02/09/castellated-breakout-is-pitchin-brilliant/http://black-electronics.com/blog/2mm-headers-to-2-5mm-header/

author: mubes
author_rank: Regular Contributor
timestamp: March 21, 2017, 12:14:53 am
content: OK, this was the kind of thing I mean. This is a UWB Radio. Once it's wrapped in rubberised tape it's pretty much completely hardy.DAVE
soldering 16mm copper LED pcbs to a piece of flat copper - Page 1
Forum section: electronics / beginners

author: amlu
author_rank: Contributor
timestamp: January 16, 2019, 09:27:21 pm
content: Higot some new leds to mount in a floodlight enclosure, they are mounted on their little pcb bases, rather than mess around with drilling and screws i thought it may be a good idea to get a chunk of flat copper strip, solder the pcbs to it, then mount the strip on aluminium heatsink with thermal paste applied.https://www.aliexpress.com/item/2pcs-5W-5050-Ultra-Violet-UV-Purple-XML-365nm-380nm-390nm-420nm-High-Power-LED-Emitter/32676633451.html?spm=a2g0s.9042311.0.0.31584c4d2rbNwJhttps://www.ebay.co.uk/itm/3-MM-thick-COPPER-SHEET-PLATE-guillotine-cut-many-sizes/273239735520?hash=item3f9e5b7ce0:rk:5:pf:0&varsomething along the lines of heating the copper from the bottom with small blowtorch, spreading some solder on it, placing the leds on, letting it flow for a bit then taking off the heat...doable? will it cool quickly enough not to damage the leds?