On Tuesday, October 6, 2015 at 8:18:57 PM UTC-5, DerbyDad03 wrote:
On Tuesday, October 6, 2015 at 8:53:49 PM UTC-4, danny burstein wrote:
In "Kenny" writes:

TV remotes use infra-red so can't work through walls!

A decade or two ago tehre were reports of the (then) new
compact fluorescents strobbing in a way that would sometimes
spoof infra red remote controls.


When I was a kid we had a TV with one of the original "clacker" remotes. There were 2 big
buttons on the remote. One "rotated" through power/volume: ON - Low - Medium - High - OFF -
ON - Low - Medium - High - OFF - etc.

The other controlled a motor that physically rotated the channel knob in one direction.

When you pressed a button a spring loaded hammer would hit a metal bar inside the remote
and the vibration would emit a frequency that would control the TV.

We discovered that my father's keys could be used to change the channel just by shaking them
In front of the TV. The vacuum cleaner would turn it On and Off and change the volume.

I have an ultrasonic leak detector that has a jack for earphones. The detector converts the high frequency sound into a lower range so it can be detected by the human ear. When I shook my keyring full of keys, it drove my dog nuts. I shook the keys in front of my ultrasonic detector, in my earphones, it sounded like the big chimes you hear played in an orchestra. What can be heard with the detector is amazing. ^_^

http://www.amazon.com/gp/product/B002OOWKRG

[8~{} Uncle Leaky Monster