AE 40 Ringer Mod

[Ed Morris]

I recently picked up an Automatic Electric Model 40 at an antique store.  One of the issues is that it has a 42Hz frequency ringer installed.  In an earlier thread, http://www.classicrotaryphones.com/forum/index.php?topic=18171.0 Poplar1 gave me a link to a straight line ringer on eBay, which I purchased.  When it arrived, I found that it is smaller than the original ringer. 

The two mounting holes for the frame were the same, but the the mounting bracket for the condenser wouldn't fit when the SL ringer was mounted, so I had to modify the mounting bracket by cutting off the arm that supported the rear of the frequency ringer frame, and cut away some of the bracket to clear the rear of the SL ringer.

[Ed Morris]

The rear of the new SL ringer doesn't line up with the original screw hole for the frequency ringer, and I didn't want to drill a hole in the bottom plate, so I just slipped a grommet through the hole in the SL ringer's rear support.  It rests against the bottom of the plate to stabilize the rear and cushion it as well.  The last image shows the SL ringer and condenser can installed on the bottom plate.

[Ed Morris]

The original frequency ringer used a .7uF capacitor in the circuit, and the SL ringer will actually work with the .7 cap, but I decided to go ahead an install a .47uF capacitor, which is the closest I had to .4, which is what the SL ringer specifies.

Since there is plenty of room behind the smaller SL ringer, I decided to mount the new .47uF cap behind it.  I unsoldered the two leads from the .7 side of the condenser can and soldered them to the new capacitor, so all the wiring can go back as it was.

The new ringer works well and has a nice sound in test mode.  I'm still waiting on my new line cord and handset cord to arrive for final testing.

I probably could have fabricated a new bracket for the condenser can, and saved the original bracket instead of cutting it, which would have made the mod completely reversible. 

[Ed Morris]

Success!  I got my line cord and handset cord installed and I have dial tone and a working ringer.  In addition to swapping out the frequency ringer, I cleaned the dial in an ultrasonic bath of Dawn detergent and water for about 30 minutes.  I rinsed the dial in distilled water, followed by compressed air.  I let it dry for several hours, and was disappointed that it was still balky, but as soon as I lubricated it with some clock oil, it worked like a charm.

I cleaned the body with Dawn and warm water, followed by a lot of buffing and polishing, starting with Novus 3, then Novus 2, and a final shine with Novus 1.  It looks much better than when I brought it home.  See the link in the first post for a photo of the "before" state.