A few years ago I ran some wires to an buzzer in my basement, to ring when someone pushed my front door bell button. It worked with the existing chime for a year or so, then one day I determined it wasn't working anymore. I checked the obvious ( voltage at the buzzer, verified that the buzzer was good, connections etc...). Eliminating a lot of test in between, I found that when I hook the buzzer wire to the front door terminal on my chime, it works, but then I only get one tone instead of 2 tones for the front door. If I remove the buzzer wire, I get 2 tones as usual for the front. I'm thinking that I need to get a bigger transformer. The existing transformer is at least probably 25 or 30 years old. I'm guessing it's just getting weak with 2 loads on it, and not enough to pull them both correctly. What are some of your thoughts on it. I don't know exactly how many volts the transformer is( guessing 16 volts), but I'm thinking about putting a 24 volt on it and hope that works. Thanks for the input. Steve...

door bells get week up the va on transformer should fix it 40 va works good i had to do it at home too

The doorbell is probably getting stiff and a door bell transformer will usually run only one doorbell, so the buzzer is maxing out the transformer. Get a bigger transformer, but I wouldn't suggest a higher voltage.

You could also parallel another 'matching' transformer next to the original. Or, pick up a 40va.