atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Telephone Repairs & Equipment BELL phone keypad doesn't dial out!

I received 3 Bell phones today and am very happy with only one of them. The two that do not work have the same problem, they do not produce a tone when a key is pressed,

I read on a previous forum that this was a common thing in W.E. keypads.

When a key is pressed the volume goes down, but nothing proceeds.

I heard it can be the transistor or maybe a bad connection?

Problem is where to start looking. Maybe you can help?

start by trying to reverse the polarity (swap the red and green wires )

OK. Could you explain how that would work for future seekers of this information?

The older touch tone phone were polarity sensitive, now they have a polarity guard in them so the line wiring is immaterial.

So you're just reversing the tip and ring so you get the battery on the correct side, or you could buy a polarity guard to put in the phone, that is if they still make them.

Here ya go polarity guard

I've had this issue on some of my 1A2 keysets. Flipping T&R at the block will solve the problem, at least for me.

Back in the day you were suppose to make sure ring was ring and tip was tip. I still do, just because it makes it right.

Remember:
There was a time when only Telco technicians could install telephones and work on the lines. We were trained to ensure that as justbill states: The ring was the ring and the tip was the tip, battery was present on the ring, ground was present on the tip, from central office to demarc, no exceptions. It made trouble shooting easier for the next guy.

Radio shack has them under a different name. Bridge rectifier.
Hook the Diode + and - to the T&R inside the phone and the ~ (AC) pins to the mtg cable T&R.

Tip and Ring? I thought those were Alexander G Bells two dogs.

"Radio shack has them under a different name. Bridge rectifier.
Hook the Diode + and - to the T&R inside the phone and the ~ (AC) pins to the mtg cable T&R."

Tsk Tsk! You're really going to confuse the guy, suggesting that! Ask yourself this: What happens when the CO line rings with AC? The diode bridge will rectify it, and then the bell won't work. Then we'll be back here, diagnosing THAT problem.

Here's what to do: Reverse the T & R at the closest point of connection to the phone.

If you want to convert the telephone so that it has a polarity guard, you need to wire the PG between the network terminals and the dial.

See, for example, BSP 502-523-401 (you can google it) and look for the schematic for the 2500DMG telephone set, which is a typical application. In the model number, the M stands for "Modular" and the G stands for "Guard". Note that the PG gets wired between the line switch and the network.

For a basic understanding of what the PG looks like and how it works, I suggest that you see BSP 501-321-100. (you can google that one, too) Most times, a quick check into the TCI library will give you the right answers.