Short list of used analog scope. Any experience please? - Page 1
Forum section: electronics / testgear

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 22, 2025, 10:02:53 pm
content: Hi everyone.After having used my ok Gould - Advance Instr. 10 mhz analog scope for around 5 years, which served me ok for most stuff (there were times I wish I had a more capable machine, around digital Ics and clock), i’ve decided to upgrade, because now it’s quite unreliable (not unfixable in anyway) and anyway it’s not that good. I will gift it to a friend that has none. learnt my way around itFrom what I’ve read in here (very very trustworthy experienced forum members) and read on some online articles, I think for my use (music and audio devices) it would be better value to remain in the older analog domain (50mhz +) since I need good trace even in very low frequencies (around 20-30 hz) but occasionally I would like to be able to test on and around (older) digital chips in audio devices (synths - dsp - dac- clock etc). It’s also a matter of taste liking the built of older devices.I want something as good as possible and straightforward to operate (not that I’m scared of menu diving, but who needs it), reliable and repairable ( my main reasons to avoid cheap modern dso and prefer simpler devices).So I’ve made a short list of some good value oscilloscopes I can find in the EU market for under 150 euros which is my max budget.My short list is:Tektronix 2225Tektronix 2213ATektronix TDS 340 - tds 320 (digital old? Bad era for digital maybe?)Hameg hm 605 (604 can be found too)Philips Pm 3050 (analog-digital? Bad era for digital maybe?)Kikusui Cos 6150 or 6100.I would like your opinion and advice on any of the models i include you may have any work experience on. Or advice on similar models.Please don’t advice on modern cheap digital or usb devices, in anyway (unless somebody give me one for free), and stuff out of my budget.Thanks in advancePs I mistakenly started a similar thread in the beginner’s section some hours ago. I apologise to the forum moderators for that and not having checked the appropriate forum beforehand.

author: adam4521
author_rank: Regular Contributor
timestamp: July 23, 2025, 06:13:55 pm
content: The supply on open market is getting a bit dry and a lot of what is offered now has ‘issues’. For the budget you have you should hold out for perfect, rather than compromising. I have/lent/had a 2245A for example, which has auto setup and cursor features on top of an analog scope, no defects at all. For repairability and comparative new-ness, Hameg. If you are tempted by ‘old digital’, I think it has to be 54621/54622.But you are on the right forum for finding a member that might be able to ‘sort you out’, economically.

author: tggzzz
author_rank: Super Contributor
timestamp: July 23, 2025, 06:44:04 pm
content: Please do not duplicate threads; it simply wastes people's time when they repeat something already said in the other threadhttps://www.eevblog.com/forum/beginners/advice-regarding-used-analog-oscilloscopes/msg5987287/#msg5987287

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 23, 2025, 07:08:39 pm
content: Quote from: tggzzz on July 23, 2025, 06:44:04 pmSorry about that tggzzz. If you read my post’s ps I mentioned that and I apologised. I felt like I started the thread in the wrong forum. Not very familiar with the different forums in here.

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 23, 2025, 07:25:48 pm
content: Quote from: adam4521 on July 23, 2025, 06:13:55 pmThanks for the reply and advice. The particular models you suggest are out of my budget at the moment.

author: tautech
author_rank: Super Contributor
timestamp: July 23, 2025, 08:37:54 pm
content: Several of the TDS models have their particular issues, 200 models can suffer from broken BNC's resulting from poor design and abuse.Others have issues from the bad cap days and cap leakage can damage PCB's beyond repair.A 1000 model I was given had no display, traced back to a failed backlight inverter and its primary push-pull bipolar stage and its RC that set its operating frequency. The C had drifted into the pF region.Instead you should save up to get something newer and more reliable.

