sundance-communications.com/forum Forums General General Telephone & Systems Information WEAK BELL IN OLD PHONE

hi,

i just got an old (1970's mod 510 desk phone. the line cord was cut from the inside. it is wired for two lines. green and red (tip and ring), yellow and black (spares?)wired for another line.also had a buzzer, white and blue wires, which i removed. i wired in a moduler jack, and attached green and red to the j-block/strip, under the dialer, where the original green and red wires were from the old line cord. the phone works fine, can dial out and receive calls clearly. one problem tho. the bells ring very weak. i have the bells adjustment on loud, and the bells are all the way apart like they should be. could the solenoid for the bell be weak? the clapper barely moves. also, the rotor switch for the lines pushes down also, and activates/disactivates a set of contacts. what is this for?

thanks for any help,

bob

Check to make sure the capacitor is good and is wired in with the bell.

this link might help: Bell system practices

I PMd ya with another link/ Almost looks like this was/is a 2 line model. Looks like a lot of ooptiions for how you want the phone to behave.

Anyway,

Here are the possibilities, depending on your model:

510A/B

R B SL/R S
-----------------
1 2 A K
L2 L1 A K


510 E/F

R B SL/R S
-----------------
1 2 A K
E1 E2 A A
L2 L1 A K
L2 L1 1 2
GN R L2 L1


I PM'd ya with a link to a schematic.

As for the weak bell, what are you using for a telephone company and how many phones do you have on that line?

-Hal

The pushbutton feature is used to activate an intercom buzzer in the event that the second line is used for a manual intercom link.

Hal is right...if you are not on a real telephone circuit, you may not have enough voltage or current to ring the ringer. Take the phone to a neighbor who has real telephone service, and try it.

A capacitor "not wired in" would not be the problem, because the phone would put a short across the line, and you would get a pre-trip on incoming calls, not a weak sound.

Bob:

Have you checked the bias spring on the clapper? For normal CO line operation, this spring should be in the high, or "hooked" position.

thanks all!

i have at&t, used to be bellsouth for service. i have two cordless phones, no bells, and a regular landline phone, no bell, but plays music when a call comes in, and now this old phone. i get around 54vdc on the tip and ring comming into the house. how would i check the ring voltage? isnt it usually around 100vac?

bob

...i can remember when i was about 16, around 1976, my neighbor used to bring me to work with him sometimes. he worked in a central office alone. he showed me how to trace a call one time. the co still had mainly trunks with a electro-mechanical step/rotary switch in each one. i forget the complete process for tracing a call, but i know u had to watch and count the steps for each trunk, and i forget how, maybe the rotary switch pointed you to the next trunk to go to! alot of running around in isles filled with trunks! lol

ev607797,

i checked the spring on the clapper. there are two spings. a thin one that is hooked through a u shaped slot between the bells. and a thicker one that rest near the bottom of the adjustable bell. is this correct?

bobo the gongs are not supposed to be all the way apart. if you hold the armature against the magnet one way there should be about 18-20 thousands guage by eye, moved to the other side the same thing. the clapper should strike the gong.the thin one is the one EV spoke about that is the bias spring the other one was used primarily to shut off the bell in off position.