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Panasonic KX-T2365A Phone, to 2 Wire..

Need to convert this Phone from 3 wire to 2..

Any one have any clues or a Schematic..

Its only the Ring circuit that needs to be change..
 
A

Arfa Daily

Jan 1, 1970
0
Need to convert this Phone from 3 wire to 2..

Any one have any clues or a Schematic..

Its only the Ring circuit that needs to be change..

A cap fom the ring return to the 'B' leg should do it - that's all that's in
a standard UK master socket for ring purposes. I can't remember the value
without looking, but it's only fairly small - 0.22uF or something along
those lines

Arfa
 
D

Don Hills

Jan 1, 1970
0
Need to convert this Phone from 3 wire to 2..

Any one have any clues or a Schematic..

Its only the Ring circuit that needs to be change..

Oh come on Roger, you say you were the telecommunications guru at Databank
for many years, you should know the answer to this one?

Connect the white wire from the phone to one of the incoming curcuit wires,
and the blue and red wires to the other incoming circuit wire. If you get
continuous "off hook", you'll have to put a 1 microfarad 250VAC capacitor in
series with the blue wire. If the phone has other than a red/blue/white/green
cord, get back to us- there are a couple of different variations.
 
M

Mark Robinson

Jan 1, 1970
0
Don said:
Oh come on Roger, you say you were the telecommunications guru at Databank
for many years, you should know the answer to this one?

Connect the white wire from the phone to one of the incoming curcuit wires,
and the blue and red wires to the other incoming circuit wire. If you get
continuous "off hook", you'll have to put a 1 microfarad 250VAC capacitor in
series with the blue wire. If the phone has other than a red/blue/white/green
cord, get back to us- there are a couple of different variations.

DON'T CUT THE BLUE W *BANG!* (obligatory ~$^&*!@#NO CARRIER)
 
Oh come on Roger, you say you were the telecommunications guru at Databank
for many years, you should know the answer to this one?

Connect the white wire from the phone to one of the incoming curcuit wires,
and the blue and red wires to the other incoming circuit wire. If you get
continuous "off hook", you'll have to put a 1 microfarad 250VAC capacitor in
series with the blue wire. If the phone has other than a red/blue/white/green
cord, get back to us- there are a couple of different variations.



I am referring to Inside the Phone, it uses a BA8205 Ring IC, I think I
have found some pads to fit the 1UF, but I think that the 1 K resistor need to
be changed as well, the ROHM file shows a 6.2k..

The other problem is trying to find a Small PC mount 1uf 250AC cap that
will fit onto the board..
 
J

Jo

Jan 1, 1970
0
Need to convert this Phone from 3 wire to 2..

Any one have any clues or a Schematic..

Its only the Ring circuit that needs to be change..
question is why? Do you not want it to ring? assuming you want it on 1 pair
...remove all wires except red and green or pins 3 and 4.

The original query is not precise enough.
 
D

Don Hills

Jan 1, 1970
0
I am referring to Inside the Phone, it uses a BA8205 Ring IC, I think I
have found some pads to fit the 1UF, but I think that the 1 K resistor need to
be changed as well, the ROHM file shows a 6.2k..

The other problem is trying to find a Small PC mount 1uf 250AC cap that
will fit onto the board..

You will likely find that a smaller value cap will work just fine. The 1uF
value is for the full REN - to run the maximum allowed ringer loading on the
circuit. Most electronic ringer phones have a low REN, so should work
fine with a lower value capacitor. Telecom's maximum REN (or RAL) is 5, so
if the phone has a REN (stated on the Telepermit label) of, for example,
0.5, then a 0.1 uf capacitor will be fine. Leave the resistor alone,
assuming it is in series with the blue wire coming into the phone it is the
right value as determined by Panasonic.
 
question is why? Do you not want it to ring? assuming you want it on 1 pair
..remove all wires except red and green or pins 3 and 4.

The original query is not precise enough.



As its connected to a 2 wire answer machine it does not Ring, as its a NZ
model setup or 3 wires..
 
A

Arfa Daily

Jan 1, 1970
0
As its connected to a 2 wire answer machine it does not Ring, as its a NZ
model setup or 3 wires..
Why not just connect the phone in parallel with the TAM via a two way
splitter ? That way, the TAM will be happy on its two wires, and the phone
on its three.

Arfa
 
J

Jasen Betts

Jan 1, 1970
0
question is why? Do you not want it to ring? assuming you want it on 1 pair
..remove all wires except red and green or pins 3 and 4.

most new installs are 2 wire. old phones are 3-wire and won't ring on a
2-wire setup.

