Wiring up a 1984 handset

[Pete_kaye]

I have a 1984 standard BT handset with rotary dial but it has no lead from the box .Can someone tell me where the 4 wires go .;I have a replacement lead; red,white blue and green tags.Or maybe a good website for information and schematic.

[Nickthedentist]

Hi Pete,

See: http://www.britishtelephones.com/t746.htm

and specifically: http://www.britishtelephones.com/pstconv1.htm#700

Don't worry too much about the resistor betweeen T4 and T5, it will work OK if you use a strap to join the two terminals, although it may "steal" too much current and make other phones on your line ring less well.

Nick.

[Pete_kaye]

I have checked this site and wired up as suggested .It works perfectly except the bell does not ring just a 'ting' noise when called .I am not using any other phones on the line .I am told it rung perfectly when last used afew years ago.It has the rectifier but no resistor .
Does any one know the BT code used by engineers to check the line .It used to be '175' but doesn't work now on any phone I try here.

[Station X]

175 Is the Subscriber's Automatic Line Tester (SALT) If you hang on you should get the message "You are connected to 01xxxxxx. Start test". You then replace the handset and wait ror a ringback.

The old ring back number was 174, but as far as I know it's no longer used and has been replaced by an 0800 number which I don't know.

Could there be a simple mechanical problem with the bell? Being AC there are no contacts to worry about. Check the adjustment of the clapper and gongs.

[russell_w_b]

Originally Posted by Pete_kaye

I have checked this site and wired up as suggested .It works perfectly except the bell does not ring just a 'ting' noise when called .I am not using any other phones on the line .I am told it rung perfectly when last used afew years ago.It has the rectifier but no resistor .
Does any one know the BT code used by engineers to check the line .It used to be '175' but doesn't work now on any phone I try here.

Try dialling 17070. There used to be a whole range of tests, but they have now been severely curtailed! 17070 (non-geographical test number) will give you a ringback, though.

[Nickthedentist]

The easiest way to ring your own telephone these days is to use a mobile phone, assuming you have one or can borrow one. It costs nothing, of course, if you don't answer.

Another "trick" is to use a modern DTMF ("touch tone") phone on the same line as the one you're trying to test. Dial 131 then press R ("Recall) then hang up, at which point your phones will ring. It doesn't have to be 131, but that's an easy one to remember and I think it's free (It used to be the Mercury access code, I think). Note that the phone has to be a DTMF one (pulse dialling won't work) and the recall has to be set to "time break" (as opposed to "earth").

As for the actual fault, can you take a pic of how you've wired it? That would definitely be the easiest way for us to check that you've done it correctly. Also, make sure it's plugged into your Master socket (just in case your extensions are incorrectly wired).

Nick.

[plumbweiss]

17070 opens up a whole raft of engineer tests, if you select 'fast test' and '1' when asked to confirm authorization, you can also ask the exchange to measure line loop impedance and DSL compatibility etc.

[russell_w_b]

Originally Posted by plumbweiss

17070 opens up a whole raft of engineer tests, if you select 'fast test' and '1' when asked to confirm authorization, you can also ask the exchange to measure line loop impedance and DSL compatibility etc.

Perhaps you can (still) around your way, but you can't around here! BT have seen to that... The ring-back facility works OK, but once past '1', an authorised mobile telephone number (no doubt belonging to a BT engineer) has to be entered! I suspect BT have grown wise to the number of punters using the test facility to establish the length of their lines to the exchange, and using it as ammunition in their fight to have ADSL enabled.

But I might be wrong...

[Tim]

17070 opens up a whole raft of engineer tests, if you select 'fast test' and '1' when asked to confirm authorization

NB. If you are not BT, you are, ipso facto, not authorised. Stating you are is illegal....technically. But they have to catch you of course!.


175 will still work on some exchanges (AXE10= System y) but takes a long while to connect. Returns basic line test and ring back. Will also return 0123456789 for caller display.

Re- bell not ringing.
Prove your socket with another phone. The likely hood is you have the line cord reversed. Swap over the wires on connections 9 and 19.

[russell_w_b]

Originally Posted by Tim

NB. If you are not BT, you are, ipso facto, not authorised. Stating you are is illegal....technically. But they have to catch you of course!.

