Help with AT&T S201 Speakerphone

[mx103]

I’m hoping for some help with this. I have been requested to reconnect a AT&T S201 speaker phone on a Callmaster IV phone. The customer is convinced it used to work.
But I can’t get the speaker to power up. My connections are as follows:

Transformer 48V .4amp
Phone Other Line
-7 +8 -2 +5
|||||| |||||| ||||||
| | |
| | ------Wall Jack
| |
| |
|||||| |||||| |||||| Speaker
2wire line 4wire |
------S201 Speakerphone
Callmaster IV

 

[jordy5535]

Try using an 1151A1 or MSP-10 power supply. The power is fed over the 4th pair (white-brown)