[Milsurplus] L.O. radiation

[J. Forster]

It's an interesting idea, but I'm a bit skeptical.

First off, bias power is pretty low

Second, any acoustic noise would have to come from some sort of intended or
parasitic electro-mechanical transducer. This could be electro-striction in a
capacitor or magneto-striction in some magnetic device, or a vibration such as a
loose lamination.
I doubt it would be the hydrophones themselves because there would be amplifiers
between the hydrophones and the tape recorders and amplifiers do not usually
feed stuff from output to input (it tends to cause oscillations)

Third, I'd expect pumps, turbines, motors, and other stuff would make a lot more
noise.

Just an uneducated opinion though.

-John


Unserviceable but Repairable wrote:

> Is there any substance to the rumor that the russians DF'd American
> nuke-subs by listening for the bias oscillators on hydrophone tape
> recorders?
>
> They are in the right 30-100kc region that goes right thru H2O