On Fri, 27 Jan 2012 21:51:55 -0500, "Robert Green"
wrote:

"gregz" wrote in message
...
IGot2P wrote:
On 1/26/2012 3:02 PM, Robert Green wrote:
My neighbor asked me to look at her wireless doorbell, which suddenly
stopped working properly. The buttons still work if you move them
close to
the unit but they no longer work mounted on the outside of the door
frame.
We've replaced the 3 "D" cells in the base unit and the 12V cells in
the two
buttons but still no joy.

12V cells?


Any ideas?

--
Bobby G.



I think that's common, and not cheap.

I'm thinking the sets operate around 400 MHz but doubt if anywhere near
wifi.
I don't know if there is a frequency adjust, but I would suspect the
frequency is off.
They are cheap enough to replace the whole thing.

I spent some time today testing the various frequency setting jumpers with
no joy. Put a huge metal pot over the WiFi hotspot with no joy. While the
doorbell may not be in the 400MHz range, the harmonics from the hotspot
could be strong enough to "step" on the doorbell signal. I've taken home a
dead, water damaged button to look at the circuit board.

Occasionally a little piece of wire extending the antenna helps. The WiFi

That doesn't prove much. It's just a variation on "inadequate range".

I have a radio in my shop which always worked fine. When I started
trying to fix my old computer in the shop, the moitor interfered with
the FM reception on the one stattion I listen to, 88.1FM (so I
swticherd to internet radio, but there are still times I'd rather just
turn on the radio.) Months later I went through a period where the
radio worked fine even when the monitor was on. A few days. Then it
went back the old way, and turning the monitor on when the computer
was running ruined the radio reception. I have no idea yet why
sometimes it works and sometimes it doesn/t

router is unfortunately set up about ten feet away from the doorbell. My
neighbor did not want to turn off the router because it's twitchy to
restart. In fact, I am going to donate one of my old, flea powered UPS's to
her so that it doesn't get locked up when there's a power blip. I think
it's the WiFi unit, but I was surprised that putting it under a big metal
pot had no effect on the doorbell's range.

Doies the pot have to be grounded? I've never understood this, so I'm
not saying it has to be. But there was some reason in the past I
began to think that. .

She has some other wireless gear
in the house so RF interference seems likely. I am going to try to figure
out the frequency of this unit (no FCC ID that I could see) and then we'll
look to buy a unit with a different frequency to see if that works any bette
r. As you point out, they're cheap enough that any more hours spent
debugging this one would be a waste compared to just getting a new one.

--
Bobby G.