2 Mar 2014

Ultra-simple 50MHz rigs and a spectrum analyser

Some years ago G6ALB and I did some tests with a QRP handheld 49MHz rig re-crystalled for 50MHz. As I recall we had a QSO over about 3km.

Here is a schematic of a typical 3 transistor QRP AM transceiver for 49MHz that would easily work on 50MHz. Because the RX has a super-regen detector and no isolating  RF amp, QRM could be caused to nearby weak signal band users, so any tests done should consider this. Simply replace the crystal and re-peak the tuned circuits to 50MHz. I have a couple of such rigs and should retune them into the 6m band. This schematic is from the YO3DAC/VA3IUL site at www.qsl.net/va3iul .
49MHz 3 transistor transceiver - suitable for 50MHz conversion
Also on the same site is a neat 0-100MHz spectrum analyser. See http://www.qsl.net/va3iul/SA/spectrum_an.html

1 comment:

Tim said...

Funnily enough, Roger - I was musing about 50Mhz AM at the weekend too. I wonder if there is any European activity. I bet it would be a lot of fun in the Es season.

73, Tim G4VXE