My 302.

[benhutcherson]

This may be a long shot, but I've often had a problem on 302s with wires touching the ringer gongs, muffling them.

It's very important on a 302 that the wires all be routed as they were when the phone was new.

[Stephen Furley]

Thanks for the suggestion, but it's not that; when it's not ringing the ringer's not even trying to move.

I think it's unlikely to be a faulty ringer, if it was that then I wouldn't have got anything out of it at all, not the occasional ring that I have had.  My best guess would still be a bad connection somewhere.  I suppose a faulty capacitor is also a possibility, that's why I wanted to connect the generator directly to the ringer, but it's very difficult to see which wires are which.  I could try shorting out the capacitor; since the phone's not connected to the line, only to the ringing generator there's no d.c. there so the bell should work quite happily without the capacitor being in circuit.

[Dennis Markham]

Stephen I have to confess that I'm confused by your description of how the phone is wired.  A picture is worth a thousand words.  I'm not sure what a ringing generator is so the confusion is more than likely in my head.

Check out this posting.  There are 3 wiring diagrams made simple.  Since you said you have a two wire ringer, check the one titled "Wiring for Model 302 H1 - 2 Wire Rigner.

http://www.classicrotaryphones.com/forum/index.php?topic=890.0

[Stephen Furley]

Stephen I have to confess that I'm confused by your description of how the phone is wired.  A picture is worth a thousand words.

Thank you for the reply; I'll try to get you a picture either this evening or tomorrow.

I'm not sure what a ringing generator is so the confusion is more than likely in my head.

One of the little hand-cranked generators that were used mainly with local battery systems, and old switchboards, to supply low-frequency a.c. ringing current.  Often called a magneto.  Looks rather like a desk pencil sharpener, square box with a handle sticking out of one end, and a cord coming out of the other.  Lets me send ringing current to a 'phone without connecting it to a line and calling it.  Very useful when diagnosing ringing problems and adjusting bells.

Check out this posting.  There are 3 wiring diagrams made simple.  Since you said you have a two wire ringer, check the one titled "Wiring for Model 302 H1 - 2 Wire Rigner.

http://www.classicrotaryphones.com/forum/index.php?topic=890.0

I've looked at that before.  The problem is that the wires in mine aren't these colours; since most of them are the same colour I can't work it out from this.  The diagram I was using yesterday shows the ringer effectively connected between the green and yellow wires in the line cord (Tip and Ground I believe), in series with the capacitor obviously.  This sounds like the way we used to do shared service; your description puts the  ringer/capacitor combination between L1 and L2, which seems more logical on a normal 'phone.  However, applying ringing current to these two points does not ring the bell.  Also, your circuit has three wires going to the L1 terminal, which is what mine has.

I've now removed the old line cord ready to fit the new one once the ringer is working.  If I can see which wire is going to 'R' on the dial, then the other one should be one side of the ringer.  I'll give the spades a good clean, and try putting ringing current on this wire, and the one on terminal 'K' which isn't going to the capacitor.  This should connect me directly to the ringer, and since there's no d.c. present the bell ought to ring.  It this works then I'll try again between L1 and L2 which would add the capacitor to the circuit.  There can't be a short between L1 and L2 because speech is working fine.

I did consider that the ringer might be a frequency one, but this seems unlikely, there are no markings on it, and it has rung, albeit briefly, on 25 Hz. in the past.

[Stephen Furley]

It looks like bad news.  I've managed to identify the two wires going to the ringer, and to remove the ringer from the 'phone.  These two wires are coloured, though with age they're sort of redish-brown and blackish-brown.  I've applied ringing current directly to these wires, and still no luck.  I've also applied d.c., at about 36V, and the ringer shows no tendency to pull one way or the other when I do this.  I've attached a pair of insulated croc clips to the solder blobs where the wires are joined to the coil windings, and connected one of my test sets which has a neon which flickers when it sees ringing current; it does indeed flicker, so I don't have a break in the wires connecting the ringer.

The bias spring is in the centre position; I've tried moving it to the other positions, but this makes no difference.

I don't have my test meter today, I lent it to somebody at work, and left it there when they returned it.  I'll meter the windings tomorrow; what should the d.c. resistance of them be?

I find it hard to believe that the ringer is dead; if it was then it wouldn't have rung again, very briefly, yesterday.   There's no sign of any physical damage to the ringer, indeed it looks to be in very good condition.  The only marking on it, other than the date is 'BIA' , near he hole where the hammer comes through the metal frame.  Since the ringer has the correct date I'd rather not replace it if possible.  Also, it would be difficult to find a replacement here.  I'm pretty sure that the ringer in my other 302, the one that spent a few years under water and full of mud, is dead.

[Stephen Furley]

It is bad news; one of the ringer coils is open circuit.  The other coil is reading just over 1k Ohms; I can't get an exact reading because the battery is low on my meter, and I can't get zero on it.

I know somebody here advised against dismantling ringers, but I think I'm going to have to try to repair it.

The 302 now has its new cords, and it's looking much better.

Benhutcherson, I see what you mean about routing the cords, the new ones are quite a bit thicker than the old ones were, and it took several attempts to get them arranged in a way that works; I'm still not sure if it's correct though.  The old ones were definitely wrong.  It was also quite difficult to fit the plug; there was a lot of quite thick wire to fit inside.

[Stephen Furley]

It was a bit tricky, but the ringer is now repaired, and the 302 fully working.

The next ringing problem is with the AE 40, which I've now fitted with a proper line cord, but which needs 'unconverting'.  Hopefully that should be working this week.

I've paid for the Kellogg, so hopefully that should be with me in about 2-3 weeks.  The seller has received the cheque for the 150 candlestick; it will take a few days to clear after he pays it in, so I should receive that sometime next week.