Here is a bit of background story: It was 1982 and Fred was studying for his junior year finals at Northeastern. He lived in an old apartment building on the Fens...so close to Fenway Park he could open the window and hear Red Sox games. It was roasting hot outside and he had no air conditioner. The kitchen window opened onto a central courtyard, and that's where he liked to sit and study.
Right during finals week, a neighbor started playing her stereo at mind-blowing volume...and it stayed on. And stayed on. All night, all the next morning. He finally yelled out the window and she turned it down long enough to screech a few choice words back at him before turning the volume back up to explosion levels.
He headed to campus to get some peace and was struck with a wonderfully devious idea. Off to the engineering lab...where he built the circuit described below and put it to work until, in a fit of rage, the woman threw open her window and catapulted the whole stereo out to smash into smithereens in the courtyard!
Make a simple 9V battery powered transistor, capacitor, adjustable
resistor and inductor oscillator circuit.
The simple circuit is made with parts selected for FM-Band (88-107 MHz) tuning
capability and a one meter length of wire as an antenna for the RF trans-
mission. Sit in the kitchen and dangle the antenna out of the window.
Finally, a small screwdriver allows the "tuning" of the FM-Band Oscillator's
adjustable resistor, tune until there is silence as the "victim" attempts to tune in another station. Then turn the screwdriver again and knock out her new station. Eventually, stereo destruction....Coup De Gras !!!
I want to build a spark gap transmitter similar to the Radio Shack version. (relay, transformer coil, antenna coil, antenna, 9V battery, and switch)
If you can, e-mail the info to: email@example.com
BTW, for the subwoofers, you could build a near field transmitter with
a low freq sound generator
chips, some piece of long
coils and a ferrite rod!.
You may not be able to get
a good lambda/4 antenna,
but generous amount of coil
on your side windows should
do the trick. After all now that they have proved
tesla's wireless power transmission.
I used a similar technique
on my neighbor, that was
showing off a FM reception
of a live cricket match.
I just removed the noise suppressor capacitor from a
bimetallic gas filled fluorescent starter, and then hooked it up to a 10W bulb, to keep the arcing for a longer duration. With the powerline coupling the RFI it was a total blackout!(it was done in India).
Well, yea. But. Just think of the activity as a welcome form of "civil disobedience". Besides, the legality here is decided by the FCC, who can't bother to keep astounding obscenity off the air or cables, but want to regulate the Internet. Give them something to chase. And turn your jammer on and off at irregular intervals.
In college, the campus radio station went off the air at midnight. At that time, they would rebroadcast a received feed from WMMR at the University of Pennsylvania down in Philly, about 60 miles away. Their reception antenna was on the top of the University Center.
One of the brothers realized how weak a signal they were receiving, and one Sunday morning about 3am he drove down the campus and from a hand FM mic wired to a tape deck, overrode WMMR and broadcast his own program from his VW parked just outside the center.
But it didn't stop there. Back at the frat, he had a 10 element Radio Shack FM beam antenna aimed at Philly. He swung it around to point at the UC and found he could easily override the weak signal from WMMR when he tapped in to the antenna with his FM wireless mic.
Needless to say, there were quite a few Saturday nights where WMMR was not heard, but instead a very risque program called the Catamites Corner replaced it...
(At the time, catamite was accepted in a lot of circles to mean any male slave purchased by wealthy Greek women for sexual perversions, NOT just the Olympian definition...)
Although, or perhaps because, we were working in an electronics development lab at the time, a friend of mine back in the '50s opted to use low-tech retaliation. Well as domestic tape recorders were in their infancy then I suppose part of it could be regarded as high tech. His scheme was to suspend a length of steel pipe, hit it with a hammer, record the effect on an endless loop of tape, set it to full volume in an open window facing the offenders position and go out for several hours. It was totaly effective.
I did the same thing in the early 80's when I was an RF Technician. The company's sig gen was DC to 1 GHz. I put a metal scribe in the output for the antenna and tuned it to the hard-rock frequency that coworkers loved.
As I increased amplitude the stereo volume would decrease. As the coworker increased the volume control I increased the sig gen amplitude until maximum was reached. Then I turned off the sig gen and the stereo blasted. This bothered the supervisor who made the coworker find a different station.
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