|
Vintage Telephony and Telecomms Vintage Telephones, Telephony and Telecomms Equipment |
|
Thread Tools |
17th May 2021, 12:20 am | #1 |
New Member
Join Date: May 2021
Location: Southampton, Hampshire, UK.
Posts: 1
|
Direct-Dial into PABX1
Hello All! just joined the group,
does anyone have a dtmf to pulse converter? or even a cct diagram for one? I am currently building a relay set to enable incoming BT-Line calls to direct dial into my PABX1 I am told the Post Office/BT had what was known as the 43A converter but these seem to be quite rare now. Regards Nick |
19th May 2021, 9:32 pm | #2 |
Pentode
Join Date: Aug 2016
Location: Dunstable, Bedfordshire, UK.
Posts: 140
|
Re: Direct-Dial into PABX1
I've done some work in this area but never a DTMF to pulse converter. I've never heard of one being commercially available either.
If it was me I would be looking at some sort of Data Access Arrangement to interface to the public line then using some sort of micro controller (Arduino is very good for this kind of thing) to interface in to a DTMF chip that can decode DTMF signals and pass them onto some sort of relay on the PABX1 side that can generate the pulses. It certainly wouldn't be a trivial project - many skills would be required not least a good understanding of the C programming language. Also a bit of a head scratch would be needed to get the things to recognize a ring-up tone and answer the call automatically to connect to the PABX1. |
19th May 2021, 10:03 pm | #3 |
Dekatron
Join Date: Feb 2005
Location: West Cumbria (CA13), UK
Posts: 6,130
|
Re: Direct-Dial into PABX1
There was a similar discussion on the (members-only) Telecommunications Heritage Group forum, but the only reference I can find to anything at all commercial is http://beefchicken.com/comms/atctonepulse.
__________________
Mending is better than Ending (cf Brave New World by Aldous Huxley) |
20th May 2021, 9:58 pm | #4 |
Octode
Join Date: Aug 2005
Location: Saltburn-East, Cleveland, UK.
Posts: 1,786
|
Re: Direct-Dial into PABX1
Hi, you could exploit a Mitel Smart 1 dialler.
They occasionally crop up on eBay (sadly I can only see ones in America at present) and can do tone to pulse or pulse to tone conversion, setting them up is done using a standard DTMF phone and I'm sure that the manual is available somewhere online. Regards Andrew |
20th May 2021, 10:15 pm | #5 |
Dekatron
Join Date: May 2010
Location: Greater Manchester, UK.
Posts: 18,724
|
Re: Direct-Dial into PABX1
You beat me to it Andrew, I just got mine out to try, and reminded myself how to programme it.
*0# 100 0 (for port 1) 987 I reckon there will be loads of redundant Smart1 boxes screwed to the walls of factories and offices if only we knew where to look. Some small PABXs could convert that way, the Panasonic KXT, "A" series, probably many more. Ian Jolly is the expert on those converters used in the exchanges.
__________________
-- Graham. G3ZVT Last edited by Graham G3ZVT; 20th May 2021 at 10:26 pm. |