After reading many postings on the newsgroup on UK red boxing I will now clarify the issue. None of this is guessing, presuming or anything other than fact. Until
very recently I was a BT operator both inland and international. 

Firstly, you must go via 100 or 155. The reason for this is simple, payphones alone are missing one vital piece of equipment for detecting tones - the operators ears.
Yes, believe it or not the only way an operator knows money is inserted is by listening and counting. All tones are the same frequency, well if they're not, I never
noticed and I'm sure no other operator would if they weren't. 

This is absolute 100 per cent operator manual - 

   10p three short beeps 
   20p four short beeps 
   50p one long tone 
   £1 two long tones 

Though I don't know the exact lengths, The 1000 Hz is about right but for the duration I would have thought it a little longer than 350 ms but hey, I'll tell you exactly
how to be certain. 

Contrary to some peoples' beliefs the speechpath does close from the payphone when money is inserted though this has nothing to do with the operator, the
operator will close the speechpath to the destination though. The operator, having closed the path to the destination then asks the person in the payphone to insert
money. The operator then listens to the tones and number of them and then enters an amount into the cost box on his screen opens the speech path back up to the
destination and completes the call. 

Once the time duration has expired the call will be represented to the first available operator who will then go through the above process of collecting money again 

This is how to determine the tones exactly, it will cost you a couple of quid:- 

Get a friend to have some recording equipment ready, you could even do it to your own answerphone. 

Ring the operator from a payphone, telling them you're having difficulty getting through to your friends number. 

Once the operator connects you and asks you to insert money stick in say a fifty, that'll give you plenty of time, the operator will probably warn you not to put any
more money in unless you are told to, ignore this. 

Give it about 20 seconds to let the operator disappear. After this insert your coins, put in a ten, give it about 20 seconds and then insert your next coin do this for
the 10, 20 50 and pound. You will actually lose this money as it won't register on the payphone (red boxing UK is purely operators ears) once you've inserted the
coin the payphone will appear dead, this is where the speech path to you is closed, fear not though the speech path to the party you called is open and they are
hearing the tones exactly as an operator would so if they're recording, presto, you have all the uk red box tones, jeez, if you get your computer to answer you've not
got far off ready made wave files with a little editing. 

One word of caution, if you're sending these to an answering machine remember they often turn off when theres no input so whilst your on the phone happily
inserting your coins, recite the Koran backwards or something. This will ensure that whilst the speech path to you is open the answering machine is getting some
input and stays switched on, wouldn't want you wasting your 2 quid on BT for nothing now would we. 

Well thats it for now, look forward to seeing plenty of red box tone wav files on the group soon. More to come, in the meantime if you have any questions regarding
100 or 155 please feel free to ask. 

Zeno