Lets talk lichtsprecher....

[fieldgear]

Hi again

The cables are OK. I have tested them when I did the voltage test. The mics are the standard press type. "Feind Hort Mit!"

I will test the valve by swapping it with another. Otherwise I can only test the filament is OK with a multimeter.

Ill do this when I get home tonight.

Best,>Rob

[Val]

however the light output from head B has become a little weak.

Was the light before OK? What version heads do you have and is the lamp 2.4 or 4.8 volt?

[fieldgear]

Hi Val

The lights were OK (& still are, just a bit dim) & are 2.4V. They work fine just something has either become loose or is dirty, or the battery is dying. I am sure I can sort it out.
The heads are the later style with mounts for a tripod. Both 1940 dated with Zeiss logo.

Best,>>Rob

[Funksammler]

Lichtsprecher accessories

The Lichtsprechgeraet requires some specific cables and accessories, so hopefully this will address some of the queries.

There are two types of Lichtsprechgeraet, the older type uses a 4,8 Volt lamp in the optical head while the later type uses a 2,4 Volt lamp in the optical head.

- The earlier type needed to separate low voltage supppies, a 4,8 Volt battery to supply the lamp and a 2V battery to supply the valve filaments in the amplifier. The old type amplifier had a fixed HV supply cable, with the anode battery stored in the top box directly next to the amplifier. So the old type only has one loose supply cable with plug. Because of the two separate batteries, this cable had four leads, a "+" and a "-" for each battery. The "-" leads are connected together in the plug and are connected to the chassis or earth of the Lichtsprecher.

Here are the typcial batteries used with the old model Lichtsprechgeraet:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06193_zpsb58ffb15.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06193_zpsb58ffb15.jpg" border="0" alt=" photo DSC06193_zpsb58ffb15.jpg"/></a>

The old type battery cable has four leads:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06190_zps4264b3d7.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06190_zps4264b3d7.jpg" border="0" alt=" photo DSC06190_zps4264b3d7.jpg"/></a>

- Later model Lichtsprechers used a 2,4 Volt lamp and a single 2,4 Volt Power supply. The 2 Volt filament voltage was made by a 5,3 Ohm series resistance hidden in the plug of the supply cable. Because the equipment now only needed one low voltage supply, there was space to move the HV battery to the bottom box of the Lichtsprechgeraet. This did however necessitate an extra HV connection cable.

Here is the 2,4 Volt battery typically used with later type Lichtsprechgeraet:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06194_zps29ce7fcb.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06194_zps29ce7fcb.jpg" border="0" alt=" photo DSC06194_zps29ce7fcb.jpg"/></a>

The Lichsprecher now required two supply cables, a two lead LV cable connected to the 2,4 Volt battery and a four lead HV cable connected to the Anode battery (Note that the two cables are tied together):

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06189_zps15499eb1.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06189_zps15499eb1.jpg" border="0" alt=" photo DSC06189_zps15499eb1.jpg"/></a>

You can operate the old type amplifier with a new type optical head (like I am doing); in this case you need can use a "new" type two-lead battery cable with a series resistance to power the set.

- The lamps in both old and new type Lichtsprechers could be manually operated to transmit Morse code. a special "Taster" was supplied with the Lichtsprechers:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06186_zpsdc37c443.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06186_zpsdc37c443.jpg" border="0" alt=" photo DSC06186_zpsdc37c443.jpg"/></a>

The thumb switch would switch the power supply directly to the lamp, because of the relatively long afterglow of the lamps used in the Lichtsprecher, only very slow Morse code could be given. I suppose the "Taster" was mainly used as an aid to set up and align the optics and in an emergency if one of the Lichtsprecher amplifiers failed. It is certainly not very suited as a replacement for a "Blinkgeraet".

