HAVE QRP RIGS, WILL TRAVEL: Inside the Radio Menagerie of VK3YE
Special to The ARS Sojourner
A QRP DOUBLE-SIDEBAND TRANSCEIVER
First is a 4-watt frequency-agile double sideband transceiver for 80 metres. NE602s are used in both the transmitter and DC receiver. An L-match ATU is mounted on the rear panel. This matches antennas such as the end-fed half wavelength wire. However, the rig in the picture is shown with a tuned feeder dipole. The transceiver is frequency-agile over a well used part of 80 metres in VK - it tunes 3.550 to 3.620 MHz. No provision is made for CW operation. It's powered by a 12-volt gel battery. The transceiver has just two knobs - ON/OFF volume and tuning. It is very small for what it does. However, the conventional front panel makes it somewhat inconvenient to use when portable.
A D-C 30 METER CW TRANSCEIVER Next is a 30 metre direct conversion CW transceiver. It started its life as a 40 meter DSB rig, but was changed to 30-meter CW. Its appearance and control layout is similar to my 40 metre DSB transceiver (described in April's edition of The ARS Sojourner). The large knob on the right part of the panel is for the L-match ATU (which has yet to be fitted). An in-built matching network saves considerable space and the need to carry a connecting cable. They are particularly good if you are only going to use the rig with one antenna - in this case you can make the inductor fixed and have only the variable capacitor variable. Small plastic dielectric capacitors are acceptable for QRP equipment. Contacts of 3,000 km have been had on this transceiver. Power output is approximately 3 watts.
THE CODAN SSB HF TRANSCEIVER Then there's a commercially-made set manufactured by Codan. It puts out 20 watts SSB on HF and has a 1.65 MHz IF. In its original form the transceiver is crystal-controlled, but the author has replaced this with a 2 MHz varicap diode controlled VFO. The set is all solid state and operates from 12 volts. Unlike most amateur gear, the speaker is included on the front panel. The set is clearly designed to be used on the ground sitting on its back panel - all controls and the antenna and headphone sockets are on the upward-facing front panel. The set is exceptionally rugged - it is possible to sit or stand on it without any problems. The Codan is designed for portable use in Australia's outback. Though heavy (it's designed to be carried in a car) the set has many TFR features. These include a compartment for the microphone, pens and paper on the left-hand side of the set, and an inbuilt antenna matching unit. No SWR meter is required - simply apply carrier and adjust the controls for maximum brightness on the set's tuning indicator light bulb. The set has a removable lid with a rubber seal to protect the front panel when it's not in use. The inside of the front panel has a list of frequencies the set has been made to operate on and a set of operating instructions suitable for the most uninitiated person. A 40-foot wire thrown over trees or bushes is suggested as a suitable antenna. The lid has a handle for hand-carrying.
A CB CONVERSION TRANSCEIVER FOR 28 MHZ Finally, there's a converted 27 MHz CB radio used on 10 metres. It is mounted by its mobile bracket in a home made box. This has a compartment for the battery, pen, microphone, etc. The antenna is a 6-foot mobile whip attached to a plastic box. The ground system is a 1/4 wavelength wire radial. Carry handles are formed from coaxial cable. The whole station can be used while carried. Pedestrian mobile contacts on 10 metres have been made with all Australian states, ZL, JA and W. The power output is approximately 12 watts PEP. A 12-volt 6AH battery was used. The station is quite heavy to carry for long hikes, but is OK for short walks. Its performance should almost equal a mobile station running similar power.
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Peter Parker, VK3YE, is a longtime QRPer, outdoorsman, builder, writer and operator living in Australia.