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Here is a quick-switch antenna patch box, with built-in transmatch and dummy toad.

Douglas S. Byrne G3KP0 Jersey House, Eye, Peterborough, England

Put 'Em All In One Box o you already have half a dozen different transmitters., a like number of antennas, plus a transmatch, dummy-load and rf-am meter?

OK, OK, but how do you connect up this lot, eh? My bet is with odd lengths of coax, alligator clips, or even, like me, by twisting together odd bits of flex, kept in the sockets with matchsticks . . . right the first time?

Of course this is all in the true amateur spirit, but is really the quickest way to get the wires crossed - literally — and maybe sustain a nasty rf burn (and don't they take a long while to heal up? ). And it can be just as painful to the pocket when you inadvertently put things to the "smoke test" . . . such very expensive smoke!

All such dangers can be eliminated by knocking together this nifty little unit which combines a switched antenna patchbox, transmatch, dummy-load, and rf-ammeier.

You'll wonder how you ever did without it when you find you can instantaneously switch any of your transmitters to the dummy load or any antenna. And switch so quickly that a irue comparison can be made between different antennas - both on reception and transmission. Valuable time is also saved in contest working.

It will be noted at once that this unit embodies only the best ergosonic principles! The various inputs from the transmitters are on the left hand side, right next to the switches so as to keep the leads short. The meter is in the center, the tuning knob is on the right, and output sockets to various antennas are on the right hand side of the cabinet. To keep them cool, the dummy-loads are on top (actually, there's no room inside), while the liigh-Z output for the

Fig. 1. inputs irom the various station transmitters enter on the left and are sv/itciieci either straight-through !o loiv-Z antea.n£, or alternately to the dummy-load, resistance, a load-bulb, or the transmatch "rotary-roller" tuner feeding tiie long-vAre an tenna,

end-fed iongwire is way behind the capacitor, where it is more or less safe from straying fingers.

The basic requirement of this particular magic box is the Coil Aerial Tuning No. 2A for the Canadian Marconi No. 52 transmitter, currently available on the surplus market. This consists of a massive "rotary

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