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Hi as other have said the output is routed differently up to the first IF, then is the same. When I first did add a 45mhz parallel LC filter just after the first mixer, I got lower output on CW only. Jerry explained that, adding that filter for SSB would interact with the CW LO. Indeed it was the case. So a slight difference is fine in an unmodified unit. The problem in your unit is low output with both SSB and CW, so the problem should reside either in the local oscillator levels, the first mixer, the driver up to the antenna output. If you can at least measure the level outputs (with the probe) others should help you in detecting the problematic stage.

Il 22/dic/2018 05:25, "Rod Russell-Brown" <rodrussellbrown@...> ha scritto:

Did some more tests, built an RF probe for my DMM, did the maths to come up with the following outputs in watts at about 13volts.

	3.5	7	10	14	18	21	24	28
CW	0.9	0.6	2.8	2.2	1.3	2.6	1.0	0.6
SSB	3.6	3.9	2.6	2.4	3.5	1.8	1.1	1.0

As you can see, on some bands output is lower on CW than SSB and other bands it is the other way around.? I checked the inductors in the PA output LPFs and the windings looked about right (I didn't pull out the caps to check values).

So I remains with the problem why the radically different outputs between SSB and CW, that's aside from all the outputs being low.

Any further input valued - thanks team.

Cheers,

Rod

VK1ACE

On Thu, 20 Dec 2018 at 08:21, ajparent1/KB1GMX <kb1gmx@...> wrote:

From the last mixer to the antenna CW and SSB are same.

I've seen at least two with a wrong 40M LPF, though it was TX power amp but 80 and 20
had higher power than 40.
Seems the coils had about half the number of turns, they were likely 10M coils and the
caps were also questionable for correct value.? Rewound and recaped it then produced
normal power.

So it can be simple but not obvious.

Allison