First Oscilloscope buying from ebay - Page 1
Forum section: electronics / testgear

author: cprobertson1
author_rank: Frequent Contributor
timestamp: January 25, 2014, 08:44:43 pm
content: Helloo thar ladies and gents!Im looking to buy my first oscilloscope and I've got a number searched out which look to be in reasonable order.One in particular seems to have what the buyer describes as "pulse" (i.e noise) after powerup - apparently for a few minutes - seems to think they're caused by bad caps.http://www.ebay.co.uk/itm/191041979880?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649Anybody care to opine on how easy it would be to fix? £30 is not to be sniffed at if I can fix it for another £10-20

author: electronics man
author_rank: Frequent Contributor
timestamp: January 25, 2014, 08:53:41 pm
content: If its not then you could ge it for parts

author: JoeO
author_rank: Frequent Contributor
timestamp: January 25, 2014, 08:59:47 pm
content: It depends on the experience of the person repairing the oscilloscope.

author: cprobertson1
author_rank: Frequent Contributor
timestamp: January 25, 2014, 09:02:58 pm
content: A, very true! I'll still be needing an oscilloscope though, don't want to waste too much money (I have £100 budget! xD)Indeed! AS for my experience...Eh... never repaired an oscilloscope before: but I'm competent and clean when it comes to soldering xD

author: Andy Watson
author_rank: Super Contributor
timestamp: January 25, 2014, 09:13:12 pm
content: Can you find a service manual, or at least a circuit diagram? If not - don't touch it - unless you just want it for a tare down. It is very likely to be a simple and cheap fault to correct (might even be that it's working - where are the other ends of the probes?), but without a circuit and other test equipment you could be stumbling around in the dark.

author: cprobertson1
author_rank: Frequent Contributor
timestamp: January 25, 2014, 09:52:59 pm
content: Looks like I can get circuit diagrams: having trouble finding a full manual though - any suggestions on places to look?Ps - forgot to put the model name down! Tis a Crotech 3133 (I can get parts of the manuals for the 3131 and 3132 but I've no idea how they compare: I'll be able to find a copy somewhere though - there are a few manuals kicking about on ebay I think).Im messaging Crotech now to see if they'll have anything

author: picofarad
author_rank: Regular Contributor
timestamp: January 25, 2014, 10:47:13 pm
content: It depends on how much repair experience do you have. If you'll lucky, you can to fix the scope simply changing some components (capacitors, diodes, transistors), but otherwise, especially without an accurate schematic, the troubleshooting work may make you crazy!Anyway, for less than 20£ you can salvage a ton of very useful parts.

author: cprobertson1
author_rank: Frequent Contributor
timestamp: January 25, 2014, 11:12:59 pm
content: I think I'm going to leave that one; if I'm wanting spare parts there are apparently ebay sellers who specialise in dead electronics including plenty of dead oscilloscopesI can't find a manual anywhere and googling has revealed several folks on other forums asking the same question - where is the documentation!Currently browsing the ebays for other ones that won't require hackerage to make them work!Anybody care to opine on these? Any I should just ignore right off the bat?Thanks for your help btwGould 4074 DSO 4 Channel OscilloscopeHewlett Packard 180A Oscilloscope 1801A Dual Channel Amp 1821A TimebaseScopex 14D-15 OscilloscopePhillips 3243 Oscilloscope 32 MHZTektronix 453 Dual Trace OscilloscopePhilips PM3302 Oscilloscope PM 3302/001Hameg 20MHz HM 203-4 Oscilloscopehitachi v212 20mhz oscilloscopeGould 1420 - Oscilloscope + ManualHewlett Packard 1744A Twin channel OscilloscopeGould OS 255 - OscilloscopeISO tech isr620 - Oscilloscope

author: KJDS
author_rank: Super Contributor
timestamp: January 25, 2014, 11:32:00 pm
content: I've just tested a Trio CS-2210 and it's working ok.Yours for £60 including delivery to mainland UK including a couple of probes.

author: TopLoser
author_rank: Unknown
timestamp: January 25, 2014, 11:36:42 pm
content: Quote from: KJDS on January 25, 2014, 11:32:00 pmKJDS is a quality guy. Brilliant packing, nice equipment and knows what he's on about. Snap his hand off!