- The Lichtsprecher requires a relatively low-Ohm carbon microphone. The Lichtsprechers were supplied with a specific microphone which holds a standard FF33 micorphone unit:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06187_zps617db3b4.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06187_zps617db3b4.jpg" border="0" alt=" photo DSC06187_zps617db3b4.jpg"/></a>

As an alternative an old type stick microphone can be used:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06188_zps7196af56.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06188_zps7196af56.jpg" border="0" alt=" photo DSC06188_zps7196af56.jpg"/></a>

Later types of microphone like the Hmf.b (The classic "Feind hoert mit!" microphone with a two pin plug) are less effective. I tried these and it kind of works, but the signal is significantly weaker. So I guess that one of the problems you are having is a weak microphone signal. You probably have to rope in the misses to speak loudly into the Hmf.b to give you a better chance of hearing anything on the receiving end.

This should not hold you back because you can rig up a FF33 handset as an alternative.

regards,

Funksammler

[Val]

Thanks, Funksammler. I imagine that this Blinktaster was also very uncomfortable to operate...

Btw, Techmili has one incomplete head on the offer page.

http://www.techmili.com/Echanges/Echanges.htm

[Funksammler]

I have now been playing with the Lichtsprechers for a few days and interestingly they are getting better and better. To start with things were extremely critical and I needed to crank up the volume to the maximum to hear the signal on the other side. Right now it is ten times louder and it seems much easier to align. I think that due to the recent use, the electromagnetic modulators have become unstuck and are vibrating more freely. This gives a much stronger modulatation and louder noise in the receiver.

In one of the sets, I am now getting significant feedback from the microphone. I traced this to the (non original) connection cable, which seem to have a noticable capacitive coupling between the transmission and reception signal. I suspect that the original cable uses a shielded wire for the audio reception signal. I think this is also the cause of the whistling I noticed earlier in field telephone mode. I did not notice the microphone feedback at the start of my experiments, but I have the impression that the amplifier has also become more sensitive. More difficult the explain, but perhaps due to the recent use the various connectors and volume potentiometer have been cleaned up a bit, lowering transfer resistance and increasing signal strength.

In any case: with exercise, the Lichtsprechers get better and better!

regards,

Funksammler

[Val]

I have now been playing with the Lichtsprechers for a few days and interestingly they are getting better and better.

Interesting...there could be also a cold soldering/joint, now when the whole thing is properly heated up, the moisture is gone and the contact is better...

Btw, was there as official code when and how was the different filters (clear light, red, infrared) used?

[Funksammler]

Btw, was there as official code when and how was the different filters (clear light, red, infrared) used?

I don't have the manual handy, but I suspect it contains a table listing ranges and conditions in which the various settings could be used. I now have the original Dienstvorschrift D88/1 for the M-Blink and this contains a similar table with guidance on settings and which lightbulb to use. The idea is that the light output is kept as small as possible. I guess they would use visible light to align the set, switching to red during the day, infrared during the night

Regards,

Funksammler

[Tornfuté]

About this steel box with white marking 4,8 NC it's the transport box with a 90 degres adaptor
in which battery is pluged ,
in D877/2 the batteries are described , and people can seen lonely battery strapped, i never
see in lichtsprecher notice a view of a box battery , did you get informations that it was effectly
use with lichtsprecher ?
I own the same complete battery in steelbox , they are different marks , no 4,8 nc5 on lid
but a WaA 763 , also inside a code : cme = wichmann Berlin optical instrument factory
my batteries are made in 1942 by DEAC deutsche edison akumulator fabriek
about your 2,4 NC battery i never see one like this , it must be equivalent of the 2B19
but nickel cadnium 2,4 NC 19 ??
strange that they are no notice about the 2,4 volts version lichtsprecher , as it's not a late war design , all notices were destroyed ?
did somebody has information about the other lichtsprecher 250/13 , i only has seen a picture of a norvegian collector who own one ,it's an improved version ,
about your sets i guess it's the sets used along Beatrix canal in 1983 , no wonder if they still works , when powering them , the capacitors reforms ,and set will works better ,
did you have HDV493/50 ? it handle over accumulators

http://i898.photobucket.com/albums/a...ps379d8cb0.jpg

http://i898.photobucket.com/albums/a...psac162f31.jpg

http://i898.photobucket.com/albums/a...pse90b08a1.jpg

http://i898.photobucket.com/albums/a...ps231f49ca.jpg

http://i898.photobucket.com/albums/a...ps2d4b0825.jpg

pierre

[Funksammler]

