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Jim Thompson[_3_] Jim Thompson[_3_] is offline
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Default Okay, so, what am I missing here?

On Fri, 25 May 2012 09:44:12 -0500, John Fields
wrote:

On Wed, 23 May 2012 15:40:17 -0500, "Dave" wrote:

Posted a while back about a project I am trying to concoct- an intercom for
my front door- and have made some progress. Unfortunately I hit a speed
bump when I added transistor Q4. Now it only gives me noise at the output,
and lots and lots of that. Capacitors are all 100uF 35V, which I am
thinking may be the problem (maybe the last couple need to be 50 or 75V?)
Originally thought I might be overdriving Q4, so I replaced it with a 2N5296
from my junkbox, but that just doubled the volume of the noisy output. If
anyone sees something I should but don't, please post. The only thing I can
think of is upping the voltage on C8 and C9.

Any help is *greatly* appreciated...


Can you post the circuit list, please?


You're late to the game. Track thru the message-ID's. Dave is one of
Ian Field's buddies. See how he responded to my offer of help.

...Jim Thompson
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