VK3AQZ Powermeter

Here are a few pics from my build of the VK3AQZ RFPM1 and here is a link to Owen's (VK2OMD) blog were you can read a bit more about it.

I also made a small modification to the Powermeter, I added a external power instead of running only of battery.

Top left corner is the entry via a 7809 regulator. Need to compare low power measurements between battery and external power to see if the noise of the regulator is making the meter read different. The sensor is an AD8307 based design, so nothing special. Below measurements of the input Return Loss of Sensor 1:

Pic: 5Sensor 1 Return Loss

Sensor 1 performance: (Sensor adjusted at 50MHz / 24h @ 24°)

https://sites.google.com/site/vkonehw/home/homebrew/measuring-rf-power/vk3aqz-powermeter/red-sensor-performance_HP8656B_adjusted_at_50MHz.PNG

Signal source: HP-8656
Attenuator: HP-8494/5G