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JD,
Thank you for the insight. I appreciate the response.
I agree with your comment that there may some kind of fault past the
L305
transformer. I have looked for broken traces in the path through to
the
ant1 connector. Finding a faulty relay may be difficult but I think
each
of the band paths are working since all of the receive bands are
working.
But I may not be understanding it correctly.

I have tried to limit transmit time where the current is high. I did
mention in a previous comment that the modulated supply current is
lowest
at 160M and highest at 50M.

I look forward to your evaluation of the circuit.

Thanks
Tommy KF4RWG


On Tue, Jan 28, 2025 at 3:47?PM J.D. Barron via groups.io
<jeter.d.barron=
[email protected]> wrote:

Tommy, Pay careful attention to what I am saying here.
If you key the radio RTTY, AM, FM, CW and you are drawing 20 amps AND

if

you key the mike on SSB and you draw just a couple of amps you are
producing RF power.
Your radio is drawing power trying to get the feed back from the

forward

power measurement circuit to satisfy the CPU power demand signal and
increasing the drive to the point where the IC current limit is

limiting

the drive to limit the current draw to 20 amps.
If the radio in SSB is just drawing a few amps in SSB with no audio

input

the current limit is not reached because the PA is just sitting there

at

idle current.
You do have something keeping the RF power from getting as far as the
forward power sensing circuit and out of the antenna jack, perhaps a

broken

trace, bad relay or a band pass filter out of kilter.
While I think that the transformer could be bad, I suspect that it is

not

as they are pretty rugged.
It has been a while since I have had an IC-7000 on my bench, but I

have

seen this kind of action from a number of radios and often it has

been in

the transmitter bandpass filters and either relay drivers or PIN

diodes

defective.
I will take time to revisit the prints for the IC-7000 and see if I

can

offer some suggestions, but if I were you I think that I would start
checking the direct pathways through the circuits after the PA

amplifiers.

The output transformer is at least carrying current to the PA from

the 13.8

volts and probably the secondary is doing it's job as well. There

could be

some shorted caps (or open for that matter) that are an issue or

perhaps

one of the TR relays etc.
Just my opinion, but I have managed to be wrong before and I reserve

that

option as well.

JD
KE4MD