Re: freq meter vs. spectrum analyzer for sweeping
bob said:
You need a spectrum analyzer, which shows you signal strength vs. frequency.
And you need to worry about intermittent ('burst') bugs.
And WTF is an 'infinity' transmitter?
Umm, all the stuff being sold for counter surveillance are frequency counters of one sort or another. Infinity transmitter? I guess you don't know much about bugs if you don't know that -- try a web search on the term.
On Wed, Jul 11, 2001 at 08:29:02AM -0700, A. Melon wrote:
bob said:
You need a spectrum analyzer, which shows you signal strength vs. frequency.
And you need to worry about intermittent ('burst') bugs.
And WTF is an 'infinity' transmitter?
Umm, all the stuff being sold for counter surveillance are frequency counters of one sort or another. Infinity transmitter? I guess you don't know much about bugs if you don't know that -- try a web search on the term.
Amusing... And from what I can tell from the descriptions of the two types I saw, if you are looking for it with a frequency meter, grid dip oscilator, specturm analyzer, RF meters, or whatever, then you are barking up the wrong tree. Both of what I saw worked through the phone lines (one using the existing phone line and one using an additional phone line) and would not be emitting RF. Are you think of a third type that activates over the phone but transmitts on RF (Why? If it transmitts RF, why not activate it with RF and avoid the need for the telephone call in, entirely?) or were you just not thinking? I suppose that one might be led to the false conclusion that because someone put the word "transmitter" in the name that it must transmit RF. The mouthpiece of a telephone handset is also called a transmitter and doesn't emit a spec of RF. BTW... A voltmeter across tip and ring should detect the one type while the other type requires the installation of an additional phone line and wouldn't ring your phone. The former (single line) would also interfer with normal operation of the phone. Get a "call and hang-up", hang up, count to twenty, pick up, draw down a dial tone (which could, in theory be faked - classical modem callback trick) and call someone else, preferably someone with calling line ID who can verify your phone number (to avoid stupid loopthrough systems - another classic "man in the middle trick). The former also does not work well with ESS switches because it depends on "calling party disconnect" to hold the line open, which ESS will not do. The later (the two line system) was specifically advertised as working within ESS systems without requiring modification to the ESS system (obviously to work around the "called party disconnect"). From the desciptions I have seen for the "classic" ring-up single line infinity transmitter, it seems to be little more than the "classic" diode-bridge to hold a line off-hook where the calling party can still hear the called party phones after the called party hangs up. Lame... No transmitter, and you just have to install the bridge and controller anywhere on the POTS pair between the SLC and any of the phones, even outside the house on the drop line. If you have a few thousand feet of copper loop between you and the SLC, it doesn't even need to be in your subdivision. Nothing needs to be installed in the house at all to make that work. It's still lame and easy to detect (line voltage siting at off-hook voltage) and even a "busy line" detector you can get at Radio Shack (lits up to indicate when another extension is off hook) should detect it. But NOT with an RF detector. :-) Also wouldn't work with ISDN phones. As far as ring and hang up goes... We average about 2 of those per day, always from "out of area" and always tracks down to these moronic auto telemarketing boxes that overdial the number of operators. If you answer the phone and say "hello" and the autodialer doesn't have a free operator to had you off to, it hangs up the phone. Been discussions to make these illegal (since they don't give you an opportunity to tell them to add you to their "do not call list" they already violate FCC rules in theory) and to make the use of "out of area" CLID indicators by telemarketers illegal for the same reasons. I happen to know people who work for a company that designs and manufactures those devices. Some of these clowns configure them for dialing as many as 10 times as many numbers as people handling the calls. That way if you only get 1 out of 10 answering the phone, all your operators stay pretty much busy. If you get more than one out of ten answering the phone, you generate a lot of "call-and-hangup" calls. But you (the telemarketer) don't care about them because they can't identify you and they can't tell you to never call back and the extra calls don't interrupt your dinner. Mike -- Michael H. Warfield | (770) 985-6132 | mhw@WittsEnd.com (The Mad Wizard) | (678) 463-0932 | http://www.wittsend.com/mhw/ NIC whois: MHW9 | An optimist believes we live in the best of all PGP Key: 0xDF1DD471 | possible worlds. A pessimist is sure of it!
On Wed, 11 Jul 2001, A. Melon wrote:
Umm, all the stuff being sold for counter surveillance are frequency counters of one sort or another.
That's because Joe Sixpack can't even *hope* to afford a decent spectrum analyzer. My *nine year old* HP cost me just under $8,000.00 - _used_. If you are serious about sweeping, go rent one of these. Get one that covers at least up to 22ghz. -- Yours, J.A. Terranson sysadmin@mfn.org If Governments really want us to behave like civilized human beings, they should give serious consideration towards setting a better example: Ruling by force, rather than consensus; the unrestrained application of unjust laws (which the victim-populations were never allowed input on in the first place); the State policy of justice only for the rich and elected; the intentional abuse and occassionally destruction of entire populations merely to distract an already apathetic and numb electorate... This type of demogoguery must surely wipe out the fascist United States as surely as it wiped out the fascist Union of Soviet Socialist Republics. The views expressed here are mine, and NOT those of my employers, associates, or others. Besides, if it *were* the opinion of all of those people, I doubt there would be a problem to bitch about in the first place... --------------------------------------------------------------------
participants (3)
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A. Melon
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measl@mfn.org
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Michael H. Warfield