Oh? I thought I was authorised because it's my line, which I subscribe to! I don't know what law I'm breaking given the ambiguity of the feeble 'if you are authorised...' I've used the facility at work many times, whilst liaising with the BT chaps, and they don't seem to mind.

That notwithstanding, 1267 used to work as a ringback on the Bridport exchange. 175 still works on my (Skelton) exchange.

[Pete_kaye]

Thanks for the hints .My other phones work fine from this socket and 17070 worked correctly but not ringing back with the 1984 handset.I have wired it as per the website given earlier in this topic so it must be afault with the ringers .I do get 4000R on my ohmmeter for the coils to the headset.

[Nickthedentist]

Originally Posted by Pete_kaye

...it must be afault with the ringers .I do get 4000R on my ohmmeter for the coils to the headset.

These never go wrong!

You should get 4000R across the bell coils (as you do), AND between the white and blue wires that go to the plug. If you don't, it should only take a minute to work out why

If you can measure 4000R between white and blue at the plug end and it still doesn't ring, then EITHER your master socket (or most likely, your extension wiring) is faulty OR the bell gongs are misaligned (their mounting hole is eccentric, so you can twist them to ensure that the bell's "hammer" just hits each one, producing a nice loud ring).

Nick.

Nick.

[Pete_kaye]

I have done more tests today.
1.The ring back only works from aTone phone not a pulse dial one (I have another phone that can be switched).
2.Using 17070 with both phones working results in the normal phone ringing back but not the '84 8746 oneif set up from the newr one
3.1471 reveals that my mobile was connecting on both correctly.
4.To what should the 2 white wires FROM the 2 coils be connected .One was T4 and nothing else so I switched it to T5/T6 which has the blue line on it but no change.The other white wire from the coil goes to T18 and then to white line in.
5.Should the space between the bells be as small or as large as possible ;neither work.The biggest gap allows me to get a ring manually by moving a lever at the coil.

[russell_w_b]

Try and divorce yourself from the 1471 thing. This only tells you that someone has called your line, not your individual telephone!

Connect as follows:

Incoming lead (plug on one end, red, white, blue, green spades on the other):

Red to T8; white to T18; green - don't use, but connect to T15; blue to T6; Make sure the following terminals are strapped:

4,5,6 to each other.

16, 17, 18, 19 to each other.

Regarding the series-wired bell-coils: L/H lug. of L/H bobbin to L/H lug of R/H bobbin. R/H lug of L/H bobbin to strapped terminals 4,5,6. R/H lug of R/H bobbin to strapped terminals 16, 17, 18, 19. Note that the white and blue incoming lead wires lead directly to the bell bobbin wires. Ensure that the bell armature swings sufficiently to carry the attached hammer between the gongs with a satisfying 'ting'. The gongs are eccentrically mounted and can be rotated to suit. Ideally, the hammer should not rest on the gong, but should hit it and bounce back.

Handset: White to T10, Red to T1, Blue to T3, Green to T2

[Gordon]

I had a similar problem and had to incorporate a 'bell capacitor'
See diagram below.

Gordon.

[russell_w_b]

Originally Posted by Gordon

I had a similar problem and had to incorporate a 'bell capacitor'
See diagram below.

Gordon.

The master LJU installed on the premises should include a bell capacitor! Any extension down-river being connected via three wires to terms: 2 (line -48V), 3 (ringing wire), 5 (earth).

It might be as well (for the O.P.) to check the red and white (line-pair) wires on the lead to the telephone. If they are reversed, the speech cct will be unaffected, but the bell will not ring, as the ringing wire will be reversed from terminal 3 in the master LJU in relation to the incoming line, putting the bell across the ringing capacitor instead of in series with it (and across the 470 Kilohm line-test resistor, also in the master LJU, as it should be).

This is evident from your (Gordon's) drawing.

[Pete_kaye]

I now have some success.I think the gong arm has been sticking as the wiring is correct and I know the phone used to be perfect on this line.On Friday I took the two screws out that hold the cover over the arm and waggled the arm around.It now rings but not on both bells just one .It doesn't quite sound right but I might try witch cleaner next -is this a good idea?

[Station X]

If the bell rings on one gong it's purely a mechanical problem. Make sure everything moves freely and adjust the gongs for loudest ring. I can's see how switch cleaner will help unless you intend to use it as a lubricant.