Does this sort of distortion occur if I run the rig at a moderately
low power output, and let a linear amp make up the difference?
In other words, if I keep the rig running real easy and clean, will
the amp, itself, add an undue amount of distortion? I thought
that would allow the amp to run kinda easy also.
Interesting thread.
=============================== K8JHR ====================
On 7/1/2010 9:39 AM, Dr. Gerald N. Johnson wrote:
Part of the reason for running low power with the digital modes is
intermod distortion that causes increased bandwidth, and part is the
available power dissipation of the radio. I have confidence the PA
transistors in the Omni V have plenty of heat dissipation but the radio
may not have quite enough. Thing to watch in RTTY (not so critical on
intermod as PSK31) is the temperature rise of the heat sink. I'd look
for a high volume muffin fan and fabricate mounts to blow air on the
case heatsink. Optimally it would be controlled by a temperature sensor
on near the PA transistors.
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