Are you going to start at the switch or are you installing a point-to-point line? For this lesson,
the discussion will be about installing a point-to-point telephone. Installation will be from one tree or
post to another. All the work will be outside. Now that you know what needs to be done, start with the
procedures for installing the first instrument on the line.
The telephone set TA-312/PT is a universal telephone. It is used on many guard posts or
point-to-point lines and WD-1( )/TT can be used to install the line. A tree or tall post should be selected
and the telephone installed in a vertical position. Use the strap on the case to wrap around the pole
above the telephone to keep it from slipping down. You will need a piece of WD-1( )/TT to go around
the pole at the bottom of the telephone to keep it from flopping around. Be sure the wire goes through
the lower loop of the carrying case and tie it securely in place.
Now check the selector switch and see that it is set on LB. This is because you will
install two BA-30 or BA-3030s in the battery compartment to provide talk power. Remember, this
telephone has a crank on it to ring the distant end. Since the handset is off the telephone, check to see if
the de-icing screen has been installed. It is only used to keep the operators breath from freezing on the
If the de-icing screen is not required or installed, you must make the adjustment to the
telephone. To install or remove the de-icing screen, unscrew the transmitter cap and look into the cap.
You can use a screwdriver to pry it out gently or you can install one in the cap.
Some units use the off-hook lamp assembly for security reasons. If you have to install
one it is quite simple. Remove the panel screw nearest to the LINE binding posts. Secure the lamp to
the telephone with this screw, keeping the lamp snuggled near the telephone cradle. Run the lead of the
lamp assembly around the retaining brackets and connect its two terminals to the BAT binding post on
You must check the WD-1( )/TT you are going to use. Connect a telephone to each end,
ring it down, and talk on the line. This is the best check you can make.
It is time to connect the WD-1( )/TT. Strip approximately 1 inch of insulation from the
ends of the two wires in the line to be connected. Be sure the wire is clean and there is no residue
remaining. The unit SOP will state whether to keep some insulation on the end of the wire. If not, fold
back the stripped wires about 1/2 inch from the end. Push down one of the LINE 1-2 binding posts.
Insert the bare end of one wire into the binding post slot and release the post. Check to see that the wire
is securely clamped. Repeat the procedure with the other wire, in the other post. Install a tag on the
telephone D-ring and mark it according to your unit SOI to identify the circuit.
Check your work. The telephone is installed, batteries are installed, the selector switch is set to
LB position, de-icing screen is installed, security lamp if needed, and you are connected to the line. Did
you take into consideration what happens to the wire now?