[Milsurplus] True MCW

[holden]

Actually, the earliest MCW (or ICW for the purist) was done with a chopper wheel,
which broke the B+, or cathode connection, or grid, whatever, usually at a rate of
500 Hz or so, thus each element was a series of 0.5 to 1  millisecond-long  bursts
of RF. Choppers were used on both spark and arc, as well as early CW transmitters,
like the early RMCA ET 3600 series. Not unlike synchronous rotary gap spark. You can
also get MCW by running the oscillator on raw AC, which gives a 60 Hz note, or, if
you run push-pull, 120 Hz.  Broadband signals, but generally very pleasing to the
ear, and as previously said, no oscillating detector needed. I run a Ford model T
spark coil-powered rig in the AWA 1929 party.....about 140 Hz of VERY unsinousoidal
waveform.

//Howie WB2AWQ

Smith wrote:

> Today's aircraft navigation aids do Identify with a sort of modulated CW but the
> transmitter carrier is constant and does not go on and off with the keying of
> the tone.
> When running true modulated CW, the carrier is keyed with the audio tone
> creating a great QRM busting signal, wide yes, but unique and easy to tune in.
> Putting on the BFO and listening to it was a treat, you could hear all sorts of
> audio harmonics in the signal. I have ran it on two meters during contests and
> really stirred up an audience but the nice thing about it was you didn't get any
> dupe contacts, everyone remembered the signal. Too bad we can't run it on 40
> meters, probably wouldn't be any worse than hearing all that "buck shot" running
> up and down the band from the 11 meter troops  running  all that audio.
>
> breck k4che
> Dover, Delaware,
> annt nutten in Dover, except chickens, a NASCAR track and hams that cant solder.
> But the beach is close!
>
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