author: tggzzz
author_rank: Super Contributor
timestamp: July 23, 2025, 08:42:47 pm
content: Quote from: tedsorvino on July 23, 2025, 07:08:39 pmAccepted.Knowing where to put something in a simple hierarchical tree is a standard problem. In general there will be several places it could reasonably go, so just pick one. The best that can be hoped for is to avoid putting it in a stupid place.In a library, a book on batteries might be in DIY or electrical or car repair or... but not in embroidery.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 23, 2025, 08:46:18 pm
content: Quote from: tedsorvino on July 22, 2025, 10:02:53 pmI have to agree with tautech. There's some other things you need to consider. Yes, you can get an old analog scope for $150. Then you can spend $300 or more fixing it when you find out what problems it has.Or you can save up a little bit and get an SDS802X HD or SDS804X HD for $350 to $450 depending on how many channels you need. It's a surprisingly powerful modern scope for a ridiculously low price considering its capabilities. Also, it comes with a warranty.If you like to work in audio domain, you will also like having a nice FFT and Bode plot functions.Browse through this thread and see what it's capable of:https://www.eevblog.com/forum/testgear/sds800x-hd-review-demonstration-thread/Thanks,Josh

author: David Hess
author_rank: Super Contributor
timestamp: July 23, 2025, 09:35:10 pm
content: Quote from: tedsorvino on July 22, 2025, 10:02:53 pmI doubt it matters. A modern DSO would have the advantage of FFT capability which can be used for distortion measurement, at least for higher levels of distortion.QuoteI know a lot about the Tektronix models so will comment on them.Tektronix 2213A - This is a replacement for the older 60 MHz single delayed timebase 2213, based on the 100 MHz dual delayed timebase 2235. The 2215A is a 60MHz dual delayed timebase 2235. The single delayed timebase of the 2213/2213A is unusual but useful if you need limited delaying capability.Stay away from the original 2213 and 2215 unless you find a working one at a good price; their older design has problems.The 2235 led to lots of variations including the 2236 which has a built in multimeter and gated universal timer/counter, and the 2230/2232 combination analog and digital storage oscilloscopes. There are also single timebase and 60 MHz versions of these DSOs.Tektronix 2225 - This is the first of a completely different series than the 2235 with a 50 MHz bandwidth. It has a single timebase, but with alternate magnification and no delay capability. The 2225 has a 5 MHz bandwidth limit allowing low noise 500uV/div sensitivity which might make it uniquely useful for audio applications.Tektronix TDS340 - TDS320 - I have some experience with the TDS420 series. These are all raster CRT DSOs and there is nothing wrong with them except their age and lack of full documentation.Acceptable analog models, but keep in mine that these are all old and likely to require some maintenance:2213A 60 MHz 2235 with Single Delayed Timebase2215A 60 MHz 2235 with Dual Delayed Timebase2235 100 MHz with Dual Delayed Timebase2225 50 MHz with Single Timebase, Alternate Magnification, and 500uV/div SensitivityI have a pair of 2230s and 2232s and regularly use a 2232, but these are combination analog and digital storage oscilloscopes based on the 2235. Buying a known working one could cost as much as a new low end DSO.

author: nctnico
author_rank: Super Contributor
timestamp: July 23, 2025, 10:36:21 pm
content: IMHO any cheap DSO will be an improvement over an analog scope or an old digital one just due to age and potential problems that come with age. The ability to stop signals and look low frequency signals is killer.

author: tautech
author_rank: Super Contributor
timestamp: July 23, 2025, 10:54:10 pm
content: Quote from: nctnico on July 23, 2025, 10:36:21 pmTo a point.....Waveform capture is just the start but ease of saving screenshots takes things to another level for documentation/sharing or posting online when you see something you don't understand and need advice.My first real DSO was a TDS2102B, selected for its ability to save screenshots to USB and for simple tasks I might still be using it but it died from corrosion to a IC pin due to it being top vented and allowing dust to settle inside it and humidity did the rest.Never been a fan ofanythingtop vented since......

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 23, 2025, 11:02:41 pm
content: Thanks all for your replies. Mr Hess post clarifies a lot of things about the Tektronix models.

author: David Hess
author_rank: Super Contributor
timestamp: July 24, 2025, 01:29:08 am
content: Quote from: nctnico on July 23, 2025, 10:36:21 pmI disagree because many of these old DSOs have dual delayed timebases allowing operating modes like trigger after delay not supported by cheap modern instruments. Their age is somewhat made up for with full documentation, making them easier to maintain. They stop signals and look at low frequency signals just fine.

author: porter
author_rank: Regular Contributor
timestamp: July 24, 2025, 05:33:12 am
content: Something to keep in mind; the Tektronix 2225 and 2235 have RIFA caps.

