Seems odd. I'd first check your meter and make sure it is correct, and that
you're not facing a problem with the measurement tool.
After that... odd. I'd wonder if it was a coupling capacitor problem, like a
100nF cap has decided to crack and become much smaller in value. Been a while
but I recall the TX signal to the PA is on an RCA. I think you can pull that,
terminate into 50ohm, and see if you are getting a nice flat consistent power
level as you go up/down bands. I have a problem child Omni on the bench and I
want to say I measured 136mW at full tilt--but I did not check from band to
band.
This might help debug to if the problem is before the PA or in the PA and/or
LPF's. How it would be in the LPF's I don't know...
Lastly (or firstly) maybe poke around and see if anyone tacked in anything
special. Who knows, maybe someone put in an AM BC filter, and it's not
correct. Or there is a tap going somewhere, or something obviously not
connected correctly. Just to rule out mods that were not helpful.
Shawn kb1ckt skcc 24824
On Friday, October 29, 2021, 12:42:10 PM EDT, Scott Sheppard
<scott.vy1co@gmail.com> wrote:
Hi folks
I seen yo recall this issue having been discussed some time ago but cant
recall.
In the omni I am presently playing with from last season, is working well
except for low power out in general, and uneven at that:
160 38w
80 44w
40 38w
30 28w
20 16w
17 50w
15 45w
10 60w
A bit counter to what I would have expected as you go up in freq, generally.
Trust everyone is well,
Scott vy1co
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