View Single Post
Old 18th May 2021, 12:28 pm   #9
Dave Moll
Dekatron
 
Dave Moll's Avatar
 
Join Date: Feb 2005
Location: West Cumbria (CA13), UK
Posts: 6,127
Default Re: Dialling problems with 232 and bellset 26

Quote:
Originally Posted by russell_w_b View Post
Ah... See what you mean now - you're leading the plug into the telephone via the bellset.
As per the approriate N diagram except that I'm using the master socket capacitor rather than that in the BS26

Quote:
Originally Posted by russell_w_b View Post
But is the terminal on which T3 connected to the bell in any way? It shouldn't be. It should go straight to the telephone speech cct.
It goes both to the telephone and the "earthy" end of the bell - otherwise there would be no return path for the ringing current from the "ringing" wire. T1 (red, B leg) is not connected to the bell. It uses B9 (no internal connection) as a means to pass this to the telephone.


Quote:
Originally Posted by russell_w_b View Post
1600 Ohms sounds suspiciously like a pair of bell-bobbins to me, plus carbon mic and ASTIC winding.
I have little doubt that this is correct. It may be that this was a red herring, but I am still left with the conundrum that opening the pulsing contacts doesn't break the loop (as needed by LD dialling).
__________________
Mending is better than Ending (cf Brave New World by Aldous Huxley)
Dave Moll is online now