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Emergency modulator

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After many enjoyable hours using my 80 and 40 meter c.w. rig I decided to try my luck on phone. I didn't have a modulator so I tried to think of an inexpensive way to convert to phone operation. I had an old television power transformer and an old phonograph audio amplifier with a microphone preamplifier stage. These parts connected as shown in Fig. 1 made up my new modulator.

Fig 1
Fig. 1. Circuit showing a modulator using a power transformer modulation transformer.
T1 Power transformer.

Only a few connections are required for the modification and it is an easy job to shift back to c.w. Reports on the voice quality are excellent and many successful phone contacts have been made.

David T. Saussier, jr., W3MLE.