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Motorola wireless phone losing base link

Hello Folks,

It happened for the second time: After brief power outages a digital cordless phone (Motorola MD450 series) has lost its base station contact. When it does that it will display "out of range" even while cradled on its base.

Any idea what might cause this?

We do not keep batteries in the base but according to the info that came with it these are only meant to keep the base talking during a power outage. They certainly do not keep up the station ID since I can program it, unplug it, carry it to another location and upon plugging it in the phone will work fine. It seems as if this phone or its base do not like brief power outages.

Regards, Joerg

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Reply to
Joerg
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Hello Ken,

Could be. Although all the programmable settings are in the handset and that doesn't need to do a reset since it's buffered by its battery. Maybe there is something in the base that gets confused. That would be a real disappointment though, considering that it is from Motorola.

Last time I tried to fix a reset I found that it was all under a huge blob of tar, including many of the discretes.

Regards, Joerg

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Reply to
Joerg

ah, the good old days

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martin

Reply to
martin griffith

I had a Panasonic which did the same thing. I called their tech support and was given a procedure to fix the problem. The "fix" involves removing the battery from the handset, unplugging BOTH the phone line and power source from the base. You then wait about two minutes, and reconnect things in a very specific order.

This does the job! I can never recall the order of reconnections but wrote it down in the manual. Chances are this will fix your Motorola as well as I suspect most of these phones share some circuitry and/or chips.

Hope this helps. Robert

Reply to
GrandPaBobby

Sounds like it does a dirty reset. What do you do to fix it?

Cheers.

Ken

Reply to
Ken Taylor

Hello Robert,

This is also what I tried and basically how I was able to re-sync at all. But it only lasted until the next power glitch.

Somehow this all sounds like poor engineering. Kids learn all that high-level math at college but I bet most of them don't have the foggiest idea what a watchdog timer is, let alone using one to recover from hanging due to a dirty reset or brown-out.

In fact, many times when I looked at code I found the watchdog timer was disabled. That's like not having one.

Regards, Joerg

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Reply to
Joerg

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