The Tischfernprecher 38 was the desk telephone version of the German field telephone FF33. It was primarily used in offices of commissioned officers. It consists of a telephone and a beikasten that is connected to the phone by a 7-conductor cloth covered cord.
The beikasten contains the T30 1.5 volt battery for powering the handset microphone as well as terminals to connect telephone lines, the battery, and an AC bell.
My Tischfernsprecher 38 had a broken wire in the cord, so the cord needed replacing. Since 7-conductor cloth covered cords were unavailable, I ordered an 8-conductor cord from… https://www.oldphoneworks.com/cord-subset-8-condutor-brown.html
I cut the new cord in half, stripped the insulation, drilled the rubber inserts for the phone and beikasten, soldered the wires to the beikasten, heat shrunk tubing, and connected the spade terminals in the phone.
I connected the phone to OB line 9 of my 10-line switchboard. I also connected an AC bell to the “W2” terminals in the beikasten.
WW2 German Field Telephone Equipment 