EE-8 field telephone repair

EE-8 Repair

First, clean dirty contacts, lubricate moving parts.

July 2022 - I learned that a great cleaner for connectors where batteries leaked is vinegar. I very light coating of dielectric grease may be helpful for battery contacts. Find dielectric grease at an auto parts store.

Try removing and reinstalling the mouthpiece and earpiece parts. A staticy sound can be caused by a bad contact anywhere. Clean spade connectors and any washers and nuts with sandpaper for a good connection. Handset wire color coding: the white wire is the receive, the red wire is the common, and the black wire is the transmit.

Sometimes if a crank phone quits working, try cranking backwards a little bit. If the crank mechanism is a little sticky, the retract mechanism may stick in the crank mode, and not revert to talk mode.

Basic checks with an ohm meter and a voltmeter:

No batteries installed:

Resistance measurement from terminal “C” to “Rec” should be about 20 ohms to 50 ohms.

Resistance from “C” to “T + Bat” should be infinity with handset switch not pressed.

Resistance from “C” to “T + Bat” should be about 250 ohm to 750 ohms when handset switch is pressed.

With batteries installed:

Before batteries are installed, the sum of both batteries should be 2.5 to 3.4 volts. The “LB, CB” screw should be turned counterclockwise (anticlockwise).

When batteries are installed, there should be 2.5 to 3.4 volts from terminals “C” to “T + Bat”.

There will be no voltage reading from terminal “C” to “Rec”.

To test the handset -

This works only with WWII and earlier phones, with a carbon (not dynamic) mic or transmit element. See 11-2015 Test note below, too.

1. Mark all handset wires as to where they go.

2. Disconnect the handset from the telephone.

3. Connect a 1.5 volt battery across the C Common, or red) to Rec (receive or white) wires OF THE HANDSET. You should hear a scratchy noise in the receiver. This means the receiver works.

4. If the receiver works, hook up the handset Rec wire (white) to one terminal of a 1.5 or 3 volt volt battery.

5. Hook up the T+Bat wire (Black-Tx) of the handset to the other battery terminal. The common wire is left unconnected.

6. If the press the talk switch and blow, you should hear it in the receiver. If not, you probably have a bad wire or transmit element. If it doesn't work with 1.5 volts, try a 9 volt battery. Don't do this too long, 9 volts is a higher voltage than it was designed for. Three volts is the normal operating voltage.

11-2015 Test note - You can test the handset of an EE-8 without disconnecting the handset -

1. Insure there are no batteries installed in the phone, and nothing connected to the L1 and L2 output.

2. Connect a 1.5 volt battery between the "T+ Bat" terminal, and the "Rec" terminal. Leave the center "C" terminal alone.

3. Press the talk lever on the handset, and blow in the mouthpiece. You should hear it in the receiver.

If you get no reading with the resistance checks, the most likely cause is a bad cord. Remove the mouthpiece, and measure the resistance of the element. It should measure 250 to 750 ohms. Remove the earpiece, and measure the resistance of that element. It should measure 20 to 50 ohms. If those both read in the range listed, it would most likely be the cord or switch. For a replacement handset cord, I use a black computer power cord, as long as you can remove any writing. Some cords are more flexible than others, or a more usable diameter. There is still a possibility that it could be bad contacts, connectors, or other rare problems. If it might be a connector to wire issue, try squeezing each crimp connection with a pliers or vise grips.

To test the magneto cranking voltage, the most reliable way is with a known working phone. A voltmeter (in AC volts position), especially a digital one, may not read at all. As a last resort, put one hand across the L1, L2 terminals and crank. Ouch!

A note from Dag, in Norway (2022): "The gear and bearings of the generator may need some oil, do not use oil that contains silicone, by some reason the contact sets will not like the gases from that oil. If the idea with getting the ringer to ring was for testing any strap between the 2 terminals you marked will do the job, If you use a capacitor there permanent the phone will both draw more ringing current. (Be less sensitive) and you will loose dome of the voice signals."

To test the bell, hook up a known working phone and crank the other phone. If it doesn’t work, it may be a physical adjustment problem. Remove the bottom plate of the phone, with the bell attached, and see what you can figure out.

Parts can be purchased from: http://www.phonesurplus.com/ I have made several purchases from Steve. His prices are very reasonable, and he can do repairs, too.

April 2021 - I was contacted by a person with an EE-8, who wanted to know if there were a way to make the phone ring if there were no phone hooked up to it. Normally, the calling out EE-8 does not ring. What I came up with, that doesn't seem to interfere with normal use, is adding two jumper wires. But-

Steve at phonesurplus has a better way - Adding a 1 ufd, 200volt (minimum) capacitor between the top and bottom lugs on the magneto, where the blue tape is on the picture below. An easier solution than mine, but it might be hard to find a >200 v capacitor.

If you are not handy with tools or soldering, look for a local Repair Cafe or Fix-It Clinic.

I can be contacted at deweyhassig@gmail.com