Ham Radio Help Desk

QRPKits.com has introduced the next model of their famous DC-xx series, the DX-xxB where xx = 20, 30 or 40 meters.

These are single frequency QRP units that are easy to build and fun.

The QRPeanut Can transceiver featured on HamHelpDesk uses a DC-40A unit.

This easy to build QRP transceiver is a single channel direct conversion crystal controlled assembly available for use with CW.

All you need to add is antenna, keyer, headphones and power. An antenna matcher makes good sense too.

Improvements include:
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In a previous post we debunked the 2 meter 5/4 wave antenna as actually an end-fed full-wave antenna resulting in a poor radiation pattern hardly optimal for terrestrial use. The fix was to turn it into a collinear with the addition of a 180 degree phased stub between the two half-wave sections.

Thus, the 2 meter 5/4 wave antenna is bunk… or is it?
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Many makers of J-poles for 2 meters claim they can also be used at 70 cm.

It may not be intuitive at first, but the answer, at least from an antenna pattern standpoint, seems to offer some hope.
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A friend of mine is preparing for the upcoming Virginia QSO Party in March 2009. Part of the preparations include a focus on some good VHF antennas to support the heavy use of VHF mobile operations in this party. Vertical polarization is key to success. He spoke of a 5/4 Wave Antenna.

Unfortunately, one web site promoting a 5/4 wave antenna solution failed to realize you can’t make an antenna longer without eventually hitting a limit.
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An airplane mechanic friend, who also happens to own a 35 year old single engine Cessna airplane, was working on his tail light when he saw broken and aging components in his tail mounted navigation antenna. While working to fix the problems he discovered an interesting balun technique.
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