[Milsurplus] Re: Mixing FM and AM (was wobulator lore)

[Marty Reynolds]

It was earlier written:

>>
>> I gather from the discussion that FM'ing an AM transmission poses no
>> problem.
>>

The Motorola FM stereo scheme did this.  Right - Left 500hz & up to
minimize deviation.  Usual sum-difference channel separation on rx.
Worked like a ring in a bell

Here's another one.

"The agency" walked into WSB 50kw AM in spring '61.  They
substituted a telephone-interfaced box for the 750kc xtal.

Engineering @ WSB quickly deduced they were doing narrow-shift
FSK beneath the regular programming.

Purpose later was surmised as stealth TTY for, the Cuba adventure.
WSB Atlanta had a thunderous signal in Carribean.

A week after the flop, out came the xtal-substitute box

All this fm WSB's chief engr.

Hey I've a wobulator-based Knight sig gen too

   Marty aka aa4rm