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 24, 2025, 05:56:31 am
content: Quote from: porter on July 24, 2025, 05:33:12 amI’ve read about it. Yes they are prone to bad things, but it doesn’t happen that frequently.In my eyes they look beautiful, but it’s a good practice to take them out beforehand.

author: lowimpedance
author_rank: Super Contributor
timestamp: July 24, 2025, 06:40:16 am
content: Quote from: porter on July 24, 2025, 05:33:12 amHave had two 2235a scopes pop their IEC inlet filters, so it would be prudent to change if you decide on this series.However when looking at your local used market , what brand do you see the most of ? (Tektronix, Hameg etc). That could be more the deciding factor.I would steer clear of any Philips CRO's, documentation and spares would be harder to come by.If the 2000 series tek scopes are likely then try and get the 'A' suffix over the non A.I have used the 2235A and is a good performer. Compact enough and generally reliable with no fan, although mechanically/electrically there is provision for it.It does run a bit hot so if you live in a hot area you might consider adding the fanThere might also be a need to replace the power supply electro's, best to check while doing the inlet/rifa caps.

author: Smokey
author_rank: Super Contributor
timestamp: July 24, 2025, 07:29:58 am
content: um.. ok.. I'll post this here too...A no name Chinese AliExpress "scope" is in many ways significantly more useful than those boat anchors in 2025. And I'm a collector of boat anchors (but mostly power supplies and meters).Get a used rigol ds1000z.

author: Aldo22
author_rank: Super Contributor
timestamp: July 24, 2025, 08:50:21 am
content: Quotes fromhttps://www.eevblog.com/forum/beginners/advice-regarding-used-analog-oscilloscopes/msg5988233/#msg5988233Quote from: EvgenyGThat misses the point imo.If you buy an old CRO for budget reasons, then 55€ (minimum) for a spare part is too much.If you don't care about the cost, it's a different story.If it's your only scope, then you want to repair it promptly and not wait for a flea market opportunity.I would buy a reasonably modern DSO as a first/sole scope if I had a tight budget.

author: nctnico
author_rank: Super Contributor
timestamp: July 24, 2025, 11:16:49 am
content: Quote from: David Hess on July 24, 2025, 01:29:08 amYou can either put the trigger point outside the screen or use zoom mode to do the same. The nice thing about a DSO is that the trigger point doesn't need to be on screen. Maybe some older, cheap pocket DSO doesn't have this but the more modern incarnations of the cheap pocket scopes start to become packed with functions.

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 24, 2025, 11:38:02 am
content: Quote from: lowimpedance on July 24, 2025, 06:40:16 amThanks for the reply. Actually Philips, Hameg and then Tektronix are the most common ones. European brands first in EU. HP are not popular for example.

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 24, 2025, 11:41:48 am
content: Quote from: Aldo22 on July 24, 2025, 08:50:21 amI appreciate your reply but obviously you haven’t read my original post. Not my first scope and possibly not my sole. And parts..are parts….some cost peanuts, some as you said cost more than the unit.

author: David Hess
author_rank: Super Contributor
timestamp: July 24, 2025, 06:29:05 pm
content: Quote from: lowimpedance on July 24, 2025, 06:40:16 amI worry less about the RIFA capacitors because they are so easy to replace, or do without, and should not damage the oscilloscope.QuoteThe old Philips oscilloscopes are also fully documented, but maybe not as reliable, like the original 2213/2215. A larger problem may simply be that they are not as common.QuoteThe 2235 and 2236 have A versions which are basically the same as the non-A versions except with a slightly different parts selection, meaning that they updated them to the 2232 analog/DSO standard. Their big advantage is that they could be up to up to 7 years newer. The 2232 also has an A version, but it is only distinguished by year and serial number, and I think it only involved a change in the high voltage resistors. The 2221 analog/DSO was based on the earlier 2230 analog/DSO design, and the 2221A analog/DSO was based on the later 2232, so they have major differences.The 2213A and 2215A mirror the older 2235.If you want to consider the 2235 analog/DSO versions, consider the 100 MHz 2232 Dual Timebase, 60 MHz 2224 Dual Timebase, and 100 MHz 2221A Single Timebase. I would avoid the others because they are based on the 2230 analog/DSO which is an older weird design.Quote from: nctnico on July 24, 2025, 11:16:49 amIt is not the same thing. Trigger after delay removes all jitter between the first trigger point and the display while operating in real time, whether the jitter comes from the DSO or the signal source.In the past it was used to display a single line of a video field without jitter, or a single sector of a magnetic disk track without jitter. I have sometimes used it to display the reverse recovery waveform of a switching power supply or mixed signal switching circuit without jitter from the duty cycle changing.In practice this feature is rarely used or needed now, but it does come in handy sometimes. I would never buy an oscilloscope just for it unless I had a specific use for it.

