Help with TT Dial...

[DavePEI]

It isn't too often i have to resort to asking for help with a problem, but this is one case so far I haven't been able to solve.

I had a 2500DM which had a bad TT dial (broken Ferrite, resulting in its being way off tune). On that phone, all functions worked, except it couldn't dial due to the bad ferrite.

It wasn't a phone I cared about a lot, so I ordered a Premier replacement TT dial from OPW (their SKU# 24805), figuring it would work well. (Diagram below showing the Premier diagram)

Now, the Premier has fewer wires from it but was advertised as a replacement for 2500s and 2554's. SO, I put it in, and tried it out - no audio. One lead didn't match any of the descriptors on the network....

Seems these aren't compatible with all 2500s - it won't work on a 2500dm with a 4228B network.

First of all, if you follow the markings on the board of the TT pad, it says the Red wire should
go to E2 - there is no E2 on a 4228B,

Wire on Pad --> Network Terminal
Blue -->> GN
Red --> E2 ? ? ? Doesn't exist on a 4228B network.
Red/Green --> R
Orange/Black --> C
Black --> F/L2

I did try jumpering the Red lead to each terminal on the network with no change.

With this pad installed, you lose all audio - replacing it with the original 35A3A dial, even though its tones are off due to a cracked ferrite, and the audio is back, although with tones
which are off frequency.

Back to this, NADA.

I do have a 35AF3A dial coming from Seattle - I may have to wait till it arrives.

It seems to me there may be a dial inhibit pair which isn't taken into consideration on this dial.

I have another eye shot to get today, but no doubt I will be back at it tomorrow when my vision clears up again.

In the mean time, it is driving me buts. As I said,, it isn't that the phone is terribly important to me - it is more of an intellectual exersize, and I truly hate to let anything beat me. I will eventually have the other 35 type dial arriving, which should fix the problem,but sure would like to figure out how to get this dial working in the phone.

Any ideas?

[poplar1]

E2 is just a spare terminal. On WE networks, you can use "T" or any other spare terminal. The purpose is to connect the red dial wire to the red transmitter wire.

By "spare terminals" I mean that they don't connect to anything inside the network:
L1, G, L2, S, T, and in the case of Touch-Tone networks, F (no dial filter between F and RR).

In the original WE wiring, "T" is used to connect the red dial wire to the red transmitter wire. "S" is used to connect the white receiver wire to both the red hookswitch wire and the W-BL dial wire.

Also, you show the black dial wire going to F/L2 (?). It should go to RR on network.
The brown hookswitch wire should be moved from C on network to L2 on back of the Premier dial.
The green dial wire should go to F on network.

[DavePEI]

The connections I mentioned in the initial query were those which OldPhoneWorks told me to follow - those on  the dial. Obviously, they won't work on this dial and this network.

Oldphoneguy: I would use the contact points that are listed on the back of the TT dial.

I will try your suggestions tomorrow. I had another shot in one of my eyeballs today, so my vision is very bad today. I will try this tomorrow when hopefully my vision is a bit closer to normal.

Dave

[Victor Laszlo]

The terminals that are not connected to internal components are called "blind" terminals. But the bigger question is...why didn't you just take a working 35-type from a scrapped phone? There must be a dozen in my collection that I would gladly cannibalize and send you a dial, free.

[DavePEI]

The terminals that are not connected to internal components are called "blind" terminals. But the bigger question is...why didn't you just take a working 35-type from a scrapped phone? There must be a dozen in my collection that I would gladly cannibalize and send you a dial, free.

The answer is equally simple - I didn't have one I wanted to scrap, and no-one spoke up before I ordered these. Believe me I would have preferred to find an original. However, I did later locate several which I bought for spares (see the wanted ads), but not before these were ordered (since they said they would work on all 2500s and 2554s) The other type 35AF3A's will still take a couple of weeks to arrive from the US.