This weekend I spent a few hours on Saturday getting some issues I’ve had with my Station interface project with the sound paths to the sound CODEC chips. Luckily I could solve the problems and could spend some time programming again, getting closer and closer of getting something which might be useful. However quite a lot of small mistakes made so I will need to do a hardware revision. Not only because of mistakes though but also because I’ve realized I want a few more functions.

Sunday I went to work to do some regular work (that I get paid for) but after that I didn’t really feel like going home so I stayed and thought I’d build a bit on a kit I bought some time back from http://www.communication-concepts.com/. I bought it to be used as a preamp, so we could be able to get decent output of the 4-1000A amp with 100W rigs (after BPFs etc less than 100W) but since we kind of scrapped the 4-1000A amp and is using the HV transformer in the QBL project instead I don’t really have much use for the amplifier, but why not build it anyway just for fun.

Today Tuesday I got bored sitting at home after work so I went back and continued work on the QBL tube socket and I also cut a hole for the socket in the center plate in the amp. I had some teflon lying around that I used to mill some isolator and I am quite happy with the result. Now I need to figure out a chimney. I also had a friend help me to design some gears for the stepper motor potentiometer (feedback) that I’ll get 3D printed. When I have those parts I can continue to design the holders for C1, C2 and the L with the stepper motors.

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Continued the work last week on finishing up the socket for the QBL tube and also made some holder for the inductor and modified it so that it will have its output on the same side as the C2 capacitor will be placed.

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Today I got a lot of stuff done at work. I have built a sound mixer box using two HA-400 headphone amplifiers. Pretty much works as a regular SO2R box but it’s made for two operators instead with two headphone outputs and possibility for each operator to select which sound levels they want from each radio and also if they want to listen to both radios or just one radio.

I also worked on the socket for the QBL amplifier that I got from SM3MXR, he also donated a tube in good condition. The mockup tube I am using was donated by SM3BDZ, it’s 90% OK so still good for legal limit power output. I first tried one idea which didn’t work so well, so I changed it and milled out another board which should work a lot better. The way I am doing it is inspired by SM2CEW and SM2EKM. It’s not really needed to have such screen decoupling on an HF amplifier but it was the easiest way to mount the socket, since I believe they are originally made in similar way.

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