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Old December 8th 03, 06:25 PM
Dr. Death
 
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"Frank Gilliland" wrote in message
...
In , "Dr. Death"
wrote:

I noticed that a lot of high end auto audio systems use a capacitor in
series with the main power lead to the amplifies so the amp hits harder.
Could this same principle be applied to ssb, I think it can.
place a 1 farad audio cap inline with the power lead to say a Texas star
dx1600 and you run the rig on ssb the cap will discharge under peak load
giving you a higher average output.

Any comments? (and I mean REAL comments)



Even though you are a troll, you actually raise a good point here. Now I'm


troll????? you don't even know me.

assuming you meant that the capacitor is connected in parallel with the

power

bad on my part, i thought it was in series butv after closer investigation i
found they were grounding it with the mounting bracket

supply leads, because if it were connected in series you would get no

power.

In an SSB amp the RF power follows the audio, and will therefore have a

current
draw that varies at audio frequencies. A capacitor placed across the power

leads
of the amp, when combined with the inherent resistance of the wires from

the
battery, creates a simple low-pass filter which will help smooth out those
'audio' peaks. The bigger the amp, the bigger the cap. And keep the leads

from
the amp to the cap as short as possible.


So you agree, it would work for ssb

BTW, this type of filter won't do much in AM service since the current

drawn by
the amp in AM is fairly steady (at least it -should- be, i.e, it's not
amplifying a signal loaded with overmodulation and 'swang'). But it -will-
filter out noise from the power supply.

A word about those 'moster caps' for audio amps: Most of them have a high
equivalent series resistance (ESR) which defeats the purpose of using

them. They
behave more like a rechargeable battery than a capacitor. Locate your

local
computer junkyard and get some of those big electrolytics from the

mainframe
power supplies. Typically, just one 100,000 uFd aluminum electrolytic has

a
lower ESR than a 1.0 farad 'monster' cap. Also remember that you can

reduce the
ESR by putting capacitors in parallel. Ten 10,000 uFd caps in parallel

will have
a much better ESR, and therefore much better filtering ability, than one

100,000
uFd capacitor of the same type, even though the total mFd value is the

same.





=============

"...but I admitted I was wrong, Like a man! Something you and QRM
have a problem with. You guys are wrong and you both know it and
are both too small to admit it."
---- Twistedhed ----

=============


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