[VoIP] SS400 awake

[David Josephson]

The switchroom here is beginning to take shape. We finally migrated the 
office phones (what used to be a one man shop with a couple helpers is 
now five people full time making microphones) from a KTU-less system and 
an answering machine to an AT&T Merlin Legend system with display phones 
and voicemail, which has a rather convoluted programming interface but 
works well.

Next step was the EM switch, and the WE Switching System 400 that I got 
from Larry Tighe is now rewired after its disassembly to come upstairs, 
and working. This SS400 is basically a stripped-down 756A, which 
provides (in one rack of three slides) 8 lines of 1A1 key phone service 
and a 40 line crossbar intercom with dial pulse register and junctor 
circuits like those in a 756A. There are no trunks per se, but three 
"universal line" circuits which provide single-digit links to external 
tie-line, paging or dictation trunks.

I am still looking for a good way to provide touch tone calling on the 
SS400. I have some tone-to-pulse converters but that seems like a real 
hack. The BSP's suggest either of two types of touch tone receivers. I 
have a pair of the better A-type receivers, but these require a J58847AE 
L1 relay applique to translate two-of-seven (individual tone decode 
outputs) to one-of-ten plus steering. There is an option for internal 
mounting of the "junior" C-type touchtone receivers, which are basically 
the circuit cards of a 427B or C decoder mounted on a rack plate. I have 
an external rack for mounting decoders etc. but would really like to 
keep everything inside the switch.

So ... I would like to find a precise dial tone plant (either the 
correct 404C tone generator or something like it), two J58844A touch 
tone receivers or equivalent (one rack unit, one-of-ten output), and two 
AF156 relays to make the required modification to the dial pulse 
register circuits. Anyone have these pieces in their trading pile?

--
David Josephson