[Milsurplus] Doubting the Foxhole Radio, conclusions

[Bill Cromwell]

On Fri, 2012-08-03 at 06:14 -0700, J. Forster wrote:
> The issue of DFing LOs was, IMO, a cannard. A crystal set could not be
> detected by any means, of course.
> 
> While it is theoretically possible that LO leakage could be detected at
> short range, it is very doubtful that it would be of any real use to the
> enemy.
> 

> 
> -John
> 

Hi John,

I believe some people may have genuinely feared that a German U-boat
might find the convoy (for example) by DFing the local oscillator in a
receiver. My experience with picking up receiver local oscillators
supports what you are saying and I also believe it was not a real issue
at all. By the time the enemy is close enough to hear your local
oscillator he already has you in sight!

I have and use the LM frequency meters. I have an awful time detecting
the local oscillators in my receivers from only a foot or two away. That
includes some regens with the detector oscillating and only *one* rf amp
for antenna isolation. If an enemy was *that* close I would not be
concerned whether he can hear my oscillator or not. And yes...what is
there for an enemy to detect from a crystal set.

Nice thing about the LM is those receivers have no trouble hearing them
(by design) so the frequency measurement can be carried out.

73,

Bill  KU8H