author: tatel
author_rank: Frequent Contributor
timestamp: July 24, 2025, 08:12:06 pm
content: Quote from: tedsorvino on July 22, 2025, 10:02:53 pmTo me, Hameg would be the most sensible option, they are easy to be found, and are made from off-the-shelf components. At least up to the 605 model, I don't know about newer ones. So you won't be stuck, should an unobtanium part fail. I got a bunch of 203-303-604-605 because I wanted to get inside and learn about fixing electronics. And to not worry about blowing my DSO should I make a stupid mistake while looking at some PSU, or something like that.If not for that, there's little doubt I paid too much for most of them. Unfortunately life got in the way and they are still waiting for me to have time to put up a new workshop (slow progress) and get into it. However I'm not selling any of these before getting all the fun I planned to get. I got a 203-7 the cheapest, for 25€, but I paid more like 75-100 for most of them. The best score was a good working 605 full equipped, with half a dozen probes, adapters, leather case... for those 150€. It took a couple of years to appear on a local second hand web. It was gifted to a (now old) man that never used it in about three decades. I would say, forget about finding anything like that on ebay for 150€+shipping.A couple of years ago, It wasn't easy to find anything on ebay europe for 150€. Prices in the US and UK are lower, even quite a bit lower, but then you have to add taxes, shipping... I would suggest to look for something in the EU. Should you want to get anything from outside the EU, it has to be shipped by ebay shipping or you'll be screwed when the courier asks an insane amount of money as fee for customs paperwork. Now EU prices seem to be lower than back then, but they still look a bit crazy. You'll probably find they ask about the same amount for, say, a 203 than for a 605. So you should look for a 605, which has about the same capabilities than a 604 but is like a decade newer.Probability of finding a perfectly good working one is almost zero, I would say. Bare minimum, they will need switch cleaning and adjustment. Even that 605 needs that. Perhaps it would be wise to keep your current oscilloscope until you are satisfied with anything you could purchase second hand. You could need it to fix the new to you one.I'm planning to keep just one each 203 and 605 to look at PSUs (203) and the 605 because I like it, as vintage collectible toy.So far my answer to your question. But my best advice would be: if at all possible, wait, save your money, and get one of these new entry level 12-bit Siglent DSOs, and, if you are planning to look at digital, perhaps a DSLab logic analyzer also. We are in 2025, man. An old analog 50 MHz oscilloscope won't make so much for you. My first oscilloscope was an entry-level 8-bit 4-channel DSO. While I'm still happy with it, looking at the prices asked today for second-hand 8-bit DSOs, compared to the price for new, 12-bit ones, I wouldn't buy a second hand DSO for say, about 300€ + shipping. Not even high on drugs. I wouldn't buy any of these cheap toyscopes or lower tier models either, except the cheapest ones, and that just to have some kind of portable, cheap, not to worry about, still useful tool in the field, as in looking at something in my car (I did got a Zeeweii DSO154Pro which is a dirty cheap "toy").Of course you will need like 5-6x your budget to get one of those 12-bit things and a logic analyzer. I think you'll get like 20x the bang for your bucks. But it's up to you.Anyway, enjoy, and good luck.

