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What do I check when QMX transmit stops working?

 

I connected my QMX to a 20 meter QCX 50 watt amp and the result is failed QMX transmit (no power).
My QCX does OK with this amp but the QMX took a permanent dive for some reason.
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Receive is fine, but transmit is now zero.??
Transmit does draw power from the supply but offers no RF.
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Supply power to QMX is exactly 12V
Supply power to 50W amp is 20V
Each has its own regulated power supply
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Ken AA7JC
 

Have you Enabled TX PTT in PuTTy? If not here are the steps to do so.
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  1. Navigate to the QMX Menu:?Access the QMX putty menu using the appropriate method for your QMX device (e.g., using the on-board keys or a connected computer).
  2. Locate the "Transmit" Setting:?Within the menu, find the setting labeled "Transmit".
  3. Enable Transmit:?Press the "E" key to enable transmission for the selected band.?This allows you to transmit on the chosen band.
  4. Locate the "TX PTT +5V" Setting:?In the same menu, find the option labeled "TX PTT +5V".
  5. Enable PTT +5V:?Press the "E" key to enable the +5V signal on the PTT connector during transmission.?This provides the necessary signal to activate the transmitter.
  6. Verify Settings:?Double-check that both "Transmit" and "TX PTT +5V" are enabled for your desired band to ensure proper operation.?.
 

My QMX transmit is broken with or without the amp
Settings are (and were) as per your notes (transmit & 5V PTT enabled for each band).
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I have no idea why or how the amp killed the QMX since it works with other QCX radio.
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The QMX was fine in every way until I tested it with the amp.? Now it only receives.
It keys when I key it up but has zero power.
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Thanks for your reply.
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Ken AA7JC

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