222 MHz Transverter

gevv · Tarih: 15.12.2006, 15:15 Mesaj konusu: **222 MHz Transverter**

2 Meter Miniverter – a tiny transceiver
Paul Wade W1GHZ ©2001
Last fall I acquired a used 10-meter mobile rig, an HTX-100, with the hope of using it as
an IF radio for microwave transverters. Since most transverters have an IF output of 144
MHz or higher, an intermediate transverter was needed. It would have to be small
enough to fit inside the radio, inexpensive, and have adequate performance for
microwave operation.
Down East Microwave offers small transverters for 144 and 432 MHz for this
application. Some time ago, I tried to fit the 432 MHz version into another HTX-100, but
it didn’t quite fit, so I ended up trading the whole mess for something else.
The problem with the DEMI transverter is that it had the same LO oscillator and
multiplier circuit as their big high-performance transverter, and the LO took up most of
the space. For 144 MHz, a smaller oscillator circuit might be possible — at a flea
market, I found some canned computer oscillators for 115 MHz, perfect for a 29 MHz
output. The oscillators have the same footprint as a 14 pin DIP IC.
Printed Circuit Board
I was ready to build a dead-bug transverter on a bit of perf board when heard about an
outfit called ExpressPCB. They offer a “MiniBoard Service” —

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