author: David Hess
author_rank: Super Contributor
timestamp: July 24, 2025, 09:58:59 pm
content: Quote from: tatel on July 24, 2025, 08:12:06 pmAt least for Tektronix, the unobtanium parts like hybrids and custom ICs are the most reliable parts. Potentiometers and switches are always a problem with old instruments. Specific models have problems, like the CRT vertical amplifier load resistors on the 2213 and 2215 which run hot and fail, a problem which was fixed in the 2235. The high voltage resistors in the focus chain sometimes fail, but can be replaced with modern parts. Of course old aluminum electrolytic capacitors are always suspect.The 2235 series has a problem with its switching power supply which can cause the switching transformer to fail, but I have never had a broken one to examine so I do not know what causes it. I suspect some combination of worn out aluminum electrolytics causes the power supply to oscillate and overheat the transformer somehow.QuoteI am not sanguine about low cost 12-bit DSOs. It seems like a nice feature but I think it is more about marketing, with one exception. They do not have lower noise unless being compared to modern 8-bit DSOs which have excess noise to start with, and their dynamic performance is no better. This is because these are limited by the high impedance front end and not the digitizer. Integral non-linearity is usually no better.Where they should have an advantage is dynamic range for FFT spectrum analysis, but limitations in integral non-linearity will result in only marginal improvements to spurious free dynamic range, so distortion measurements are only slightly better.I would be more interested how well the user interface works.

author: lowimpedance
author_rank: Super Contributor
timestamp: July 25, 2025, 12:01:42 am
content: Quote from: David Hess on July 24, 2025, 06:29:05 pmCertainly, I didn't worry about them either, until after the 'explosion' with the associated stink but also in one case a plume of metal film flakes spewed over the mains area of the PCB !Of course up to owners to judge for themselves.Quote from: David Hess on July 24, 2025, 06:29:05 pmMy one experience of a Philips CRO , which are generally less uncommon here, was of a unit full of custom hybrids with difficult access and complex construction leading to unreliable operation.Not impressed so that probably has coloured my opinion, still if Philips CRO's and parts are more common where the OP is then sure he should consider this brand as it may well be cheaper for him.Also I have come across other Philips equipment and documentation was also limited for those too, at least from my googling of the usual suspects etc. YMMV.At the end of the day , and discussion, Its clear the OP really wants an oldie CRO and he has three brand choices that are common in his locale.CRT CRO's maybe old news but they're still very useful tools.When he has purchased one , a little bit of maintenance will more than likely be needed and when done ,hewill be happy !!

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 25, 2025, 05:09:17 am
content: Thanks all for the replies so far. Useful and constructive input from all of you.

author: Fungus
author_rank: Super Contributor
timestamp: July 25, 2025, 06:37:24 am
content: Everybodylikesthose old analog 'scopes with their green glows and clicky switches but they're all starting to fail now and modern DSOs can do so much more that it's just not worth maintaining analog 'scopes for work use.It's like driving a Ford Model T. They look cool and some people might do it but most don't, and for the same reasons.

author: tggzzz
author_rank: Super Contributor
timestamp: July 25, 2025, 08:40:49 am
content: Quote from: Fungus on July 25, 2025, 06:37:24 amForworkuse I agree, except in certain unusual circumstances. Time is money, unless you have an idiot boss.For amateur use where resources are constrained, a working analogue scope can still be very useful, any scope is better than no scope, and the learning curve is lower/shorter. e.g it is better to have an old cheap scope and a PSU rather than a shiny new scope and no PSU

author: J-R
author_rank: Super Contributor
timestamp: July 25, 2025, 09:44:51 am
content: I vote for purchasing something based on opportunity. If you see a great deal on a scope that fits your purpose, then just buy it.Frequently the problem with doing too much research on what to buy results in not being able to actually find it because everyone ran out and bought them all, or the price jumped due to demand.

author: tedsorvino
author_rank: Regular Contributor
timestamp: July 25, 2025, 07:14:17 pm
content: Thanks all for the input. I do appreciate your time and effort. Think I’m covered.All good and useful advice. All much clearer.Timing and available budget matters when it comes to good bargains of all kind.Cheap DCOs will always be out there and (as usual with digital technology) they will keep on becoming more common, better and cheaper (like DMMs and computer technology).I’ll meet some of you in some of my (very probable) future questions regarding troubleshooting stuff or something (like I occasionally do) in here. Thanks again.