Bye.
Jasen
 
You will likely find that a smaller value cap will work just fine. The 1uF
value is for the full REN - to run the maximum allowed ringer loading on the
circuit. Most electronic ringer phones have a low REN, so should work
fine with a lower value capacitor. Telecom's maximum REN (or RAL) is 5, so
if the phone has a REN (stated on the Telepermit label) of, for example,
0.5, then a 0.1 uf capacitor will be fine. Leave the resistor alone,
assuming it is in series with the blue wire coming into the phone it is the
right value as determined by Panasonic.



All the Caps that are fitted to UK and NZ Master sockets are rated 250V DC not
AC from what I can see from the markings on the Caps.

The Listed RAL for this phone is 2.4


This is a Large type desk or Wall mounted Speaker phone with 28 speed dial
buttons and a LCD display, clock, call time and phone numbers, with a battery
backup, a full user manual is on the NZ Panasonic web site.



The Ring voltage is fed via the 1K resistor, to a bridge of diodes, this is
smoothed and voltage limited to feed the VCC of the BA8205 Ring IC, ie
the supply voltage to the ring IC..
 
J

Jo

Jan 1, 1970
0
Jasen Betts said:
most new installs are 2 wire. old phones are 3-wire and won't ring on a
2-wire setup.

Bye.
Jasen

That particular phone isnt THAT old, the answer is reasonably simple, just
plug it in. The talk circuit will be unaffected but the ringer wont have
power.

Good phones though, I have one in front of me which I use with a headset.
Cost a very large sum in its day.
 
A

Arfa Daily

Jan 1, 1970
0
Yes but far to messy
OK then, I'm guessing that the TAM is connected to the wall via a 2 wire
lead, terminated at the equipment end in a 4 way Western Electric jack. Swap
it for a standard 4 wire lead, then just wire the ring return lead from the
( previously unused ) pin of the 4 way input jack, to the corresponding pin
on the output jack for the phone. You then have the same scenario, without
having both leads going back to a splitter, and without having to graft caps
into the phone, although I still think that this would be the easiest way to
do it. I have put caps in on a number of occasions, to make three wire
phones ring on a two wire circuit. I can't understand why everyone's getting
so complicated with this - it's hardly rocket science ...

Arfa
 
D

d

Jan 1, 1970
0
most new installs are 2 wire. old phones are 3-wire and won't ring on a
2-wire setup.


Yes they will.

In the two wire setup, all the sockets are masters, with a cap between
pins 2 & 3.

In the old three wire system, there was only a single master socket
witch had the cap, resistor between pins 2 & 3, which provided ringing
over the third wire.

The ringing in still on pin 3, it's just diverted off in every socket
now.

Makes no difference to the phone plugged into it where it happens.

D.
 
OK then, I'm guessing that the TAM is connected to the wall via a 2 wire
lead, terminated at the equipment end in a 4 way Western Electric jack. Swap
it for a standard 4 wire lead, then just wire the ring return lead from the
( previously unused ) pin of the 4 way input jack, to the corresponding pin
on the output jack for the phone. You then have the same scenario, without
having both leads going back to a splitter, and without having to graft caps
into the phone, although I still think that this would be the easiest way to
do it. I have put caps in on a number of occasions, to make three wire
phones ring on a two wire circuit. I can't understand why everyone's getting
so complicated with this - it's hardly rocket science ...

Arfa



TAM has only 2 pins fitted..
 
R

Rebel

Jan 1, 1970
0
d said:
Yes they will


Balls we have both in this house and two phonelines coming in. The older
phones will not work on the second line but will on the first. The later
phones will work on both ....ringing that is they work fine otherwise
 
D

d

Jan 1, 1970
0
Need to convert this Phone from 3 wire to 2..

Any one have any clues or a Schematic..

Its only the Ring circuit that needs to be change..


Ummm zipdisk,

All you SHOULD need to do, is plug it into a master socket with a cap in
it.

That will do the 3rd wire splitting for you.

Am I missing something?

D.
 
D

d

Jan 1, 1970
0
Balls we have both in this house and two phonelines coming in. The older
phones will not work on the second line but will on the first. The later
phones will work on both ....ringing that is they work fine otherwise


Yes, and if you open the socket up, you'll find that you've incorrectly
used a secondary socket. If you replace it with the CORRECT socket,
your fault will be rectified.

Amateurs. Sigh.

D.
 
C

Colinco

Jan 1, 1970
0
d said:
Ummm zipdisk,

All you SHOULD need to do, is plug it into a master socket with a cap in
it.

That will do the 3rd wire splitting for you.

Am I missing something?

D.

Master jacks are years old likely to be faulty by now. Master and
Secondary replaced by 1 type labelled "2" that provided a ringing
capacitor but no 3 wire. Latest news is that a newer type again may not
have the capacitor. Perhaps this has happened already.
http://www.telepermit.co.nz/nl158.html#sec2
 
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