Oscilloscope smoke so need a new one, any suggestions?

[dr pepper]

I was given a bbc master a year back, chucked it in the bin.
Bit a new 'scope is always welcome.

 

[tomizett]

I've got one that I bagged from my old school, thinking it might be fun to play with - but I don't think I ever touched it. There are an awful lot of them stil about, it seems... presumably being designed to be (ab)used by school kids they where virtually indestructible.

 

[throbscottle]

Nice to hear that people are still putting time into their favorite testgear. My father had (still has, I think) a Cossor with Nuvistors in, I believe, so they did make them. Can't tell you the model off the top of my head, I'm afraid.

1035, by any chance? I couldn't resist having a search and it's the only one that seemed likely. Got me reading about nuvistors now. Fascinating reading: http://www.r-type.org/articles/art-150.htm

 

[tomizett]

From a little google image search, I think it was a CDU110.
Thanks for the link... now I'm reading about them too!

 

[NsrMagazin]

How did you burn the previous one? Shouldn't we try repairing it or search for a new one with some defence?

 

[dr pepper]

Right then, I spent nearly 4 hours on this silly telequipment of mine, and finally got it to work.
Its not a brilliant 'scope to be honest, the display is failry dim, moan winge moan.

I replaced 3 Bc107's, a mps715, 3 electro's and a 220k resistor, all dead except the Bc107's which were reading low gain, below 100.
The 'scope now triggers all the way from 10hz to 10Mhz.
The trace amplitude varies when I turn the brightness all the way up, and the vertical pos for chan 2 is way too sensitive, more to fix.

 

[dr pepper]

Ok 2more transistors, 5 more resistors and the old telequipment now works Ok.
The size vs brightness issue was a resistor on the focus pot & another on the brightness pot causing the 1kv grids supply to vary.
Ch2 position sensitivity was a corroded earth connection between attenuator switch & chassis.
Camart your right to trash your old one, they are a lot of trouble to repair.
And I did get zapped twice, once off the 1kv rail, both times the power was off, still bloomin hurt.

 

[camerart]

How did you burn the previous one? Shouldn't we try repairing it or search for a new one with some defence?

Hi N,
Who is your question aimed at!
C.

 

[camerart]

Ok 2more transistors, 5 more resistors and the old telequipment now works Ok.
The size vs brightness issue was a resistor on the focus pot & another on the brightness pot causing the 1kv grids supply to vary.
Ch2 position sensitivity was a corroded earth connection between attenuator switch & chassis.
Camart your right to trash your old one, they are a lot of trouble to repair.
And I did get zapped twice, once off the 1kv rail, both times the power was off, still bloomin hurt.

Hi P,
My last zapping was from a camera flash capacitor, I try to minimise it as much as possible, also I try not to go up ladders, having had some near misses previously, although some bluetits were in and out of the bird box I put up earlier

In the past I've sent hours. days, weeks, taking things apart and mostly putting them back together, and I've got shelves of reclaimed stuff, waiting for 'that day'. I've now got to the stage where I let someone else do it.

Glad you got your equipment working.
C.

 

[dr pepper]

Thanks Cam.

 

[NsrMagazin]

Hi N,
Who is your question aimed at!
C.

You. It probably won't be hard to find an osciloscope in your local shops or second hand, however since I don't live in your country I can only comment on repairing the old one.

 

[MichaelaJoy]

camerart: Do you have a preference for digital or analog?

If you don't mind digital, look up Hantek DSO5072P on Amazon

A lot of bells and whistles for the price.

If you work with High Voltage, you might want to pick up a high voltage scope probe.

Otherwise, you'll have to try your luck on ebay. I got lucky and picked up a Tektronix 2465B for $300USD. It needed to be repaired, but I found a guy out of California that specializes in Tektronix. He repaired and calibrated it. That was 2 years ago and it's still going strong.
(knock on wood )

 

[camerart]

camerart: Do you have a preference for digital or analog?

If you don't mind digital, look up Hantek DSO5072P on Amazon

A lot of bells and whistles for the price.

If you work with High Voltage, you might want to pick up a high voltage scope probe.

Otherwise, you'll have to try your luck on ebay. I got lucky and picked up a Tektronix 2465B for $300USD. It needed to be repaired, but I found a guy out of California that specializes in Tektronix. He repaired and calibrated it. That was 2 years ago and it's still going strong.
(knock on wood )

Hi M,
Thanks, but look at #13
Actually, when it came the guy had enclosed a second probe, not advertised.
C

 

[MichaelaJoy]

Best of luck with the scope.