atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Telephone Repairs & Equipment 500 set not working

I found an old 500 C/D set in my pile of phones.
It looks to be in good shape but has a few issues
1) I replaced the hardwire handset cord because it looked bad, but now the transmitter does not seem to work.
2) The phone does not ring. I checked the wiring but I'm not sure what I missed.
Any thoughts as to what might be wrong?
Thanks,
Jeff

The technician involved? :rofl: Sorry, Jeff, couldn't resist....

Did this work B/4 you changed the H/S cord? If you have another 500/2500 set around compare the wiring. This one may have been set up for various scenereos and could have just a couple wires in different locations.

To be honest I don't remember ever checking this phone out, it had been sitting around for a long time. So no, I am not 100 percent sure it worked before I changed the cord. I can check the wiring with some other sets I have.

Make sure that the black handset lead is on terminal B of the network and the red is on terminal R. As for the ringer, move the black ringer lead from terminal G to terminal L1.

did you check the transmitter itself ?

Yes, I just checked the transmitter in another handset and it works. Should I check the cup also?

I would think you could visually spot a bad cup , but it would be easy to swap it with a known good one

buzz the handset cord might be open. inspect the ringer for metal filings in the magnet also check the bias spring and gong settings; possible bad switch hooks.

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Got the link Jim. Will check it out later. Thanks again!

So Jeff what happened here? :shrug: :shrug:

I did not have enough time to fix it over winter break. It's on the back burner for now.

I'm home on spring break. Just tried to rewire the handset again with the same results. The phone still does not ring! This is too weird..

No way. The handset cannot possibly have any effect upon ringing. Are you sure that the ringer leads are connected as follows?

Black: Terminal L1
Red: Terminal L2
Slate: Terminal A*
Slate/Red: Terminal K*

* It doesn't matter which wire is on which of these terminals. A and K are just the ends of the capacitor.

I got the handset to work by switching out the transmitter cup.
All the the ringer wires are as you noted, but the wire going to K is white.

Where does the white wire come from? In a normal 500 set, the white switch hook lead should be on terminal F with a green wire from the dial. Are you sure that the wire on terminal K is really white? The older ringer coils had a solid slate wire that often appeared to be white.

The only other white wires would be from the dial and there are two of them: One should be on terminal R and the other on terminal GN.

The white wire in question is next to the red wire on one side of the capacitor, on the other side is the red/slate and black wires.
I've got another C4A laying around so I'm gonna try and swap them.
This is a lot of work for a 56 year old phone :p

Ringer:

Red-Terminal L2
Black-Terminal L1
Slate-Terminal K
Slate/red-Terminal A

Handset:

Red-Terminal R
White-Terminal R
White #2 (or green on modular sets)- Terminal GN
Black-Terminal B

Dial:

White #1-Terminal R
White #2-Terminal GN
Green #1-Terminal RR
Green #2-Terminal F

Switch hook:

Slate-Terminal L2
Slate/yellow-Terminal L2
Slate/green-Terminal L1
Slate/white- Terminal F
Slate/red-Terminal R
Slate/black-Terminal GN
Slate/brown-Terminal C

Line cord:

Green-Terminal L1
Yellow-Terminal G
Red-Terminal L2
Black (if present)-Insulated and stored

Ok so I swapped out the ringer and now it magically works! Amazing...thanks for the help Ed!

Now that the phone works, I can't help but wonder why the ringer went bad. Thoughts?

It was probably older than you....2 to 3 times over.

Yes, the date was 12-56, 5 months after my dad was born!
So it's twice my age plus some change

Jeff, you can check the ringer coils for "open" using a standard ohm meter. For a two-coil ringer, I think one coil should have a resistance of about 2500 ohms, and the other should be about 1000 (or maybe 1500). I can't remember for sure - Ed? Sam? Arthur?

If either coil reads "infinite," then that puppy is bad alright. Sometimes, if a ringer has been handled a lot, there can be a break inside one of the leads right where the spade terminal is crimped on. This is rare, though, especially with the older ringers that had heavy cloth-insulated wire for the leads.

Jim
**************************************************
Speaking from a secure undisclosed location.

With my meter set on 200K, I get anywhere between 88 and 100. This is with the meter on red and slate, and red/slate and black...am I doing this right?

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