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QMX+ PA Voltage marginally low

 

Hello,
I have built up my QMX plus purchased at the Telford rally and have a question to check.
Using a PuTTY terminal to access Hardware tests, Diagnostics, under transmitter; the Voltage (on the PA) is borderline low. This is consistent across all bands.
The build is for a nominal 12V operation.?
Example for 40m operating into a dummy load. The PA voltage reads jumps between 9.7 Red and 9.8 Green, while the input voltage is read as 11.6V or 11.7V. Should I be concerned about this or is about 2V drop over the modulator considered acceptable.
Best regards Trevor G6PSZ
?
 

Hello Trevor

Marginally low PA voltage is not considered a problem. It's acceptable. There's device to device variation. In the future?I will include in the firmware a calibration function that can measure and adjust for device variations in the PA modulator.?

73 Hans G0UPL



On Wed, Sep 25, 2024 at 6:16?PM Trevor Shackleton via <trevorshackleton=[email protected]> wrote:

Hello,
I have built up my QMX plus purchased at the Telford rally and have a question to check.
Using a PuTTY terminal to access Hardware tests, Diagnostics, under transmitter; the Voltage (on the PA) is borderline low. This is consistent across all bands.
The build is for a nominal 12V operation.?
Example for 40m operating into a dummy load. The PA voltage reads jumps between 9.7 Red and 9.8 Green, while the input voltage is read as 11.6V or 11.7V. Should I be concerned about this or is about 2V drop over the modulator considered acceptable.
Best regards Trevor G6PSZ
?
 

Thank you for the verification, Hans.
I will look forward to the calibration function when time allows.
73 Trevor G6PSZ

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