. QST . iver and power supplyon the right. output of 17 watts soems quiteconservative and is readily de-veloped. Modulation is supplied l)y a pairof 6AQ5s, driven l)y a 12AT7. AType Fl carbon button micro-phone is used, and there is provi-sion for either push-to-talk ortoggle-switch control of the send-receive operation. A small amountof output is coupled off at the antenna con-nection to an voltmeter to provide for tuningup. Indication of transmitter tuning is shown ona meter, which doubles as a tuning meter forreception, and in addition there is a red jewellight that indicates both
. QST . iver and power supplyon the right. output of 17 watts soems quiteconservative and is readily de-veloped. Modulation is supplied l)y a pairof 6AQ5s, driven l)y a 12AT7. AType Fl carbon button micro-phone is used, and there is provi-sion for either push-to-talk ortoggle-switch control of the send-receive operation. A small amountof output is coupled off at the antenna con-nection to an voltmeter to provide for tuningup. Indication of transmitter tuning is shown ona meter, which doubles as a tuning meter forreception, and in addition there is a red jewellight that indicates both output and circuit used for these purposes is re])roducedin Fig. 2. Tuning & Adjustment In keeping with its intended servicr, theCD-2 is designed so that a mini-mum of adjustment is recjuiredin normal operation. Alignmentadjustments of both transmitterand receiver are preset, and shouldnot require adjustment except incase of parts failure or other dam-age. In the case of the receiver,. the operator merely turns the calibrated dial, andadjusts the audio level to suit conditions. downward swing of the meter indicatesproper tuning of a signal. The transmitter has provision for eight crystal-controlled channels, selection being made witha single front^panel switch. The only tuningadjustments are the final plate tank and theantenna series-tuning capacitors. A front-panelcalibrate switch applies screen voltage tothe iT\st;il osrillntor. when the station is in the Bottom view of the Sonartransmitter-receiver. Receiverand power supply occupy thelarge section.
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License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectradio, bookyear1915
