This afternoon I have been "engineering" my dual lens optical transceiver mechanics. This consists of 2 34cm long 110mm drain pipes (with 100mm lenses at one end) fixed together on a tripod mount with a sighting scope attached to one tube and an end piece at the focal points which will support the aluminum box housing the detector, the TX LED and the electronics. I had to work out how to support the two tubes in close alignment and how to fix these and the electronics to the tripod mount. This has involved a fair bit of mechanical engineering, which is the part of the hobby I absolutely detest. By this evening I think everything is ready and fixed together OK. The electronics box has all the holes drilled for switches and sockets. Now all that remains is to build tidy versions of my sensitive detector and AM transmitter.
When everything is finished - the end is in sight now - I will ask Bernie G4HJW for a sked over a fairly short (2-3km) line-of-sight path to check alignment and that everything is OK. Assuming this goes well then it will be time to try a 481THz QSO over a reasonably DX path.
Same here. It's what I like about HF homebrewing (just about everything I want to do can be done on copper-sided board) and what puts me off getting into light beam communication. However, I do have an urge to have a go - ever since I saw a light beam communication project in a Practical Electronics (Wireless?) mag in the 70s.
ReplyDeleteA better lightbeam scheme is to use the LED as both emitter and detector as done by G8CYW. Then only one set of optics is needed. My tests with my LEDs sgowed considerable loss of sensitivity, hence why I've gone for the "2 pipe" solution.
ReplyDeleteOften think there would be a market for a "universal" QRP enclosure for HF QRP projects (with pre-drilled holes for controls and sockets and water slide transfer legends) so that people didn't have to worry about drilling.