Question for JT users and WSJT-x

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  • Updated 4 years ago
For users of WSJT-x.
I asked this on the JT reflector but never got an answer.

On the right side of WSJT-x, there is a vertical slider labeled "Pwr"
While advancing this slider does result in more signal output, I do not believe it's actually raising RF Power.
I control the Power Output by adjusting the "RF Power" slider in SSDR.

I 'think'......the the "Pwr" vertical slider in WSJT-x actually is like advancing Audio Output Gain in conventional radios. Just Audio Drive.

In essence, over driving the signal.

Anybody have the definitive answer on this?

Pse and tu.

Spent NY eve on 160 and 80 JT, and actually picked up two new digital band modes...and a headache.

HNY and tnx in advance.
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Bill-W9OL

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  • curious and clueless!

Posted 4 years ago

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W5XZ - dan

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Happy New Year, Bill.  I'm certainly no expert, but do mess around w JT65 / JT9 on 160m with WSJT-x, ver 1.3, r3673.  Seems to me, the power slider in WSJT-x can be left wide open; you can keep from over driving by adjusting DAX TX gain and watching the ALC meter.  Then, you can adjust power out with the flex RF power slider...works for me anyway.  73, w5xz, dan
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Bill-W9OL

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I'm reluctant to push the Pwr meter in WSJT all the way up.
I've experimented and that also effects the 'Level' meter in SSDR.
maybe I'm old school but I learned or was told, never push any setting to max.
Plus...the Flex SSDR meter turns to RED, and as an old Firefighter...but anything glowing bright red can be bad!

AS JT is a digital audio mode, I still think it's some sort of audio drive.
(Edited)
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N7AIG

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The little slider on the right of the WSJT-X control panel is, indeed, an AF gain control. By setting it to max, and then adjusting the audio gain chain following that to produce a non-clipping drive signal to the transmitter, you then gain the ability to run QRPP by lowering the WSJT-X power level. Some of us like to see just how far we can push this mode down below 30 dBm.

73 de Dave, N7AIG

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Bill-W9OL

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Thank you Dave. I was pretty sure that is was AF Gain.
So use it like we did in the old days. But just not too much. LOL
I'm 160 meter antenna room deprived, But I've picked up 2 new 160 countries so far this month.
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George Molnar, KF2T, Elmer

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Hi Bill - heard you calling on 160 last night. Good -13/-14 signals here into Vegas. Alas, you couldn't hear me! 
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Bill-W9OL

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Thanks for the note George
I usually give 160 a run 01:00Z to 03:00z
Pretty tired today, Trying to fix a old house electrical wire-ing problem today.
Just showered and my old bones are feeling the pain....
But I will probably have the rig on...and maybe I can hear you through my snoring.

I live in an urban area...and while I have Xmas lights....they make a lot of noise.
Cheap BY versions...

I've worked 75 countries on 160 mixed modes but only 62 confirmed.

When the builder built the two homes, one on each side of me. He put down sod in both the front and back yards.
That night it was easy to roll up a couple lines and lay cheap copper wire down and then relay the sod.

One day he was planting a small tree and saw the wire. Asked me if I knew what it was.
"Nah not sure, I do know they had a pile of rubbish there before laying the sod"
"Maybe that just wasn't picked up?"

Hope he doesn't read this.......
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N7AIG

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Now that's a real hoot! I finally got things quiet enough to RX 160m but I have never operated there myself. What countries did you pick up?

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Bill-W9OL

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TG9 and ...duh have to search the log as I forgot what the other one was