About this steel box with white marking 4,8 NC it's the transport box with a 90 degres adaptor
in which battery is pluged ,
in D877/2 the batteries are described , and people can seen lonely battery strapped, i never
see in lichtsprecher notice a view of a box battery , did you get informations that it was effectly
use with lichtsprecher ?
I own the same complete battery in steelbox , they are different marks , no 4,8 nc5 on lid
but a WaA 763 , also inside a code : cme = wichmann Berlin optical instrument factory
my batteries are made in 1942 by DEAC deutsche edison akumulator fabriek
about your 2,4 NC battery i never see one like this , it must be equivalent of the 2B19
but nickel cadnium 2,4 NC 19 ??
strange that they are no notice about the 2,4 volts version lichtsprecher , as it's not a late war design , all notices were destroyed ?
did somebody has information about the other lichtsprecher 250/13 , i only has seen a picture of a norvegian collector who own one ,it's an improved version ,
about your sets i guess it's the sets used along Beatrix canal in 1983 , no wonder if they still works , when powering them , the capacitors reforms ,and set will works better ,
did you have HDV493/50 ? it handle over accumulators

http://i898.photobucket.com/albums/a...ps379d8cb0.jpg

http://i898.photobucket.com/albums/a...psac162f31.jpg

http://i898.photobucket.com/albums/a...pse90b08a1.jpg

http://i898.photobucket.com/albums/a...ps231f49ca.jpg

http://i898.photobucket.com/albums/a...ps2d4b0825.jpg

pierre

Thanks for posting these, another collector sent me some pictures of another example of this "boxed" battery, which is clearly marked 4,8 NC 10 on the outside of the box (mine is marked 4,8 NC .... with the last numbers missing). The marking is a bit confusing, as it is half the size of a 4,8 NC 10, so I would deduct it has half the capacity of the full size battery....

The battery that is inside the box is pictured in the manual of the "early" lichtsprech geraet, without the box. Or at least that is what it appears to be....

This 2,4 Volt battery below is actually the same size as the 2B38:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06194_zps29ce7fcb.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06194_zps29ce7fcb.jpg" border="0" alt=" photo DSC06194_zps29ce7fcb.jpg"/></a>

It was mainly used in the Torn.Fu.k and Torn.Fu.i, but it would fit the battery compartment of the Lichtsprechgeraet. It is roughly twice the size and capacity of the 2,4 NC 28, hence it was called the 2,4 NC 58

regards,

Funksammler

[Funksammler]

Lichtsprechers in the Garden....

Today dawned sunny and dry, so I decided to do the next phase of testing the Lichtsprechers. I found a nice clear line of sight in the garden giving me a distance of about 50 meters. Here is set nr 1 ready to go:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06200_zps36af19f6.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06200_zps36af19f6.jpg" border="0" alt=" photo DSC06200_zps36af19f6.jpg"/></a>

Hre it can be seen between the trees in the back of the garden from the other set:
<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06196_zpsb557f14a.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06196_zpsb557f14a.jpg" border="0" alt=" photo DSC06196_zpsb557f14a.jpg"/></a>


Set nr 2 was installed at the other end of the Garden:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06195_zps18134f93.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06195_zps18134f93.jpg" border="0" alt=" photo DSC06195_zps18134f93.jpg"/></a>

... here is how it looking from set nr 1:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06203_zps307581cb.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06203_zps307581cb.jpg" border="0" alt=" photo DSC06203_zps307581cb.jpg"/></a>

I started by aligning the sets on the "gestreut" setting (gestreut means scattered, the light beam is at it's widest on this setting), after switching to "unsichtbar" (infrared) the adjustment is again very critical with a very clear maximum when the sets align. Because of the low level of the sun, I had to do the fine alignment by ear as the red mark was not visible in the scope.

