Update on rotary phone refurbishment

In my last post, I suspected problems with the rotary dial on the Automatic Electric Monophone model 40, and a wiring problem on the Northern Electric 302, both of which kept me from being able to successfully pulse-dial through the HandyTone 502 analog adapter.

After a quick wiring check on the 302 and a lot of tweaking and oiling of both dials, I have to throw in the towel on getting these two to pulse-dial. Both need to have their centrifugal governors (the part that regulates the dial’s return speed) adjusted: the 302 pulses too slowly and with some irregularity, and the Monophone 40 pulses too quickly. I have read that telephone technicians of the past had to practice dial repair for a week under supervision before becoming competent at it. That is to say, the final touches are definitely beyond my skill level, and with a voice-driven workaround available, I’ve decided to call these phones “complete”–for now. I’m a tinkerer and may get adventurous some day and rip the phones apart once again.

6 thoughts on “Update on rotary phone refurbishment”

  1. Another announcement from Nerd Vittles today leveraging google’s speech recognition to do directory lookups. If I drag my arse long enough someone will get speech to dial working for me.

  2. I know this entry is old, but if you still have your rotary phones there may be hope. Over on the PBX in a Flash forum there has been some recent activity on speech recognition (using the Google speech to text API) with extremely good results. My goal is to hook up an ancient rotary phone to my Asterisk/FreePBX box and use verbal commands only for dialing, but I have not had time to devote to this project yet. Project is here: https://github.com/zaf/asterisk-speech-recog

  3. If you can see the governor on the back of the 302, try giving it a small spritz of lubricant such as a graphite or Teflon-based spray lubricant. Even good old WD-40 works pretty well but I think the ones that leave a residue of graphite or Teflon particles may last a little longer. Note if you use a Teflon spray, avoid breathing the fumes at all cost, because I hear that Teflon in the lungs is not a good thing at all.

    Basically, any kind of lock or gun lubricant would probably work pretty well. You want to get it on the inside of the outer wall of the governor and if you get too much, you may have the opposite problem of the dial being too fast. So spritz VERY lightly, work the dial a few times, and if it’s still not up to speed try again.

  4. Hobby, of course! Two things spark my interest in these old phones. First, the enjoyment of the old-fashioned, built-to-last phones and the styling of their era. Second, the challenge of integrating technologies that are seventy years apart and being able to say, “it works!”

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