Hello Karl,
I am having similar performance running on a 12volt LiIon battery, Raspberry Pi 4, it is built for 12 volts, and version 1_01a (have not yet done the most recent upgrade).? Because of issues with the transmitter, I do not have IC5 nor the 4 BS170 MOSFETs installed.? I am waiting for replacement parts.
In another thread, there is a discussion on CAT control that I asked about the Audio Gain setting in the configuration option of the terminal application in the QDX.? The section of the manual starts on page 82 or thereabouts depending on revision.
The thread is:
/g/QRPLabs/message/74336With all of the above, I had to adjust the Audio Gain to 80000 to get it into a range around 47 DB.? This was after making sure the mic input setting was close to the maximum (95 out of 100) in the Raspian OS.
In the future, Hans has requested that requests for help include the following information (copied from message #74319):
- What?OS you are running, including what version of MS Windows, or what flavor of Linux. Remember?that Linux, Mac and MS Windows 10 users do not need any driver installs, but earlier MS Windows users will need to install a Virtual COM Port driver as described in the QDX manual.?
- What QDX firmware version you are running; preferably if you have any issue, it would be best to make sure you are using the latest firmware at??and see if the problem persists.?
- Whether you built the QDX for 12V operation (output transformer 3:2) or for 9V operation (output transformer 3:3).
- What power supply you are using: voltage, current capability, and whether it is? a Linear or Switched Mode type.
- Now everyone has Rev 1 PCBs, but in future when Rev 2 comes along, please also state what PCB revision you have.?
- Also state any deviations you intentionally made from the manual. We may need to know about your deviations? :-/?
Have fun with your QDX!
73
Evan
AC9TU
