Electronics ⁽²⁴⁾

Well. Further to my previous post where all hope seemed to have gone out of the window I finally made progress today, but not the way I set out to. First off, I pulled a Raspberry Pi 4 from another project and sat the CaribouLite HAT on it. Next was a fresh installation of DragonOS. But this time it did open the ssh port - I've no idea why it did not before and note I am being unscientific here as I changed the Pi, but I am not going backwards. Then, time for install.sh... All seemed to go well but the software failed to compile completely. Searching on the errors I added #include to two source files, cariboulite/software/libcariboulite/src/CaribouLiteCpp.cpp and cariboulite/software/libcariboulite/src/CaribouLite.hpp. Stripping out all the 'apt's and 'depmod' from install.sh and running it again and the software compilation completed! I had already added and commented out the necessary lines in /boot/firmware/config.txt so a reboot was all that was needed to kick it into life. The driver was loaded - lsmod|smi showed this and also /proc/device-tree/hat now exists, both precursors to success according to the notes and YouTube videos. Running sudo SoapySDRUtils --find showed the card, and, finally (!), running SoapySDRServer…

I came across this via a post someone made somewhere - actually it might have been an email on a group. Anyway, with a tx/rx range top to 6GHz I thought, why not? It arrived quite quickly from Crowd Supply via Mouser with Crowd Supply charging the VAT but no other taxes on arrival. I duly mounted it on a spare Raspberry Pi 3B with a fresh Bookworm 64 bit OS and followed the installation instructions at https://github.com/cariboulabs/cariboulite but I always got various errors and never got to a working system. The errors were mainly surrounding the SMI driver and the kernel headers. There seemed no way round this one, and thus no working system. Following on from another complaint I downloaded and installed DragonOS, a 64 bit variant with lots of SDR utilities built in. Once installed, although the developer stated that ssh is available from first boot and does not need the usual empty ssh file it is not - the system does not open port 22 but does open the vnc port so I then had to find out which of my desktop systems has a vnc viewer as I never use it. When I found one…

My second NinoTNC is built. The parts came today from Mouser in a huge box. I need to adjust the case a little to make it fit nicely but now I have this one I can go mobile and see how access to GB7RVB is. So far, no-one has connected (and yes, the antenna is still in the loft!) I did find a TNC program for the Mac called KISSet which works fine once I remembered to put my callsign in! I wondered why it was sending data and GB7RVB's TNC was receiving - no callsign. Twit. It worked fine after that.

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.

See, I built it! And it works. The 3D printed case needs a bit of tidying but is perfectly functional. All I need now is a radio to use it with plus probably re-use one of my spare Pi 3B cards to drive it.