[AMPS] Follow Up on the SB-220 Follow UP

[Jon Ogden]

>>My point exactly.  Likely the resistors went bad 
>
>€  Both +/- 5% suppressor resistors changed from 100 ohms to c. 400 ohms 
>because they "went bad"?   And, without showing any signs of having been 
>overheated.

Rich,

Define "overheated."  I bet that the temps most anode suppressor 
resistors are see are in excess of what the manufacturer thought they'd 
see.  I believe that yes, a failure that happens gradually over time will 
not be visibly seen.  Someone correct me if I am wrong, but aren't carbon 
comps very difficult to tell if they've been heat damaged?

Rather from my experience with oscillations, things happen rather 
violently when an amplifier takes off.  I would expect if an oscillation 
destroyed it you'd have more than 400 Ohms resistance.  I'd expect the 
resistor to be blown open like has happend to me a couple of times.

73,

Jon
KE9NA


-------------------------------------
Jon Ogden
KE9NA

http://www.qsl.net/ke9na    <--- CHECK IT OUT!  It's been updated!!!!!


"A life lived in fear is a life half lived."


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