Technology and Operations  
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Re: RE: Lerche
Posted by: Natter ()
Date: August 27, 2011 03:51PM

I have som info (including electrical diagrams, waveforms etc.) based on interviews of the german scientific staff after the war by the allied forces.


SuperKraut Wrote:
-------------------------------------------------------
> The signal had to be analog since there was no
> mobile digital technology at the time. Considering
> what Lerche did, the wire must have carried the
> sound, instructions for moving the sensor head and
> instructions for moving the rudder. The only way
> to do that is by multiplexing several analog
> signals, a well known telephone technology at the
> time.

This is correct.

> There should be quite a bit of information on
> Lerche in Roessler's book on German torpedoes
> which I have been looking for for over a year. It
> is out of print and the only edition was a few
> thousand copies.

My copy was printed in 2005, so I guess there's been a new edition since the original one? Anyway: It has a 3 pages on the LERCHE, with a couple of illustrations.


Don Baker Wrote:
-------------------------------------------------------
> Do you have any information on the characteristics
> of the signals being carried by the wire - that is
> - did the wire carry analog information back from
> the torpedo array to the sub - what kind of
> bandwidth was required? Again - what was the
> nature of the signals sent from the sub to the

The Lerche cable was made of a 0,45mm copper-cablewith 1,35mm insulation (igelite).
The following was transmitted to/from the torpedo:
a) DC steering signals
b) Control signal (200-300Hz)
c) Pilot signal (29kHz)
d) Acoustic signal (34,5kHz)


> torpedo? Was any kind of multiplexing used?
Yes, as answred bu SuperKraut above.

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Subject Written By Posted
wire guidance in late german WWII torpedoes? Johan Fredin 08/15/2000 06:39PM
RE: wire guidance in late german WWII torpedoes? joe brandt 08/16/2000 12:21AM
RE: wire guidance in late german WWII torpedoes? Johan Fredin 08/20/2000 10:36PM
RE: wire guidance in late german WWII torpedoes? joe brandt 08/21/2000 12:27AM
Lerche SuperKraut 08/21/2000 10:26AM
RE: Lerche Johan Fredin 08/21/2000 01:02PM
Chicken and egg SuperKraut 08/24/2000 08:52AM
Re: RE: wire guidance in late german WWII torpedoes? Natter 07/04/2018 11:29AM
RE: Lerche joe brandt 08/21/2000 08:28PM
Lerche technology. SuperKraut 08/24/2000 07:58AM
RE: wire guidance in late german WWII torpedoes? Garth 08/21/2000 05:18AM
RE: Lerche Don Baker 08/22/2000 08:34PM
RE: Lerche SuperKraut 08/24/2000 07:48AM
Re: RE: Lerche Natter 08/27/2011 03:51PM


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