WE 653 works, but interferes with home alarm

[Tim Mc]

I have an interesting problem.  My Western Electric 653 wall phone will dial out, ring, and receive calls just fine, but after using the phone for 30 seconds to a few minutes, the house alarm will go into an error/fault status, complete with an annoying beep.  The call will continue to stay active.  The home alarm is designed to seize the phone line in case of trouble, so I'm assuming that it no longer sees the line available when I use the 653.  The problem is variable and trips the alarm after going off-hook for 1 minute or 3.  There are no issues when on-hook and using other phones, only when current is flowing through this one.  The problem occurs regardless of the house jack used.

I've swapped out the 5H dial, the talk condenser, and the 101A coil with no change.  I've disconnected the ringer and its condenser with no change.  Since the 653 has a 101A coil, 5H dial, HA1 receiver and F1 'bulldog' transmitter, last night I rewired the phone to be exactly like a 302.  I wired the HA1 and F1 to the coil and the dial as if it were an F1 handset, tying "R" on the coil to one side of both elements, the white receiver lead to the 5H "W", and the black transmitter lead directly to the 5H "BK:.  (That gives me the idea to eliminate the receiver, transmitter and their wires by temporarily wiring in a good F1 and handset cord directly to the coil and dial.)

Anyway, bench testing appeared to work great, however at some point between placing everything back together and mounting it back on the wall the problem resurfaced.  I might add that a few of the original soldered spade terminals were really flaky and on their last few copper strands of wire, so those were snipped and replaced with new crimp spades.

I suspect that it's the 1930's-era wiring harness that connects the hookswitch, dial, and terminal strip.  As much as I wanted to keep the phone original, I'd rather have it work 100%.  So, I'm thinking of replacing the original twine-laced wire harness with new conductors.  Instead of soldering new leads to the hookswitch pile-up I might see if I have some screw terminals from a 202 pile-up to replace the soldered plates, or make some out of brass strip.

Is there any history on the 653s having wire harness issues?  Anything I might have missed before I overhaul the wiring?

Thanks!

Tim

[dsk]

What is happening if you put a resistor in series with the phone (in series with the transmitter) a suitable values should be 100-220 ohms.

dsk

[Phonesrfun]

I am wondering if the alarm is set up to have all phones to the house wired to a jack at the output of the alarm.  Perhaps you have the 653 wired in parallel with the input to the alarm panel, rather than "downstream"  In other words it may not be the 653's fault at all.

Some higher end alarm panels continuously monitor the phone line since the phone line is the alarm's only way of communicating with the alarm monitoring company or the outside world.  Those alarms are designed to have the phone lines wired after the alarm so that if there is an intrusion or a fire while someone is on the phone, it can momentarily cut off the phone conversation, seize dial tone, then proceed to dial out.  The alarm panel has to have full control of the line to do that.

If you wire a phone at the input to the alarm panel and it senses that the phone is off the hook where it cannot control the line, it may give a fault.

Do you have other phones connected in the house, and if so, are they connected to an output jack on the alarm panel.

If so, you should connect the 653 that way.

This is just a hunch, but see if that may be the case.  The alarm panel or the instructions that came with it may have directions for connecting other phones to the line.

[dsk]

The reason for my question about putting in a resistor are based on my alarm system. If the voltage drops too much, the alarm panel starts beeping after a short time. This does not happen when I use a regular telephone, with a normal voltage drop.  If I remove or short the connection  the alarm warns me. I have not been measuring how lo voltage it accepts.

dsk

[Phonesrfun]

Good point, dsk.  The 653 might present a lower resistance than a more modern phone.

[Tim Mc]

Thanks guys!  You've given me some stuff to consider.  The alarm is wired in front of all of the house jacks in order to seize the line, so all jacks are downstream.  All other old phones work fine from this jack and the issue follows the 653 when testing from other jacks.  A voltage drop may be the culprit since I suspect there's a drop in resistance going on somewhere. 

It's basically a wall-mounted 302 right now, so the only thing left to eliminate is the bulldog transmitter, wire harness and hook switch/terminal strip assembly.  I will wire up an F1 handset and bypass the transmitter stuff.  If that doesn't work, I may bypass the old wiring harness and hook switch with some new wiring to see if that works.  If not, then may add a resistor to the transmitter.

As I recall, the phone worked fine on the bench while the base and cover were getting powdercoated.  That's why I suspect something is going on with the wiring now that it's reinstalled in the cover.

[Phonesrfun]

One thing to consider is the fact that the 653, like the 302, shorts out the line during dial wind-up and during during the "on" parts of dial pulsing. 


Does this fault situation ever happen after just answering an incoming call, or when going off hook and not dialing?  If it doesn't fault when you don't dial then the dial shorting could be the culprit.  The phone was designed that way to optimize dialing in the old days of mechanical switching.   If that is the case, the alarm might see the dead short going on during dialing, and after a while issue a fault.  Again, if that is the case, you could make one slight change to wire it like a 202.  There is a red/slate wire that goes between "R" on the dial and "L1".  You could move the end that connects to "L1" to terminal "R" on the induction coil.


That way, the transmitter is still shorted out during dialing, but the primary side of the induction coil is still in the circuit, leaving some resistance.  If that doesn't work, try dsk's suggestion of a 100 or 220 ohm resistor in series with the phone, or just try the resistor to begin with if you don't want to make changes to the way its wired.

[unbeldi]

A "bulldog" transmitter contains an F1 element, the same as in the F1 handset on a 302.  Did you test a 302 on the line?  The only electrical difference between a 302 and a 653 is the receiver, and that is such a minor difference in impedance that it's not worth troubleshooting, since it isn't even in the direct local loop. [sorry mental collapse, you did mention that you had an HA1/706 already]

Which suffix-type of the 653 is yours?  653A ? 

[Tim Mc]

I believe it was a 653-AT, and I managed to get it fixed last night.  I replaced the old wiring harness between the base and front cover and haven't had any alarm issues since.  It's not original, but I wanted this phone to be a daily driver in the kitchen, so I'll live with it.  I used some pre-terminated contact plates from a junk Trimline for the hook switch pile-up, replacing the hard-wired soldered plates.  It took a little while to get the pile-up reassembled, but it works fine and the spade connectors saved me soldering time.  I've attached a diagram of how it's wired now.