Well,
I've received the PA for the 13cm masthead project and added it to the box with a heatsync and suitable input attenuation:
I haven't stuck it down in the photo hence its a bit wonky.
The documentation with the PA suggests that about 5.1V on the monitor pin is close to PA saturation so I have adjusted my input attenuator to give just over 5V from the PA monitor port with CW key down.
With the output connected via these two attenuators:
to my XL Microwave power meter I am reading -2 dbM so that's about 38 dBm or 6.3 watts - it should be closer to 10 Watts.
To check the value of the attenuator at 2320 MHz, I used the spectrum analyser and tracking generator I made back here in zero span at 2320 MHz, and compared the signal with and without the attenuators, I measure a signal of+ 10.4 dBm without the attenuator and -29.2 dBm with. So that makes the attenuator 39.7 dB - so pretty much on the money.
Local conditions.
**UPDATE**
I kept finding my TX/RX switching was going into some kind of oscillation on RX. The unit would rapidly switch between TX and RX until I pulled the power. Oddly (and still somewhat a mystery) this only happened when the +ve voltage to the VLNA was connected to the sequencer. No VLNA power, all fine, attach VLNA power, TX/RX oscillation.
There is a VOX feature in the transverter that switches to TRX on detection of RF on the input; changing that to have a long detection time (a jumper on the transverter board) has cured the problem.
I have no idea either.
As SG labs don't seem to link the transverter datasheet on their site anymore, it's included here for reference.
I've received the PA for the 13cm masthead project and added it to the box with a heatsync and suitable input attenuation:
I haven't stuck it down in the photo hence its a bit wonky.
The documentation with the PA suggests that about 5.1V on the monitor pin is close to PA saturation so I have adjusted my input attenuator to give just over 5V from the PA monitor port with CW key down.
With the output connected via these two attenuators:
to my XL Microwave power meter I am reading -2 dbM so that's about 38 dBm or 6.3 watts - it should be closer to 10 Watts.
To check the value of the attenuator at 2320 MHz, I used the spectrum analyser and tracking generator I made back here in zero span at 2320 MHz, and compared the signal with and without the attenuators, I measure a signal of
Local conditions.
**UPDATE**
I kept finding my TX/RX switching was going into some kind of oscillation on RX. The unit would rapidly switch between TX and RX until I pulled the power. Oddly (and still somewhat a mystery) this only happened when the +ve voltage to the VLNA was connected to the sequencer. No VLNA power, all fine, attach VLNA power, TX/RX oscillation.
There is a VOX feature in the transverter that switches to TRX on detection of RF on the input; changing that to have a long detection time (a jumper on the transverter board) has cured the problem.
I have no idea either.
As SG labs don't seem to link the transverter datasheet on their site anymore, it's included here for reference.
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