There's a lot of text concerning specific technical issues, so I have only included an extract of what I think is most interesting in terms of this thread and the use of T10 in the coastal defence (feel free to ask if interested in the omitted details - due to the format and condition of the report, I'm not gonna bother scanning this though). Red text = My comments/notes.
The development of TX:
Torpedo course control during the run has appeared desireable for a very long time and suggestions for obtaining this control have ranged from the towing of a rowing boat by the torpedo, so that a man could be carried who would adjust the course by means of ropes, to the most advanced forms of wire-less control.
The control channel utilized for the TX, consisting of wire which is unrolled from a container in the torpedo, was first suggested by the firm of Siemens & Halsko towards the end of the 1914-18 war.
In 1942, Siemens & Halsko were commisioned by the admiralty to construct roll-controlled gear, but the first models (oil hydraulic), were not satisfactory. This lead to trials with electric gear (electric Pavian), which included both roll and course control, thus making the TX possible. At the same time, consideration was given to location of the torpedo during its run, and it was decided to make it surface during the day time and provide it with a lamp for use at night. A number of preliminary trials were also carried out from E-boats to test different types of wire and transmission gear. It had been hoped to use normal telephone gear for command transmissions and receptions, but trias showed that:
(a) transmissions could not be carried out with sufficient speed so that the turning circle would be excessively large, and
(b) the receiver gear was so much affected by shock that commands could not be carried out sucessfully.
The problem, however, was solved by the use of relay circuits for both transmitter and receiver, which made it possible to transmit commands succesfully at speeds up to five pr. second (this corresponds to the command-frequency used in norwegian post-war wire guidance modified G7a's).
I have omitted the most of the following description, but here's a short summary:
- Transmitted pulses draw about 5mA from the 120V transmitter power-supply.
The receiver draw about 7A from the 30V main torpedo battery.
4 type of commands could be given: Depth, lamp on/off, port and starboard steering.
The wire-type chosen was a 0,3mm steel wire with "Protodur" insulation.
The wire was not spun in a reel, but as a ball kept loose in a canister.
The wire-canister in the torpedo had a capacity of 5000m.
There was some problems concerned with shots over 4000m distance, decided to be caused by the high restiance in the wire, as well as a high capacity between the wire and the sea-water (electrical ground) screwing up the shape of the transmitted pulses. Measures was taken to improve the shape of the pulses, and they succeeded in such way that firings could be made up to 10000m distance (using a 5000m wire at the transmitter end in addition to the wire in the torpedo itself).
The following variants of the T10 was developed:
Preliminary model (no designation given in the report): Used a rotary transformer attached to the gyroscope for course control.
Gerät 43a: Had both roll- and course control. The rotary transformer was replaced by a bridge-control and bridge providing electrical stabilization and rudder-control. Each course-control command produced a 2 degree change in course (post-war wire-guidance modificated norwegian G7a could be controlled by steps of 1 degree). This variant proved to be very reliable but was not put into production due to the lack of manufacturing facilities.
Gerät 43d: The electrical stabilization and rudder control was replaced by a "specht" (a device consisting of 3 solenoids). The specht would disconnect the gyroscope on first course-command received, after that the rudder could only be kept in full port, full starboard or center posistion. Disadvantage: No gyroscope control of the course, ie the torpedo had to be brought to the surface for visual control. Advantage: Easy stering and the torpedo could be set to circle. This was the variant put in production for the shore-defence of France, Denmark and Germany (this may indicate no "Spinnebattery" in Norway, but on the other hand: Batteries have been confirmed in Holland).
Gerät 43c: This variant was a result of the disadvantages of the ruddercontroll from 43d, and was similar to 43a but without roll-control. Only a few trial-models were built, but as with 43a they proved very successful.
Gerät 43cp: This was a variant utilizing a new gyroscope developed by TVA Eckernförde at the same time as 43c and 43d was being tested. The gyroscope could be continuously rotated in addition to having a base that could be adjusted. The base could be adjusted in steps of 2 degrees by a gyro-setting gear, so a similar function as the 43a could be obtained with pneumatic control. Electrical stabilization was not included.
As the gerät 43d, 43c and 43cp had no roll-control, a further variant was developed, comprising a bayonet-shaped vane projected from the torpedo on the roll-axis after launch. This proved quite successful, but it was never fitted to production models.
All torpedovariants were tested by means of firing from traditional tubes, as well as rafts and shore-based batteries. Shots were also made from E-boats, where both torpedo and boat each had a wire-spool, so that the boat was free to manoever after launch (ie the same practise as with modern wire-guided torpedoes as well). Trials were still going on at the end of the war.