Old Westminster Door Chime and New Doorbell Camera Solved

I recently bought a doorbell camera for my house that was built in the 1950's and has a beautiful old-school Westminster multi tone chime. Getting the camera to work with this was an exercise in frustration because of a device that comes with the camera. A mystery device that mysteriously allows the camera to work when the doorbell button is pressed and the chime is "activated".
This mystery device is often referred to as the "Puck". If you have installed one on your chime you know what I'm talking about.

What I have found is that this thing allows some current to flow to the camera without activating the chime so that the camera can function but it stops current flow through itself when it detects the button press. It does not use WiFi or Bluetooth for this as one might expect from a mystery device, but instead it monitors the current demand of the circuit. When the demand is equal to the needs of the camera, which is a high impedance device, it shorts the chime for only that amount of current. But when the button is pressed the impedance drops and current demand goes up, so it stops shorting the chime for a fraction of a second (presumably the duration of the button press), and then shorts the chime again.

If the chime is a single or two tone chime, there is no problem. The single coil of the chime striker gets it's pulse from the button press and you hear a Ding or a Ding-Dong. Job done, power goes back to the camera and you are good to go. BUT, if you have a fancy dancy multi tone like my Westminster then it rings, and rings, and rings....

WTF? I have the answer, and the solution.

Why does it do this? The multi-tone chimes have a motor in them. The motor has a wiper arm that continues to "press the button" so the motor continues to get power as it's other wiper moves over the notes of the other chimes. Then the wiper powering the motor gets to the end and no longer makes contact and, normally, stops until the next button press. But we have a Puck and a camera on that part of the circuit and lets just say they don't play nice together.

The camera during this round-about of the chime is losing voltage and will act like it has lost power. It will shut down and reset. It has a small battery or supercap in it to survive a single button press, but it cannot survive a few seconds of motor and solenoid draws. If you look for solutions online you get all kinds of advice about upping your voltage from 16VAC to 24VAC or upping the current capacity etc etc. That won't work. It's not a power problem, it's a timing problem with...wait for it...
The Puck. The puck does not function with a constant current device attached! It's function is to short the chime slightly, and this is key, slightly to allow power to the camera, which is now drawing max current during it's reset, and that small extra bit of current is Just enough to keep the motor, which is already spinning, to spin just a little bit further, and it's Westminster all over again. The dogs love it.

The solution I used was to go ahead and use the upgraded transformer I already bought, and wire it to the camera and the puck, but not the chime. I use the original transformer for the chime, and I got a bridge rectifier and a universal automotive relay to be my "chime" that the puck and camera are connected to, and I used the switch portion of the relay to be the "button" on my chimes.

The rectifier is for the DC solenoid of the relay. I simply wired the AC side of the rectifier as though it was a chime, and connected the solenoid terminals of the relay to the DC side of the rectifier. Even though the relay is a 12V relay, it will actually work fine at 24V or 16V momentarily without any problems. And it's cheap and off-the-shelf at any automotive parts store. No need to get a special order relay designed for 16vac or 24vac. Good luck with that.

Then I wire the switch portion of the relay like it is a regular button switch to the chime. Easy-peasy. Problem solved!

This will work with ANY chime. Also, it does not interfere with the original back door and side door functions of the original chime. If I want a camera on the back door too, then I have some options. However, the Puck and camera will work fine on those portions of the original chime as they only ding one bell and not the motor. So those get wired into the original transformer and directly to the chime. Rear and side door chimes are single solenoid and single strike tones so no problemo.

I didn't make any drawings or schematics as they make no sense without knowing the idiosyncrasies of the camera and the mystery puck. Once you grok the puck, you got the solution.