In Ring’s documentation regarding the need for a resistor, they state the following:
“In addition to the equipment included in your Ring Video Doorbell box, You will need to purchase an electronic resistor. A resistor is REQUIRED in place of a mechanical or electronic doorbell kit for this alternate configuration to work successfully.”
There is a serious flaw in this logic. I am an electronics professional, and I totally understand this statement. It MIGHT be true if you didn’t instruct users to bypass the resistance on an existing mechanical chime by installing a jumper wire to bridge the resistance. When that is done, any resistance that exists between the two bridged terminals is negated because the full current will follow the path of least resistance and go through the jumper wire. When you install that jumper you have shorted any resistance. Therefore it is the same as wiring the doorbell directly to the transformer with no resistor.