10 GHz progress - March 2024
Mar 28, 2024
After several failed attempts I managed to copy GB3SEE on 10368.850 MHz earlier this week with the dish and 10 GHz modules set-up on the front patio. The beacon is only around 8km from my QTH and was a good signal when I used the dish with a Bullseye LNB and SDR back in February. I’ve since found out that the beacon had been turned off for a while which would explain why I couldn’t copy anything a couple of weeks ago!
I used a single stage LNA from a modified “Franco Board” in front of the W1GHZ transverter as there wasn’t enough gain to copy the beacon on it’s own, especially with the dish only 1.5m above ground and over an obstructed path. The beacon is perfectly readable but just shows a weak trace on the IC-705.
Now that all the RF modules have been tested successfully I’ve mounted them on an aluminium base plate along with the power supply modules, Arduino sequencer and 4 channel relay board. There’s also some future proofing, for example a 12V to 24V dc up-converter to power a waveguide relay. The base plate can be attached to the feed arm or located behind the dish. The LNA, transmit amplifier and transmit/receive relay will be mounted directly at the feedhorn.
I’ve also built a simple 10 GHz signal source using an Arduino Nano and Si5351a clock generator board as described by Bob, KA1GT. This generates a signal at 211.6 MHz and the 49th harmonic is detectable just below 10368 MHz (should be 10368.4 MHz). Better frequency accuracy could be achieved with a suitable reference and I may add this later.
Over the next few weeks I want to complete the feedhorn/dish alignment and try some sun noise measurements.