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From: jmn@cancun.berkeley.edu (Jan Mark Noworolski)
Newsgroups: sci.electronics
Subject: Re: Stereo Amplifier Jamming
Message-ID: <27279@pasteur.Berkeley.EDU>
Date: 28 Aug 90 20:29:42 GMT
References: <1990Aug27.215353.5186@murdoch.acc.Virginia.EDU>
Sender: news@pasteur.Berkeley.EDU
Reply-To: jmn@united.berkeley.edu (Jan Mark Noworolski)
Organization: U.C. Berkeley -- ERL
Lines: 45

In article <55577@iuvax.cs.indiana.edu> commgrp@silver.ucs.indiana.edu (BACS Data Communications Group) writes:
>dg9g@maxwell.acc.Virginia.EDU (David Guercio) writes:
>
>>I'm trying to figure out how to make an amplifier jammer, for apartment
>>use.  For instance, if someone is in the next apartment and plays the
>
>A friend says he jammed the stereo in the apartment above his, as 
>follows:
>
>He wound a few turns of heavily insulated wire around the perimeter of 
>his living-room ceiling, and connected them in series with a spark gap 
>and the secondary of a neon-sign transformer.  He says a few minutes 
>of jamming would make the neighbors turn off their offensive loud 
>stereo.  Perhaps they even made expensive and fruitless trips to the 
>repair shop.

If I'm not mistaken- all of the descriptions to date of a stereo jammer
rely on the offending party listening to the RADIO (since the jammer is
an RF source- ie. big sparks).

I have in my office a Jacob's ladder which makes a 5 inch arc- and it only 
jams our radio reception- does not affect the amplifier at all as far as 
I can tell (tapes still work fine).

I put it to you- if you jam the radio reception the offending party will
switch to cassette, LP or (worst of all!) CD (since no doubt you will be
asked to experience the high fidelity of CD sound).

It seems to me that the best way to jam the amp- is to make really bad
and nasty spikes on the power supply into it, thereby screwing up its 
voltage regulators and maybe if you're lucky :-? frying the amp. Mind you
I don't have any simple ways of doing this that I can think of.

mark 
ps. Before anyone asks and starts the Jacob's ladder thread again. To make a
Jacob's ladder go out to a sign shop, buy a used 15KV neon transformer
($10-20), attach appropriately shaped coat hangers to the HV terminals
(bottom gap about 1.5cm, top about 10?) and turn it on. Remember not to die
of electrocution. Interesting effects can be seen by throwing flour or non-
dairy creamer onto the gap (stand far back when you do this- the flames are
short but very big).
--
"It was very stupid of you to have gotten yourself lured into this trap"
						Big Boy (from Dick Tracy)
jmn@united.berkeley.edu, or jmn@power.berkeley.edu