[AMPS] Technical Question #1

[Tom Rauch]

> Date:          Thu, 21 May 1998 10:04:11 -0500
> From:          Jon Ogden <jono@webspun.com>

> Tom:  Did you say that you have seen parasitic oscillation damage of 
> *ANY* kind in SB-220s?

Yes. I certainly did say I saw what I thought was parasitic damage. I 
was very clear in staing it was from what I beleived could have been 
low frequency osscillations.
  
> The reason is that while Tom may have never seen *VHF* oscillation 
> damage, he may have seen damage due to oscillations at *HF*.  HF 
> parasitic oscillations can occur in an amp that is not properly 
> neutralized.  Especially the two tube variety.

> So Tom, please clarify for all of us what you told Rich.

I specifically told Rich that there were cases where the chokes and 
capacitors on the grids looked like they were exposed to high 
voltages. Many of those cases were in amps with long leads and poor 
solder connections, and loose hardware. 

I told Rich I found several SB-220's I could make oscillate at lower 
frequencies, with proper external loads. 

Jon, this stuff is a silly waste of time. Can't we quit the kid 
stuff and stick to technical issues? I have no time for "he said-you 
said games".

73, Tom W8JI
w8ji.tom@MCIONE.com

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