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Lectron - Manfred Walter Era

Hartmut Birett's Recollections
Early Research
Günther Stabe's Initial Analysis
June 28th, 2013 Update
June 29th, 2013 Update


The Funktionsmodelle was the most academically ambitious model released in the Lectron product line to date. The model was developed in 1973 by Hartmut Birett. The accompanyinig manual was actually a book published by Diesterweg in 1974 and was written for college/university level students and went into very detailed descriptions of biology functions and how these functions could be illustrated or demonstrated by electronic circuits. Unique to all the Lectron models, a transparent foil could be placed over the drawing schematics to show what individual Lectron blocks were to be used for the experiment. This innovation was also the idea of Mr. Birett.

The Funktionsmodelle was the only model to ship in two separate boxes but with identical nomenclature. There was no marking such as Box 1 of 2 or something similar.

The instruction book was available through regular retail book channels in addition to being included with the model.

Close ups of the individual trays:

The below is a photo proof of the first version of the model layout. This was the photo used in the Funktionsmodelle brochure. Notice the lack of the LEDs in two of the block types.

Like the Physik Experimentell model, it was released to the marketplace between October 1974 and October 1975 (according to published price lists).

Priced in its final appearance in the 1999 price list at 1628 DM (about $990.00), this was the most expensive single model (as opposed to the hybrid Special Laboratory models) to date in the Lectron product line.

The 4 major blocks used ICs and featured TTL logic which required that the blocks use a 5VDC power source. Even the relay block was made in a 5 volt version. The 8170-101 LN300 5VDC power supply was required. There were two versions of two of the major blocks. The first version may have been the prototype and was used for the brochure photographs. The productized second version added LED indicators.

When visiting the RWO in June of 2014, Günther Stabe discovered a small box at the bottom of a larger box which had just a few blocks from the Funktionsmodelle model. There were a couple of 'dummy' blocks which only had the white cover with schematic but had no electronic components on the inside. There were also some complete blocks which are shown immediately below.

Two of the experiments illustrated within the book.

This is another very rare model and I have only seen it appear once on eBay since I began my research in 2012.

This model was discontinued by 2000. Its last appearance was in the February 1st, 1999 price list.

Hartmut Birett's Recollections

One of my research efforts has been to find and converse with as many LECTRON major contributors that I could. After a preliminary search on the Internet using Mr. Birett's name, I came up with a number from a directory. On June 4th, 2015, I called that phone number and a woman answered. My lack of German prevented my being able to speak to Mr. Birett and I was not sure if he was the correct person. I asked my research colleague Günther Stabe to call the number. On June 8th, Günther called the number and success! A 35 minute phone conversation ensued followed up with an email exchange.

Mr. Birett was a prospective teacher for biology and physics when he brought his first LECTRON set, an Egger model. The reader will recall that Egger sold the Lectron between 1966 and late 1967 before Braun took over the brand. The unique flexibility of the Lectron got Mr. Birett to thinking that the LECTRON could be used to better clarify concepts to students for cybernetics and functional models.

He communicated by mail to Mr. Manfred Walter of Lectron, GmbH and thus began their collaboration.

Mr. Birett related to me that money was hard to come by for Mr. Walter even back in 1974. Instead of paying just cash for the development of the Funktionsmodelle model, Mr. Walter traded some equipment to Mr. Birett to satisfy the financial obligation. Mr. Birett still had that equipment when I visited him in December of 2015.

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Earlier Research

The research presented below was made by myself and Günther Stabe before I acquired the brochure for the Funktionsmodelle model. It is provided for academic interest purposes. Numerous photos from the parts catalog and book published by Diesterweg are also provided.

On September 27th, 2013, I acquired a Lectron-MW era Grund- und Ausbausystem 1 S model. Fortunately for me, several post 1976 brochures were shipped along with it including the heretofore elusive Funktionsmodelle brochure. We now have a full description of the model and associated blocks! The complete brouchure can be seen under the Lectron-MW era documentation tab.

As detailed in the 1976 red brochure, the complete name for this model was Funktionsmodelle für biologische Nachrichtenverarbeitung. An English translation for this is "Function model for biological message processing". Perhaps the most tantalizing name for a LECTRON model ever!