author: grumpydoc
author_rank: Super Contributor
timestamp: January 26, 2014, 12:04:04 am
content: I've a Hameg 203-6 but can't go quite as low price-wise as KJDS, yours for £80. I reckon it's the better 'scope but I am biased. KJDS is a reliable chap though - you shouldn't have any qualms about buying from him.As to the list of 'scopes on ebay, quite a long one, but here goes:The Gould 4074 has some faults but I'm inclined to agree with the seller's diagnosis that its the character generation and might not affect the actual operation that much. It might even stay at a lowish price because of this.The HP180A is a bit old and cruddyThe 'scopex I wouldn't touch with a barge pole at that price. Maybe £9.99The Phillips 3243 - yeah that's OK if it stays below £50 including postage but there are no photos of a trace so I'd probably steer clear.The Tek 453 - don't know much about these. Small dinky "ultra portable" (for the 70's) 'scopes. At least it has a trace. Again probably OK if it doesn't go for too many £££'sThe Phillips 3302 - Naw, early digital I believe. Good as a door stop possibly.The Hameg 203 - sound basic 'scope but that one looks a bit rough and there are no photos of it doing anything.The Hitachi - a bit battered at the back but it does appear to work. Again OK if the price doesn't go too high.The Gould 1420 - if that's an OS1420 then it's an early digital so probably not all that much cop. That said there is a trace and there's at least a user manual online so probably one of the better ones in your list. I think £50 is a bit too much though.The HP 1744A Analogue storage 100MHz. Actually the best specified 'scope in your list and definitely worth £4Not sure how muchmorethan £4 it might be worth - analogue storage CRTs need love and attention and we haven't seen that this one works.Gould 255 - Yeah, I suppose, I'd prefer if the price was a few quid less.IsoTech isr620. Pretty much the same comment as above. Magnified by the fact that the isr620 is averybasic 'scope.Out of your list I'd be almost inclined to pick the slightly faulty Gould DSO (with the caveat that the character generator might easily be about to die totally).At the moment cheap 'scopes on ebay UK are crap I'm afraid. The same vendor as the isr620 and a couple of the others in your list has a Hameg HM203-6 which might be worth a look.

author: TopLoser
author_rank: Unknown
timestamp: January 26, 2014, 12:34:15 am
content: Or there's always this option... seller's a nice chap might even drop the VAT for cash and carry Sheffield area!https://www.eevblog.com/forum/buysellwanted/fs-(uk)-gw-instek-72-6805-scope-and-signal-generator/msg324663/#msg324663Might chuck in a couple of probes as well if the winds in the right direction...

author: cprobertson1
author_rank: Frequent Contributor
timestamp: January 26, 2014, 12:56:41 am
content: Oh, wow guys - thank you ever so much! Ill get back to you in the morning - my phone is having ram problems and isnt any good for browsing the net at the moment - but thank you so much for the in-depth replies!

author: cprobertson1
author_rank: Frequent Contributor
timestamp: January 26, 2014, 11:26:42 pm
content: I kinda want one ofthese... JUST to turn into a desk clock...

author: PaulAm
author_rank: Frequent Contributor
timestamp: January 27, 2014, 12:07:46 am
content: The Tek 453 is a dual trace 50 MHz scope with delayed sweep. Depending on when it was built it may have either FETs or nuvistors in the front end. It uses a vacuum tube HV rectifier. It's a pretty rugged and reliable scope with full documentation available and, since it's all discrete, no unobtanium ICs to worry about. I've had one of them on my bench for ten years and never had to take the cover off.It does have a bit of a small screen.If you look at the ebay sold listings, you'll see they seem to go for around £100, at least for working ones. Seems a bit high to me, but that's the market.If you do buy off of ebay, check the seller feedback and make sure you can return it. I've known several people who have bought scopes on ebay and had them die 20 minutes after powering them up. That can be very unpleasant if you're counting on your new toy to work.

author: Matrix828
author_rank: Contributor
timestamp: February 26, 2014, 09:22:03 pm
content: Quote from: PaulAm on January 27, 2014, 12:07:46 amI have a one of these scopes, got it from my work (a repair shop) as it was unneeded, it has very slight burn on the screen.Maybe OP is interested in purchasing it? Would have to pick it up (unless willing to have it delivered - its heavy).