[AMRadio] Numbers Stations - NPRs slant

Robert M. Bratcher Jr. bratcher at pdq.net
Sat Nov 13 21:30:44 EST 2004

At 10:54 AM 11/13/2004, you wrote:
>I was never in on the busy signal thing, but I did do something 
>similar.  Telephone numbers that had the suffix beginning with 99 were 
>designated as "official" numbers for internal phone company use.  As I 
>recall, you could dial xxx-9929 and have a friend dial xxx-9930, and the 
>two of you could hold a conversation.

Thats known as a loop. Lots of them out there but most are muted so you 
can't talk on them. Other prefix exchanges worked too.
The other fun thing is to find a bridge which is a bunch of numbers toed 
together so several people could be on at once.
I used to be a phone phreak in my younger days back when the blue box (for 
free long distance called) used to work.


The coin sounds in a payphone is called a red box. Doesn't work on COCOT 
(customer owned) payphones because the dialtone you hear is not from Ma 
Bell's line but generated by the phone. 

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