With the increased distance and with help of the wife I could better test the quality of the modulation. Set nr 1 was set up a bit too loose, giving quite a lot of distorsion, so it needed to be adjusted a bit. Again the modulation grid was not visible due to the low sunshine, so I needed feedback from my wife on the other end of the line. This made the process quite difficult and I am not sure how this would be done at greater distances.

In summery, the sets worked well over the short distance in these bright sunlight conditions on both visible and infrared settings. Alignment was difficult because the aiming marks in the aiming scope were not clearly visible.

It is probably easiest to set up the Lichtsprech Geraete in the dark, when the light and all the indications are clearly visible. When setting up in bright conditions it was probably best to pre-adjust the modulation over a short distance before setting up any long distance links.

A final shot of the amplifier in the test setup:

<a href="http://s672.photobucket.com/user/Funksammler/media/DSC06201_zps2483beb8.jpg.html" target="_blank"><img src="http://i672.photobucket.com/albums/vv86/Funksammler/DSC06201_zps2483beb8.jpg" border="0" alt=" photo DSC06201_zps2483beb8.jpg"/></a>

regards,

Funksammler

[fieldgear]

Hi Funksammler (& all!)

Great to see your sets working!

Ive been following the thread with great interest, & this thread has more info & detail around batteries, leads & microphone than any other resource I am aware of.

I want tio share this site I found recently too. An Admiralty report that runs some 30 pages. The copy is not great, but generally readable. I note he refers to both my own collection site & WHA!

http://www.scribd.com/doc/161571591/...0mm-Photophone


I appreciate the help everyone has given, & I have worked on my sets every night, but am still having issues. I have decided to start again from the beginning, rebuilding my power supplies as currently there seems to be a problem with the voltage holding up. These are electronic so the voltage can be exact, but right now its a bit cobbled together & the battery life seems exceedingly short despite being 4.5Ah.

I have had both sets responding to tubes (50Hz) & to objects passing in front of the cell. However, variables seem to be creeping in. It seems that things that worked now don't etc, so hence the decision to start again from the beginning.

Im on leave from work now so full focus on this project. All I want for Christmas is for these to work!

Best,>>Rob

[Val]

A
I own the same complete battery in steelbox , they are different marks , no 4,8 nc5 on lid
but a WaA 763 , also inside a code : cme = wichmann Berlin optical instrument factory
my batteries are made in 1942 by DEAC deutsche edison akumulator fabriek

Thanks Tornfuté fo the battery images! Merci!

[LA6NCA]

LiSpr80 Light Cell

Hello
I have not been here in a while.
So that you discuss the LiSpr80.
Very interesting ..

Would mention some aspects that I have not written about on my internet site.
Light cells were deffekte.
Had forgotten how I solved the problem, so I had to open a LiSpr80 to see.





When I would get LiSpr80 operative I found that all light detectors were defect.
I therefore had to mount a light transistor.
I drilled a hole and soldered it.




To provide transistor proper working condition I had to install some additional components.
It does not look quite good, but I should have the equipment operational quickly.




1 Improved noise with 100uF from the negative grid voltage (21) to gnd.
2 Node # 18 was converted to constant 12V with zener diode.
3 capacitors 47uF and 3.3uF from node # 18 to gnd.
4 Resistor on 27K supplies power to the transistor from node No. 18
5 Resistor on 100K and 82K supplies power to node no.18.



I make a new LiSpr80 page. Not finished.
http://fykse.dnsalias.com/ww2/LISPR80/

LA6NCA

[Val]

I make a new LiSpr80 page. Not finished.
http://fykse.dnsalias.com/ww2/LISPR80/

Thanks, very interesting notes. Since you already changed photoresistor with the phototransistor, have you thought about substituting the light bulb with the modern power LED on your new head project - so you can test whether you can reach more than 5km?