Author Topic: help with oscilloscope model 34  (Read 9452 times)

whomeno

Re: help with oscilloscope model 34
« Reply #220 on: October 19, 2018, 04:14:12 AM »
I know i am a pain in the butt. my wife tells me that all the time! I want to thank you for taking the time working on this.
I have learned a lot, but I need to learn a lot more.
Thanks Rob
Gear as of now
Gibson 2017 Les Paul Tribute T
Marshall DSL40cr
Peavey valveking2

Rob Strand

Re: help with oscilloscope model 34
« Reply #221 on: October 19, 2018, 04:14:17 AM »
Quote
That was my thinking try and sell it for parts.
Would i need one if i try to build an amp?
You can go a long way taking DC measurements however there's some problems which are really hard to solve without a CRO.  One is oscillation.  If an amp oscillates you can see it quite clearly on the CRO.  Without a CRO you have to use a lot of guess work and tinkering; even then with dubious results.

It is possible to use a sound card but it's usually not good enough to solve oscillation problems.   The devices PRR mentioned very early in this thread are quite cheap and are probably good enough to get by.    Yet another option is second hand stuff but then you don't always come out on top.  Like your current case.
The mind often distorts without gain.

Rob Strand

Re: help with oscilloscope model 34
« Reply #222 on: October 19, 2018, 04:18:28 AM »
Quote
ok if I go the 2 transformer route would these ones be ok to use?
I wouldn't like to use those since they are only 0.15A secondaries.   The rating is a bit marginal when we consider the rectified and filtered heaters.  I think you should aim for at least 0.3A secondaries.   The original  effectively had 0.5A secondaries.
The mind often distorts without gain.

Rob Strand

Re: help with oscilloscope model 34
« Reply #223 on: October 19, 2018, 04:19:43 AM »
Quote
I know i am a pain in the butt. my wife tells me that all the time! I want to thank you for taking the time working on this.
I have learned a lot, but I need to learn a lot more.
Thanks Rob
No problem at all.  I'm happy you survived!
The mind often distorts without gain.

whomeno

Re: help with oscilloscope model 34
« Reply #224 on: October 19, 2018, 04:21:35 AM »
ok i see where i need to focus now  0.5A secondaries.
Thanks again
Rob
Gear as of now
Gibson 2017 Les Paul Tribute T
Marshall DSL40cr
Peavey valveking2