From the 1976 red sales brochure:

From the February 1st, 1976 price list:

Since both the Funktionsmodelle model and the expansion model (Ausbausystem Funktionsmodelle) were not described in any detail in either the 1976 Red Brouchure or the 1976 price list and Lectron - MW era brochures post 1976 have yet to be discovered, we initially could only infer what these two models explored.
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When I put the question to Günther Stabe, he gave me his informed opinion as follows:

The development of "Ausbausystem 5" with the subtitle "Kybernetik III" has not been finished yet - it is in preparation, so people may choose the "Ausbausystem für biologische Funktionsmodelle" instead which is ready for delivery (new at that date), to expand their experiments based on "Ausbausystem 4 - Kybernetik II" and the pre-courses. That could mean, that several (or all?) experiments may be done with that set. The "Ausbausystem 4 Kybernetik II" was the set with many metal material, wire, tools and glue...

"Curriculum Kybernetik I" and "Curriculum Kybernetik II" may be extended with "Curriculum III" (still under development) or (!) "Ausbausystem Funktionsmodelle".

Another set "Funktionsmodelle - 8 110 062 (or 8 110 064 incl. power supply)" may contain all experiments of (Kybernetiks ?) including the "Ausbausystem Funktionsmodelle - 8 110 063 (or 8 110 065 incl. power supply)".

To make it short: it is still unknown, what can be done with "Funktionsmodelle" as a whole set of experiments which may cover a wider range than Kybernetik I + II + III (?). Here we are still in the area of "best guess", until more material could be found. In my opinion there were new or other guidelines for the teaching of methods in that years. I have tried to find out more, but I didn't find the "knot" 

Another problem in Germany is (until today !), that all federal states may define the school / cultural / learning goals by themselves - not global for Germany as a whole. That is not good for e.g. a Bavarian school student, to change the city (movement) and federal state to complete his school / college / ..., because the levels are different.

Perhaps the "Kybernetik" courses were replaced one day step by step by the headline "Funktionsmodelle" as a more modern kind of talking about those experimentals. Without details we are "swimming" into an unknown direction.

We don't know whether the "Ausbausystem 5 - Kybernetik III" has been ever finished successfully and has been sold and delivered, so any discussion about it will lead us wrong. If "Funktionsmodelle" was a big success they must have been discovered in newer catalogs, e.g. Lectron (RWO). This is not the case...

So our understanding to date is that the Ausbausystem 5 (Kybernetik III) was never productized but the Funktionsmodelle was released and is awaiting 'rediscovery'!
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JUNE 28th, 2013

Due to Mr. Stabe's perserverance, we have more light to shed on the Funktionsmodelle model. During a Google search, he discovered a book published in 1974 with the title "Funktionsmodelle - Versuche (experiments) zur biologischen Nachrichtenverarbeitung". Since this title was almost 100% of the full name given to the Funktionsmodelle in the Red Brouchure, Mr. Stabe ordered the book. Upon its receipt today, Mr. Stabe conducted an initial cursory examination of the book which revealed that this was the academic instruction manual to complete experiments in this topic using the LECTRON system. Mystery solved! Bravo Mr. Stabe!

The following scans were graciously provided to Lectron.Info by Mr. Stabe to provide the LECTRON community with the latest information.

The following is a full introductory description of what is accomplished in this curriculum. The LECTRON is mentioned as the tool to perform the experiments in the penultimate paragraph.

My speculation about the 'mystery' blocks on page four in the 1976 Lectron - MW blocks catalog version 1 (shown immediately below) being associated with the Funktionsmodelle was proven correct by the ensuing graphics from the book. At this time, I did not have a copy of the version 2 brochure which included a descriptive title above the blocks.

This half page from the 1976 Lectron - MW Era blocks catalog was devoted exclusively to the Funktionsmodelle specific blocks and parts (although the Flip Flop was not shown in any of the Funktionsmodelle model variants illustrated by the brochure):

My speculation turned into proof by the following graphics from the 1974 book.

Many thanks to Mr. Gerd Kopperschmidt who pointed out to me that the captions for the Schmitt-Trigger block and the Differenzverstärker block are reversed in the above graphic!

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Mr. Stabe has provided additional information from the book and offers more answers about this intriguing model.

Through painstaking research, Mr. Stabe has prepared a complete list of all the LECTRON blocks needed for the Funktionsmodelle experiments.

One can see by the blocks inventory prepared by Mr. Stabe why the Funktionsmodelle was so expensive!

Mr. Birett (the author of the book) devised an ingenious approach to helping someone visualize the individual LECTRON blocks through the use of a transparent 'foil' (rasterfolie) that could be placed on top of the experiment's schematic in the book. The book used only a few actual photos of the LECTRON so the foil was helpful in setting up the blocks correctly.

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