Real QRP!
My 136 kHz driver is an old IC 720 frigged to tx on all freqs; (usually not
simultaneously!). It drives into two 7490's arranged as a
divide-by-a-hundred so that I can put it on 13.6......... MHz and get
out 136...... kHz. This then drives the rest of the Tx. Yesterday I
accidentally fed my 136 antenna with the output of the divider instead of
that from the PA (mixed-up cables!) and I was surprised to see it appear on
MB7LF as a perfectly readable signal. Usual 74... series maximum power
per gate is 10 mW and my ant setup appears to have an efficiency of
0.1% so radiated power maybe 10 microwatts. MB7LF is 17 kms from me!
Walter G3JKV.
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