Connecting a 713 Pendant Phone to a 746 circuit board.

[Sparks]

Is it possible to do this so the switches in the 713 replicate the function of the switches on the board ? If so, can anyone please tell me how ?

It doesn't matter if this isn't possible. I'm just looking for a small project to keep me busy during lockdown. Thankyou.

[Sparks]

PS. There would be no bell in this arrangement (other bells and warblers on the same line) so I believe it would be a matter of wiring the switch only to seize and release the line. I guess it would also be necessary to completely remove the existing switches from the board.

[JohnBHanson]

Actually it is not required to remove the existing switches from the board.

Look at page 2 on N746 and compare with page 1 on N813

Note that without a dial you have to connect T8 to T10

[JohnBHanson]

Or you could follow the enclosed diagram.... All the components could be fitted within the 713 base giving a neater installation.

[Sparks]

Thankyou John. I'll take a butcher's.

[WayneL74]

Hi sparks.

Yes you can do this. I transplanted a 746 board into a bell 50C to create a bell set 50D.

You do have to remove the cradle switch & connect one of the pads to a spare terminal which in turn goes to the 713 switch

I can dig it out & take some photos if that would help?

Regards,

Wayne

[Sparks]

Yes please Wayne.

[WayneL74]

Photos attached.

You will see the link wire from the induction coil to T11. If you follow the PCB track you can see it comes from one of the switch pads. T11 now becomes T20 on the N813 diagram.

Also missing on mine are the auto line regulation diodes & lamps. This because the board came out if a "value engineered" push button 746 that had been modded for some sort of PBX. You should still have these on yours.

Lastly as stated above if you are not using a dial then T8 & T10 in the bellset need to be linked.

Hope this helps.

Regards,

Wayne

[Sparks]

Thankyou for the pictures Wayne. There don't appear to be any external cables coming from your board. I know which terminals to connect the handset receiver and transmitter to but not where I should connect the gravity switch in the 713. As I said, it would only be for line seize and release.

Thankyou for your guidance this far and apologies if I'm not getting it!

[WayneL74]

Hi Sparks

There are no wires attached as I have still to find a place to site the phone that meets with SWMBOs approval.

I have attached a snip from the N813 diagram which shows the connections. Basically you have to link O on the 713 to where O goes to on the bellset (your 746 board) etc. The connections are therefore:

713 > "Bellset"
1 > 2
2 > 6
3 > 5
4 > 20 (This will be T11 if you modify your 746 board as suggested)
5 > 19
7 > 1
8 > 3
9 > 10

The diagram specifies 8-core cable. If you are wondering what you can use I suggest CAT5e computer network cable - it even uses the same colour code.

Regards,

Wayne

[Sparks]

Many thanks Wayne. I hope you find a suitable site soon!

[Sparks]

Wayne, I've successfully done this job this afternoon. Do you know if it's possible to connect more than one 713 in parallel to the phone board ? I might try that.

[WayneL74]

Hi Sparks.

Yes in theory you could do although they were never designed to be used that way.

Probably alright if you use 1 at a time.

Regards,

Wayne

[Sparks]

I tried but it wasn't successful. Not to worry - one is good enough.

[Sparks]

Following on from this project, I've now acquired a Desk-Mounting Drawer-Dial which I would like to fit to the circuit board. It's a relatively recent one (1972) with five connections but I'm not sure about the wiring. If I was using a Bellset 50, one wire would go from the dial to T20 but my board doesn't have a T20 ! I'd be grateful for any advice.

Thankyou.

[Dave Moll]

According to diagram N846, the pulsing contacts should go between T8 and T10 (with the strap removed). The one to go to T10 is common to the first DON (dial-off-normal) switch, the other end of which should go to T3. Th independent DON switch should go between T1 and T2.

Which contact is which can be identified by testing continuity as follows:

* the pulsing contacts are the only ones closed with the dial at rest
* while the dial is returning, these contact should show intermittent continuity
* at this time the contact common to the first DON will show steady continuity to its other terminal
* the other two contacts will remain isolated except from each other while the dial is off-normal

[Sparks]

Thankyou Dave. I've only had a minute or two to inspect the dial today but I have noticed its wires are blue, brown, grey, orange and pink so I'll bear that in mind as well.

[Sparks]

This is the dial in question.

[Pellseinydd]

Originally Posted by Dave Moll

According to diagram N846, the pulsing contacts should go between T8 and T10 (with the strap removed). The one to go to T10 is common to the first DON (dial-off-normal) switch, the other end of which should go to T3. Th independent DON switch should go between T1 and T2.

Which contact is which can be identified by testing continuity as follows:

* the pulsing contacts are the only ones closed with the dial at rest
* while the dial is returning, these contact should show intermittent continuity
* at this time the contact common to the first DON will show steady continuity to its other terminal
* the other two contacts will remain isolated except from each other while the dial is off-normal

Why not use diagram N813 which shows how to wire up a Tele 713,, Bellset 48 or 50 and the Dial Unit No 21 which you have?

[Sparks]

Pell, the problem is that the circuit board is from a 746, not a Bellset. Diagram N813 instructs connecting a wire from the dial to T20, but the 746 board has no T20. At least mine hasn't. That's the problem.