Hameg 203-6 capacitor testing

[Ronners]

Hi there I have just bought a Hameg 203-6 Oscilloscope as I thought it would be handy for my new hobby old valve radio repairs and restoration. I have to admit I have never used this equipment before. My question is can anyone tell me how to set it up to identify the foil side of a capacitor? I have downloaded the manual and there are tutorials on you tube but no one shows you how to actually set it up. Can anyone help this newbie? I have had to buy new probes for this as they didn't come with it do I have to calibrate these if so how?Best regards Ron H.

[David G4EBT]

There's a forum thread here which tells you how to do it:

https://www.vintage-radio.net/forum/...d.php?t=117051

BTW, you don't need a 'scope to do the check - an amplifier will do if one is to hand.

There's also some useful notes that you can download here from the Eddystone User Group (you don't need to be a member), entitled 'Technical Shorts - The Oscilloscope in Radio Servicing' which features, in part, a Hameg 'scope and explains how to adjust the controls:

http://eddystoneusergroup.org.uk/Res...0Servicing.pdf

By the way, none of the Hameg English language manuals contain images of the PCB foils, not that you'll want to go delving inside it, but for the sake of completeness, if you want that information, you'll need to download the Spanish version of the manual. If you can't find it, I'll happily emails it to you if you send me a personal message with your e-mail address.

You'll know that your 'scope has a built-in component tester which you'll find handy. You'll see the 20 pictures in the manual of such components under test such as germanium, silicon and Zener diodes, capacitors, transistors, FETs etc.

You'll also note that your scope has a built in calibrator with 0.2V and 2V square wave output.

Be very gentle with the variable gain controls - the little red knob in the centre of each of the Volts/Div controls. Normally they need to be in the 'Cal' position, which is fully anti-clockwise. They're quite delicate and can easily be damaged if turned to hard at the end stops.

Hamegs were - in their day - the best selling 'scopes in Europe, many being used in schools, colleges and universities. As such, its as lottery whether or not they have fallen victim to rough service at the hands of successive students, or whether they were treated with respect.

Great 'scopes - ideal for hobbyists such as ourselves.

I've had a Hameg 203-7 for some years now. Not sure how it differs from the 203-6. They're both 20 MHz bandwidth, but to show how good they are, I've attached a pic of mine showing a 55.5 MHz trace from a signal generator I restored last year.

Have fun!

[Ronners]

Thanks for that David I think you have pointed me in the right direction. Best regards Ron H.

[Diabolical Artificer]

Here's a couple of "scopes for dopes" type video's - https://www.youtube.com/watch?v=8ZKMrzTGxLQ and https://www.youtube.com/watch?v=niBG...068E0&index=20 w2aew does some great video's BTW.

Regarding testing for the foil in caps you basically connect the probe across the cap and bung the scope on it's lowest setting, pinch the cap between fingers, swapping them round till you get a trace with the lowest amplitude. This then ID's the foil side by which ever lead is connected to your black ground/earth lead. It's never worked for me despite trying it on three different scopes, one with a sensitivity of 1mV/div. I damned if I could see a difference, even subbing my fingers for a mains lead.

Andy.

[Ronners]

Cheers Andy very useful information. Best regards Ron H.

[Ronners]

OK folks I have tried the amplifier test on caps but no difference either way round could it be that the new caps are well insulated so will go in either way? Best regards Ron H.

[See_Mos]

For most applications it does not matter which way a non-polarised capacitor is connected.

In some high frequency radio applications it can make a difference but there is an awful load of b******t on audiophools forums and associated component retailers sites but it really is an ounce of truth and a ton of b******t.

Axial lead capacitors have a larger surface area on the end of the wrap but those green and orange radial lead ones have very little.

I stand to be corrected but I never came across a valve amplifier or domestic radio where it made any difference which way round non-polarised capacitors are connected.

[Ronners]

Thanks for that See Mos you have cleared up another question for this newbie. Best regards Ron H.