Yes, a literal mess.
The whole house has gradually become so messy that I have trouble finding space for a guest. Yes, that kind of mess.
So now the huge project is getting it pushed out. This may take some time, but in between there are a few radio related projects I want to get started, so I started making space in the electronics' lab.
While everything else in that small room is a total (well, not total, but still..., the workbench surface is now mainly visible, and I can access some test equipment and tools. It's still a long way to order, but slightly less chaos.
Now for some projects:
Antennas.
In freezing temperatures and snow outside? No, not for me. When the weather gets warmer and better again, there is still several antenna projects, as my antenna system has been deteriorating for a while.
I am glad I got my 23cm vertical up and running in a decent way, with a preamp at the antenna. It's working well in most directions, there are still some poor directions.
A rotatable horizontal directional antenna is in the plan for better weather conditions. Some preparations are needed, so I will get there, probably in the spring.
23cm.
I can hear more stations than can hear me. I think this is due to my use of the preamp near the antenna, almost no one else around here does that with their verticals, just using an existing cable and possibly a triplexer. A quite lossy system to work with. So what do I do? Build a PA.
23cm Power Amplifier.
I got a linear amplifier built with 4 power modules. It is supposed to deliver about 50W, although I would not try that with a mode like FT8 (or other digital modes). I will need to build a coax relay system and more importantly, a sequencer, so I can avoid blowing up the preamp.
When that system is up and running, I will focus on another amplifier, running 40-50W, but for FM only.
I found a module in China, that has been used for sweeper jammers, a power amplifier covering 1200-1300MHz, with a nominal 50W output with about 10mW drive, quite some gain there. The module has no cooling, so some external cooling is mandatory.
This module requires a more elaborate sequencing procedure, as the output needs to be connected to a correct load before even applying supply voltage (28V). Initially all this will be indoors, but it could be mast mounted at a later stage. Ughh! Weather proofing needed, so maybe not ;)
QO-100 Uplink Power Amplifier.
My uplink system for the QO-100 satellite broke a while ago, the power amplifier blew at some experiments, so I need two things:
- repair the amplifier I had, if I can find the IC or transistor.
Before that I will be testing a 13cm PA module from SG Lab in Bulgaria.
This is my test setup. The mechanical part will come later.
This PA should deliver 15-20W (enough for the narrow band uplink) with a max drive of 40mW.
I intend to use my IC-905 directly on 2400MHz As this transceiver has a 2W output maximum, I will mount a 10dB attenuator, followed by a 6db attenuator at the inout of the PA, and then run the TRX at 80% output power. I don't want a power spike from the TRX to ruin the PA.
No relays are needed, as the PA has a built-in RF-VOX circuit with delay, not for the test. There is a PTT output from the IC-905, so that can be used in a permanent setup.