author: viktor63
author_rank: Contributor
timestamp: July 25, 2025, 08:04:19 pm
content: I would choose modern devices GW Instek GOS-652G, GOS-630, GOS-635 which are sold in Europe under the brand Voltcraft, I bought on ebay.de Voltcraft 630 for 80 eu

author: UnijunctionTransistor
author_rank: Frequent Contributor
timestamp: July 25, 2025, 08:08:44 pm
content: Jim Williams, fabled analog guru of Linear Technology fame, used analog scopes almost exclusively.But he passed away over 14 years ago, and there was a larger availability of analog scopes in very decent condition.Additionally, and this is important, we don’t have Jim’s analog expertise. At least I know that I don’t.Analog scopes will require much more mental effort to obtain even basic waveform information. When was the last time you carefully aligned a waveform with the graticule, counted divisions and estimated subdivisions, multiplied it by the timebase (making sure it was in the CAL mode) and then took the reciprocal to obtain the frequency?

author: tautech
author_rank: Super Contributor
timestamp: July 25, 2025, 08:13:36 pm
content: Quote from: tedsorvino on July 25, 2025, 07:14:17 pmOne needs to ask where have you been the last 20yrs.Then one needs ask where you can buy a new CRO these days......the world has moved on.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 25, 2025, 08:19:52 pm
content: Quote from: tautech on July 25, 2025, 08:13:36 pmPretty sure he meant DSOs getting cheaper and more capable.That's wrong though, especially the DMM analogy. The same model DMMs actually got more expensive without added features or changes.

author: tautech
author_rank: Super Contributor
timestamp: July 25, 2025, 08:37:57 pm
content: Quote from: KungFuJosh on July 25, 2025, 08:19:52 pmYup but he got the lingo wrong....is a DCO ?As you well know even the cheap SDS802X HD will blow the socks off most old CRO's.Member UnijunctionTransistor summed it up nicely.

author: KungFuJosh
author_rank: Super Contributor
timestamp: July 25, 2025, 09:35:42 pm
content: Quote from: tautech on July 25, 2025, 08:37:57 pmMust have been a soft C

author: Fungus
author_rank: Super Contributor
timestamp: July 26, 2025, 04:22:44 pm
content: Quote from: tggzzz on July 25, 2025, 08:40:49 amNo argument there. Even the $30 Zeeweii I keep in my case has saved me on occasion.

author: David Hess
author_rank: Super Contributor
timestamp: July 26, 2025, 05:05:24 pm
content: Quote from: KungFuJosh on July 25, 2025, 08:19:52 pmDSOs gained functionality and performance while decreasing in cost because they could take advantage of increasing integration; memory and high performance logic became less expensive. Even flat screen displays became less expensive and lower cost over time.Multimeters could not take advantage of this. Even delta-sigma ADCs are not less expensive than the integrated ADCs they replaced.The above however does not apply to the firmware of a DSO. Many modern DSOs produce worse results than early DSOs, like my ancient Tektronix 2440.

author: nctnico
author_rank: Super Contributor
timestamp: July 26, 2025, 05:28:09 pm
content: Quote from: UnijunctionTransistor on July 25, 2025, 08:08:44 pmI do that to get a quick estimate regulary. Quicker than using the cursors.

author: tedsorvino
author_rank: Regular Contributor
timestamp: August 01, 2025, 10:42:52 am
content: Thanks again everyone. My case is complete.I bought a very well maintained Hameg HM 1007 for 100 euros. Good value I think (of course not on ebay). So far so good. Never dealt with digital oscilloscopes, so having something like a digital side with memories for the measurements is a good add on. But I don’t really feel like I’m used to things like that.It has a million buttons on it (some normal ones- some for tv - some for measurements )nI will explore them (if needed) and I’m sure I may find a couple of useful things for my needs.There is also an arduino add on for that (useful with a raspberry p- but not necessary since it can easily cost up to 50) for measurements like a modern dso (there is also a hameg old pc interface - but I don’t want pcs around) Don’t know…maybe I’ll think about it.The basic things I always use work flawlessly and it’s definitely more reliable, more efficient and easier to operate than my old 10mhz Gould. At the end of the day I’m not a lab kind of person, so i guess this system goes far beyond my needs.No need to compare it with cheap modern ones. It is what it is and I guess it will serve me well as long as it last (the maintenance is not that easy - but still not impossible especially if one is not scared of smds - but I hope I won’t need to go there at all).Ps. I was meaning DSO and not DCO (but coming from a synth background I use this term daily - I do prefer old analog ones, to software synths or digital ones - dco means digital controlled oscillator). :-)