woody_unreal:
So. you have a Regulator outputing 4.5v one one unit, but when u hook it to more that one it drops ?
No, sorry, not at all must be my description.
JimG:
The switching transistor for the speaker is in an open collector configuration. That is, the switch is between -speaker and ground.
Jim - interesting. I take it that diagnosis matched my symptoms, so to speak? Where do I go from here? The only way I could effectively measure the voltage of each doorbell independently was to group the speaker positives - but can that work??
THANKS
Grumpy_Mike:
Sorry can't follow the words on what you did, do you have a schematic?
I've drawn a crude diagram of my setup. Does this help?
