AE 80 won't ring (Well sort of)

[novarlynx]

Hello everyone here, I'm new here. Got a small collection of rotary phones, all of them Western Electric except one.

I just got an AE 80 in black on ebay for pretty cheap and everything in it works except the ringer. Well sort of.

Whenever it receives a call, the hammer just wiggles, does not get close enough to strike the gongs.
Here's a short video I recorded of it attempting to ring, when called from an extension on my PBX using a WE trimline phone:
https://drive.google.com/file/d/0Bwd7P_RGT4hbWVp1QVpIRWxQMlk/

Here's what I have done so far to troubleshoot:
1. Metered the capacitor -- 0.3 µF
2. Metered the coil resistance -- 4k Ω
3. Wired the coil directly to the phone line -- did the same thing as in the video.

I've attached a few photos of the phone. I'm in the process of restoring the housing.

[Jack Ryan]

Your phone contains a frequency ringer and was once used on a party line. Its intended ringing frequency should be printed on the bell motor.

Try rotating the gongs to get them closer to the clapper. You might also try moving the clapper weight slightly.

Jack

[novarlynx]

Grr had a feeling it was a frequency ringer. I thought maybe the thing was just old and needed a cleaning at the very least.
Those dang party lines! lol

So if I were to replace this ringer, what should I look for so that I get one that isn't a frequency ringer? Is there a part number I can search? OR what frequency should I look for so it'd work on a normal phone line?

Also I'll try moving the gongs, I didn't think of that.

[Jack Ryan]

Try the adjustments first - your ringer is a low frequency ringer so there is a chance it will ring.

Attached is a straight line ringer - notice the different clapper weight and pivot. Also on the ringer where it says "RINGER" it would normally be preceded by "SL" but in this case there is some damage to the transfer.

I have also attached a picture of the base where the ID is printed. Yours has XX which means no ringer. In this case, if required, the appropriate frequency ringer was fitted by the operating company as necessary. On the image I posted it has SA which means "straight line" (ie normal) with an adjuster (the ringer volume control). SL would be straight line with no adjuster (cheaper).

Edit: Sorry about the dial number plate. I doubt there was really such an exchange.

Regards
Jack

[novarlynx]

Number plate made me chuckle.

I tried moving the gongs around and playing with the weight and I got it to ring very softly. I mean you can hear it but it's pretty quiet.

So i'd like to replace this ringer eventually. I found what looks like a straight line ringer on ebay for $25 but that price seems real high considering that is how much I paid for the phone too. I'm a little hesitant to dump that much money into an old phone that's still relatively common to find anyway.

If anyone may have an extra ringer I'd be interested in getting it as long as it won't cost too much. That's probably a shot in the dark though.

[unbeldi]

In your pictures you are showing us the capacitor of the ringing bridge. It has the part number D-68961-A.
The value of this capacitor is 0.2 µF (microfarad). [PS after re-reading: you measured it at 0.3 µF]  Automatic Electric used this value only on ringers with a frequency of 30 Hz and 33 1/3 Hz in the decimonic and harmonic ringing systems, respectively.

30 or 33 Hz is not far from the straight-line ringing frequency at 20 Hz, and this explains that it at least responds faintly.  I have been quite successful at retuning a 33 1/3 Hz Automatic Electric ringer simply by moving the clapper weight outward as far as possible away from the pivot point.   An additional modification that should improve things, is adding additional capacitance in parallel to the existing D-68691-A.  I would try adding a modern unpolarized capacitor of ca. 0.5 µF across the terminals of the gray metal can.  For a straight-line 20 Hz ringer, Automatic Electric used a 0.7 µF capacitor.

You can find these at Radio Shack, for about a dollar, probably, and if you get them from China via eBay, you get at least a dozen for a buck without extra shipping charges. It can take a couple of weeks (or more) though.  It's actually good to have a small supply, because they can be used on other phones as well. 0.5 µF (or 0.47) is a standard value used for many ringers and their replacement comes up here on the forum quite frequently.


PS:  here is a supply of these.   0.47 µF  630V.
These have a rated breakdown voltage of 630V which is good for connecting to a real phone line that comes from an outside pole. As you see in your picture, the old capacitor is rated at 1000 V !
More typically, you can get away with less, but the very bottom should at least be 250 V, but the cost difference is miniscule.

[compubit]

I thought the AE straight line ringer was .4uF? I'll check when I get home. Regardless, using a .47uF should be good to get a ,,stronger" ringing signal.

Also, since you're connecting to a PBX vs. a LEC line from the outside, the 600V breakdown range should be fine.

Jim

[andre_janew]

I love the dial card on Jack's phone! 

[unbeldi]

I thought the AE straight line ringer was .4uF? I'll check when I get home. Regardless, using a .47uF should be good to get a ,,stronger" ringing signal.

Also, since you're connecting to a PBX vs. a LEC line from the outside, the 600V breakdown range should be fine.

Jim

You are correct.  I should have stated for a 20 Hz ringer they used the 0.7 µF value, which is what I intended here.