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Jeff Liebermann Jeff Liebermann is offline
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Default Why would a DECT Panasonic cordless phone keep losing the wireless link?

On Tue, 7 Jan 2014 04:28:02 +0000 (UTC), Danny D'Amico
wrote:

Any idea why fully-charged DECT Panasonic cordless phones would
keep losing their wireless link lately?
http://farm4.staticflickr.com/3720/1...84d957e3_o.gif


Since it happens with multiple handsets, it's a fair assumption that
all of the handsets did not simultaneously fail. Therefore, whatever
is wrong is at the base unit.

They're not at all far (fifteen feet) from the base and, this
loss of signal only started happening about a year ago (the phone
is probably about three or four years old).


Clue. The transmit power of the base is only about 10 mw of RF. It
doesn't take much to ruin that. I suggest you open up the base unit,
and see if there's anything amiss inside. Look for loose screws,
corroded connections, bad connectors, critters, liquid spill residue,
mechanical damage, cracked PCB, bad solder connections, bad crimps,
and a bad standby battery. The last is a bit problematic as I don't
know if that model uses a battery to retain the settings and messages,
or if it uses flash ram. If you find a battery, test it. If not,
don't worry about it. Also, if it uses the same charger as the remote
chargers, try swapping the charger. If you only have one charger,
measure the voltage under load or just replace it.

What frustrates me is the lack of debugging techniques.


These days, everything is throw away and few devices are made to be
repaired. If you can find a schematic, it will be both a bonus and a
miracle.

Reconnecting the phone to the charger doesn't change anything;
nor does placing each of the handsets back into the mother phone
to reinitialize them.


Only one charging base?

Here's the DECT Panasonic KX-TG6441 phone & handsets:
http://farm4.staticflickr.com/3779/1...40a29bee_o.gif

Here's the model number plate:
http://farm6.staticflickr.com/5539/1...f2dc22f0_o.gif

Googling for that error message, I see it's pretty common; but
I already tried the little that Panasonic suggests:
http://eng-na.faq.panasonic.com/app/...should-i-do%3F

The outlet is working fine; the phone works fine from the base;
it's just the handsets that keep losing their wireless connection.

Anyone else resolve this problem before?


Yes, but not on a Panasonic phone. I think it was a Uniden. It
turned out to be corrosion residue caused by an unreported milk shake
spill several months previously. The outside had been wiped clean,
but the inside was a mess. On an other phone, it was a loose screw
and lug to the antenna wire causing an intermittent antenna
connection.

Any debugging hints?


Tear it apart and look inside.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558