German Hagenuk Ship telephone (Fortress telephone)

[dsk]

This was installed in the tunnels used by the forces when I served in 1983.

dsk

[dsk]

I dont know why, but the ringer capacitor are 2 μF and the ringer was 250 ohms!  500 +500 in parallel.
This caused an enormous REN. when changing the ringer to 1000 ohm with the coils in serial configuration, and adding a 1
μF capacitor in series with the ringer, I came down to a load working on my PAX without reaching a current fooling it to believe I had gone off hook.

I guess I have a load on less than 2 REN now.

My phone has big corrusion problems after 30 years in a damp tunnel.

dsk