Anyone know anything about antique telephones? (I hope this is the right
newsgroup for this).
I have a couple of antique crank phones. One is the "large box" phone with
storage space for batteries, and the other is a "small box" phone without
batteries. I want to wire these phones together to make an intercom (not
wired to the phone network).
Inside the phones, there's terminals labelled (in order from top to
bottom) "Line 1" "Gnd" "Line 2" "Cond" and "Cond" (yes, two "COND"
I've searched the net, and found a bunch of wiring diagrams for the
internals of phones. However, I haven't found two crucial things. What
voltage of battery should I be using (I think between 6 and 12 volts), and
exactly what terminals should I wire together on the two phones. If anyone
could e-mail that information to me, I'd be very grateful.
I have done some experimenting. I've found that
- when I connect "line 1" on each phone to "line 2" on the other phone,
and then turn the crank, the bells ring on both phones (as they
- when I hook a 9 volt battery into the system wired this way, I can hear
"crackles" in the earpiece for both phones when they are off-hook.
Again, this makes sense to me. You should hear the same thing in both
phones. The problem is that I'm not getting any sound from the
microphones when wired this way. Is the problem in my wiring? In the
voltage for the batteries? I'm not sure.
- If I wire line 1 and GND on one phone to line 1 and line 2 on the
other phone, then turn the crank while holding the "switchboard button"
(little read button on the side of the phone) down, then the bells
ring on the other phone. Again, that makes sense. The "Switchboard
button" is there to make the switchboard ring to make calls outside
the party line. However, since I don't plan to go through a
switchboard, I can ignore the GND terminal, right?
- I have no idea what the "COND" is for, except that it stands for
"Condensor". I did check with my voltmeter, and it looked like the
battery current was measured between the first "COND" terminal and the
"LINE 1" terminal when the phones were off-hook. Does that mean I should
wire the "COND" terminal into the line somehow?
If anyone can tell me what terminals to wire together, and what voltage
the batteries need to be, I'd be very grateful. I don't get to the
newsgroups very often, so if you could e-mail me that would be great.
Kevin Lowey wrote:
> Anyone know anything about antique telephones? (I hope this is the right
> newsgroup for this).
Sent via Deja.com http://www.deja.com/
Before you buy.
The transmitter and receiver elements may not be in the best of shape
and may need replacement.
The phones would be connected together using a pair of wires, connecting L1 and
L2 of one phone to L1 and L2 of the other phone.
In the large phone (1317 model?), the two terminals for the battery are located
on the ridge of the shelf that the generator sits on.
The smaller set should also have two terminals marked for the batteries. If
this is the 1717 model, these will be marked "SL" on the induction coil
(positive) and "BATT" (negative). The batteries (usually three #6 cells, 1.5V
each) were intended to be placed outside the phone, but if you are using a 9V
transistor battery, there is probably room inside the cabinet.
>I have a couple of antique crank phones. One is the "large box" phone with
>storage space for batteries, and the other is a "small box" phone without
>batteries. I want to wire these phones together to make an intercom
WE20...@aol.com (David Willingham)
> Andrew Emmerson.
Seems like the battery compartment of those old phones was meant to
hold two of those big zinc/carbon cells, the ones that are about 2
or 3 inches diam and 6 or 8 inches long. That equals three volts.
The last time I remember seeing those used was when the kids and
their dads flew their model airplanes in the schoolyard. They were
used to heat the glowplugs to start the engine. Loved that smell
of airplane fuel(!)