[sci.electronics] Determining externally what channel a TV is tuned to?

elmquist@nachos.SSESCO.com (Chris Elmquist) (10/27/90)

I've been day-dreaming about a method to determine what channel a TV
is tuned to by measuring RF leakage from the tuner (or IF, or something??)
Does anyone have any comments on the practicality of this?  Obviously
some TVs are better (err, worse?) leakers than others...

I don't have to know "exactly" what channel it's tuned to.. this
device would be able to make a correspondance say, between IF
frequency and "tuned channel"...  which might be different from
one make of TV to the next... it just has to determine the difference
between the channel settings.

I was thinking that a very sensitive frequency counter (with additional
hardware/software filtering...) might be able to measure this RF leakage
and make the determination...

Any other ideas how one might figure out what channel the TV
is tuned to without any kind of internal or intrusive connection?

Any comments appreciated--

-- 
Chris Elmquist, N0JCF
elmquist@nachos.SSESCO.com