The Ecology of the Oscillator Transmitter

  
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An oscillator-only transmitter sounds like the simplest possible means of getting on the radio air ”until you consider the challenges it presents as part of the system that is a transmitting and receiving station: The problem of an adequate crystal-controlled transmitter for the newcomer who wishes to come on the air for the first time on c. w. ha
The Ecology of the Oscillator Transmitter - schematic

s never been very effectively solved for the amateur who has but a small amount of capital to invest in the first rig. The majority of the beginners now coming on the air use some type of a keyed crystal oscillator coupled directly to the antenna system. We all well know the results of this kind of operation. If the crystal is anything but the very best and most active type, the arrangement is capable of almost no usable power output. If the crystal happens to be an especially active one, it will be possible to obtain a respectable amount of power output but bad keying chirps are likely to be present, dots are very often not present if rapid keying is used, or the rig may frequently become temperamental after having lain idle for a few hours or days and refuse to key at all until it is retuned. Then, if the crystal does operate well and key cleanly, there is always the temptation to raise the plate voltage to increase the power output. This may be fine until the antenna accidently or intentionally becomes uncoupled some fine day with the result that we will usually be in the immediate market for another crystal "as close as possible to the frequency of the last one. " ”Jack Rothman, W6KFQ, "The Newcomer`s Special, " Radio, October 1938, pages 38 40 and 66. The usual beginner`s transmitter is built around a single tube, following the premise that more than one stage will make the first step too complicated or too expensive....



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