Quote:
Originally posted by mbates14
file not found error on his page.
I gots an old h-out compactron TV tube that might work.
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Again, mike, the tube is too big. The TV sweep tubes are all power tubes designed to produce several watts. In the circuit I discussed, the 6J7 is an RF/IF amp used in old radios. In this design, IIRC, it was fed the audio signal at its grid and used as a resistance-capacitance coupled pentode audio preamp to drive the grid of the 6A8 pentagrid converter tube which was operated as a modulated RF oscillator. Again with these old radio receiver RF/IF amp and converter tubes we're in the range of milliwatts with a signal that can be picked up by an AM radio at a distance of 30-50 feet. Use a sweep tube and I bet you could pick the signal up several blocks away. Again, the FCC would be calling and would probably confiscate a device you spent many hours and some cash to build. Plkate currents in these tubes run 1-2 mA or so at a B+ voltage of 120VDC (tube rectifier) or 160VDC (silicon diode rectifier).
Those sweep tubes could be put to much better use in pairs with output transformers and a preamp stage or two in a nice audio amp. A pair of those sweep tubes in pus-pull would probably push 30 watts RMS or more audio into a speaker for mono. Two pairs with two transformers for stereo.
Some old tube manuals like RCA RC15 or RC17 had a circuit for a Part-15 compliant "wireless" transmitter, IIRC.