My SC 1543

[andre_janew]

Here is a picture of the transmitter cup in the SC handset.  Note that it is not as tight a fit as it would be in a WE G series handset.  Yet the receiver element shown earlier seems to fit like it belongs.  (Receiver is in top picture, transmitter cup is in bottom picture.)

[andre_janew]

Here are some pictures of the dial.  I cleaned it up with some WD 40 and then I oiled it with some 3 in one oil.  It no longer sticks, but it still won't dial properly.  It reminds me of an AE dial.  I'm not sure why it does.

[andre_janew]

The ringer doesn't seem to work.  Whenever there is an incoming call, the clapper will vibrate but it won't hit the gongs.

[unbeldi]

The ringer doesn't seem to work.  Whenever there is an incoming call, the clapper will vibrate but it won't hit the gongs.

The ringer in your set is a desimonic frequency ringer that is tuned to 30 Hz ringing frequency.  If you put your set on a 1A2 key telephone system it will ring.

You may want to try to move the large weight on the clapper further to the end of the rod to lower its resonance frequency.  You only have to compensate for 10 Hz difference. I have been successful doing this with Automatic Electric ringers of 33 1/3 Hz. 

[mdodds]

The feel of an SC dial seems closer to an AE to me too. Not quite the free spin when dialling to the stop, but not as much resistance as a WE either. Plus it has kind of a neat click sound to that's different than the others.

[andre_janew]

I removed the weight completely and it didn't seem to make a difference.  Also, the black wire is on terminal 15 right now.  It was previously on G1.

[TelePlay]

I removed the weight completely and it didn't seem to make a difference.

Now that raises an interesting question. Being a frequency ringer, totally removing the clapper weight would have what effect on the ringer's tuning? I would think the ringer's new frequency would be off the scale but which way? A slight adjustment of the weight could bring the ringer's harmonic down below 30 and it would ring on a 20 Hz or 30 Hz ring generator but totally removing it would do what to the ringer? Never seen that question asked before on this forum.

[unbeldi]

I removed the weight completely and it didn't seem to make a difference.  Also, the black wire is on terminal 15 right now.  It was previously on G1.

I didn't suggest removing the weight.

Removing it has the opposite effect of what you want to achieve. You want to make it heavier or longer.

[unbeldi]

I removed the weight completely and it didn't seem to make a difference.

Now that raises an interesting question. Being a frequency ringer, totally removing the clapper weight would have what effect on the ringer's tuning? I would think the ringer's new frequency would be off the scale but which way? A slight adjustment of the weight could bring the ringer's harmonic down below 30 and it would ring on a 20 Hz or 30 Hz ring generator but totally removing it would do what to the ringer? Never seen that question asked before on this forum.

The frequency of a vibrating reed depends on
(a) mass of the clapper weight.  The higher the mass, the lower the frequency.
(b) length of the clapper, or better the distance of the center of mass of the weight from the pivot point. The longer the clapper, the lower the frequency.
(c) the force constant of the reed, which is a spring. The stiffer it is the higher its resonance frequency.

So, removing the weight decreases the mass, therefore increases the frequency. Removing it is also equivalent to moving the weight into the pivot point, i.e. shorting the clapper to nearly zero length, again increasing the frequency.

[TelePlay]

That makes sense, thanks for that information. The farther out the weight, the "heavier" the "clapper weight" and the lower the frequency. And conversely, for a 16.6 Hz ringer, moving to closer to the pivot would "decrease" the "clapper weight" and increase the harmonic frequency.

[andre_janew]

I'll put the weight back on and put it closer to the pivot point.  If that doesn't work, then what?  Change ringer?  Add a capacitor?   The fact that it is vibrating makes me think it wants to work, but somehow it can't.  I did, however, find a date on the ringer of 6-61.   I don't know if that would be helpful or not, but I mentioned it just in case.

[stub]

 andre_janew ,
                How about this one from 1966 ? Check your PM . stub

[unbeldi]

I'll put the weight back on and put it closer to the pivot point.  If that doesn't work, then what?  Change ringer?  Add a capacitor?   The fact that it is vibrating makes me think it wants to work, but somehow it can't.  I did, however, find a date on the ringer of 6-61.   I don't know if that would be helpful or not, but I mentioned it just in case.

You need to place the weight farther away from the pivot point than it was originally.  See point (b).

[andre_janew]

Well, it quit working altogether now.  So, no matter where I put the weight, it won't work anyway.  I may as well take Stub up on his offer.

[andre_janew]

I printed a wiring diagram for my phone from www.classicrotaryphones.com/forum/index.php?topic=4388.0