We have to admit that this retasked retro phone wins on style points alone. The fact that it’s filled with so much functionality is icing on the cake.
The way [SuperKris] describes his build sounds like a classic case of feature creep. Version 1 was to be a simple doorbell, but [SuperKris] would soon learn that one does not simply replace an existing bell with a phone and get results. He did some research and found that the ringer inside the bakelite beauty needs much more voltage than the standard doorbell transformer supplies, so he designed a little H-bridge circuit to drive the solenoids. A few rounds of “while I’m at it” later, the phone was stuffed with electronics, including an Arduino and an NFR24 radio module that lets it connect to Domoticz, a home automation system. The phone’s rotary dial can now control up to 10 events and respond to alarms and alerts with different ring patterns. And, oh yes – it’s a doorbell too.
In general, we prefer to see old equipment restored rather than gutted and filled with new electronics. But we can certainly get behind any effort to retask old phones with no real place in modern telecommunications. We’ve seen a few of these before, like this desk telephone that can make cell calls.
Very nice! Nothing beats the sound of a real metal bell ringer. Great functionality from a very robust device. Cheers!
We have a table top model 51 here, connected via a DTMF module to our fiber network modem and after some TLC it looks and works great.
The metal bells are really astonishing. These are not loud or obnoxious like piezo buzzers, but no matter where am and no matter what background noise is going on, I always hear it ring. I suspect the reason behind this is A. the fact that a big metal resonating dome simply moves air in more directions and B. the two tone bells are chosen to be frequencies that do not occur together that often, so in most scenarios one tone will always get through.
Shame that a PTT Ericson model 51 was gutted like that. Judging by the outside, the innards should have been fine. The only thing these phones suffer from is crusty carbon pickups. The pickups are the same as the model 65 which you can salvage easily.
The mod itself also was completely unnecessary as it is entirely possible to implement all these function externally. With a DTMF module for VOIP routers you could easily hack it to do all of this and still be usable as a phone or input device.
In fact if you want to do this with the table top version of the 51 instead of this wall mounted version, you’d have no choice as the table top does not have enough room inside for this particular mod.
Cool project!
BTW, can someone fix the coiled cord, please? It’s driving me nuts!!! (c:
And the handset is turned the wrong way.