Hi
planning to build a VFO for a boatanchor VLF receiver covering 50-140KHz,
first IF is 169kHz and it was originally using xtal control. The VFO must
cover 220-310kHz.
The variation needs to 85kHz, and it seems easier to make a VFO above 1MHz,
possibly Clapp oscillator (my favourite since everybody else disregard it!),
might also try the Seiler.
I thought of using a 2457.6MHz xtal and mix with VFO (ca 2MHz), and divide the
output
by two or more. Suppose I could use an FF, preferably CD4013 for the mixer.
But I can't find any reference to similar constructions, only have a vague
memory that it has been mentioned in TT some time in the last 35 years
Wonder if somebody else have some experience in this, and will the mixer divide
or just mix?
960kHz resonators are also readily available, but they won't pull much.
73
Jan-Martin
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J M Nøding, Datakvalitet, TTS, Kristiansand
Telefon 0047-380-52660, 9077-7126 (QTH: 0047-380-87178)
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