On 05/13/20 21:21, Ed Krome via AMSAT-BB wrote:
I’m a bit surprised that so few are using portable (and no homebrew) 1267. Here’s an alternative, homebrew style. Something old and something new. Antenna: 12el hb yagi with folded dipole DE, mounted on top of Arrow with 8” fiberglass rod spacers Amplifier: hb brick amp with RA18H1213G. See AMSAT Journal Jan-Feb 2019 for construction details. Can do 30W, but never use that much. Transmit-converter: ancient hb, dbm + discreet transistor amps. Would be so much easier today with MMIC’s. ~1/2W out. Originally built for AO-10 and used a lot on -10 & -13 RF (2M) source: Baofeng UV5R+ ht. Why? Because that thing has no problem transmitting slightly below the 2M band edge. The trans-converter was crystaled so 145 in = 1269 out. AO92 is 1267.x, so the trans-conv requires 143.x input. In the AO10&13 days, the driver was a Drake T4X driving an hb 2M transverter. Complicated, but as a fixed station (100+W out from 2x7289) it worked well.
Ed-
I'm an avid home-brewer, but family, work, grad school, and volunteering has gotten in the way of me getting a real satellite station on the air.
I have a mostly-built 23cm FM rig (http://www.pe1jpd.nl/index.php/23cm_nbfm), which I bought as a first-pass attempt at getting on 23cm. Just needs to be buttoned up into a chassis and we're ready to roll.
I've also duplicated a few preamp designs (https://www.n0zgo.net/lna), and started building a SatNOGS v2 rotator using laser-cut mounting plates (https://www.n0zgo.net/satellite/satnogs/rotator_build).
Some day, I'll get this stuff done and on the air. :-)
I hope more amateurs build their own equipment. So many diagnostic aids (SDR, o-scopes, spectrum analyzers) are available for cheap compared to 20 years ago!
--- Zach N0ZGO