Workshop weirdness

M0RVB

I have a Tait TM8110 VHF transceiver that is destined for use on packet radio. This was sold as untested but appears to work fine. However, in testing I was concerned that the bench PSU I connected it to showed a current draw of 0A. The radio was making noise and, connected to the Bird and a dummy load was generating RF. Anyway, I programmed it with the various packet frequencies, power settings and ensured the bandwidth was 12.5kHz and tried it on air. It was working fine on both tx and rx. But still 0A draw. Hmmm.

I have two identical bench supplies, Lavolta BPS-305, 30V 5A units. One has a noisy fan so I use the other. I swapped to the noisy one and it shows reasonable current draws for rx and tx. And then the noisy fan decided not be noisy any more (still working though!) so perhaps the noise from this PSU was just it sulking from being ignored.

You should also read:

M0RVB

Workshop ramblings

Been rearranging the workshop today because I ended up spreading stuff about rather illogically. I also wanted to add some boards to the roof joists to stop leaves blowing in - the eaves are open and the shed is not insulated. It's surprising how difficult it is to manoeuvre and fit an 8'x4' foot plywood sheet into an 8'2" x 4'6" space on your own! Anyway, the aim of todays mudding was to prepare for getting all the components and bits and bobs over to one side and to extend the 'projects waiting to be started' shelf which was full! All the woodwork is done now and just needs some shelves and boxing to sort out. Oh yes and there is still the matter of running some SWA Cat6 cable out from the garage which involves lifting flags, digging a trench and other adventures. This work is partly in preparation for Project QO100 as well as the model railway which will go where the components are now. Any heavy work is now all at one end and all electronics and servicing type stuff at the other, roughly 50/50. Pics will follow once I can actually see the benches and it…

Continue reading...