3. Block Board Order Campain

As announced in Hp1 3/2004.

Translation note: Not all terms could be translated. Those terms are marked with a (D) for "Deutsch".

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As the second order campain for block boards became quite popular with 70 kits, there is now a third campain. But this time with less time pressure. Deadline for an order is the 20th. February 2005, i.e. the weekend with the FREMO meeting at Bad Oeynhausen. The kits are expected to be deliverd at the official anual meeting 2005 at Hochdorf-Assenheim and at the "main line" Ascention Day meeting at Pritzwalk. Those who are unable to attend either meeting will get the kits via a member to be named.

Those interested in the absolute block system should read the artikel of René Pabst in Hp1 2/2001. Currently this artical is only available in German. Even with the article being dedicated to the Tf-71 block it describes the general operation common to all types of absolute block systems. The connection to the station is always the same. There is an English description of the manual block (known in Germany as "Felderblock") from Joern Pachl. More information about the electronic absolute block system within FREMO is availabe at the FREMO Block Homepage

Prerequisites for the Block

Basically there are two prerequisites for the implementation of the absolute block system:

  • The station has entrance and exit signals
  • The station has station interfaces in relay technique

The station interface in relay technique is kept as easy as possible and is (nearly) exactly the interface described in Hp1 2/2001. Only a connection between formerly unused pins for the permission passing lock has been added.

It shouldn't be hidden that for stations, where multiple lines (or multiple tracks in case of bi-directional line operation) may be reached from a single internal track an interlocking of routes is required, as the exit signals need to be locked depending of the exit direction. Of cause this increases the expense, but provides more safety in operation.

For large stations the block technique is still attractive, as it provides the base for automatic train number forwarding.

How many block boards do I need?

This depends clearly on the type of line and what is planned to be build. Generally the number of block boards equals the number of station interfaces. But you should ask yourself, whether block boards are needed. Essential for participating in the absolute block system is the station interface. If the neighbouring station is equipped with the block, a free block box may be used. Currently there are at least five available. But who wants to integrate the block into the control panel or has an interest in the automatic block system should not be kept off from ordering block bords and building block boxes.

Single Track Route

Each end of the station needs one block board. To cover both ends of a route this results in two block boxes. Same for a through station with integrated block boards. Of cause a dead end station needs only one board, a diverging station 3 or more boards depending of the number of lines connected.

Double Track Route with Uni-Directional Tracks

As long as the double track route is solely operated uni-directional there are no more boards needed as for a single track route.

On those routes at the prototype the wrong line operation is known, but this bypasses the automatic block system and is used only in case of faults. Additionally there is the signalled wrong line operation which is based on interlocked routes within the station and a signal at the "wrong" track at place of the entrance signal on the regular track. But stil the security of the block is bypassed and the reporting back has to be re-established.

Double Track Route with Bi-Directional Line Operation

A double track route equipped for bi-directional line operation represents for the absolute block system two independent routes. Therfore twice the number of block boards is required.

Delivery Items and Options

The items delivered with the kits are the printed circuit board with all components to be mounted on it, a 1.8 m long 15 line cable for the station interface (optional), one (optional 2)5 m long 9 line cable for the block interface, parts for the cross over connector, one connector and 0.5 m flat ribbon cable to connect the user interface and the connectors for the LOTUSnet and logging interface. The Excel file contains a detailed listing. It allows for three options:

The board provides pads for three types of connection. SUB-D connectors straigth, SUB-D connectors angled and double row pin header for flat ribbon cable IDC connectors. The last option allows connectors remote from the board, but needs in any case further parts. Therefore this option is not offered. This narrows the selection to the straight and angled SUB-D connectors. Depending on the mounting of the board within the box or control panel one or the other version may be better. With the straight connectors they reach through a plain parallel to the board, with the angled version they lock in the direction of the long board edge. In both cases the the connectors are mounted on the bottom side.

With the previous order campain each board came with one cable for the station interface. Is the board integrated into the control panel and the station interface is realized as pig-tail, the cable is not needed. Therefore this cable is optional. I will reduce the price by 1,15 Euro (based on the current price at Reichelt).

With the block cables we found out that two times 5 m is not sufficient in most cases. Meanwhile there is a pleasent amount of track modules. Therefore I offer to order two block cables per board. The addional cable costs 2.30 Eoro.

On the page about the block board there are further options noted, but they are (as noted on that page) not considered due to lack of potential savings.

Obviously the base price for the kit is dependent on the number of boards and the parts cost in February 2005. But I expect the price to be about 40 Euro again.

Order Informations

With the previous order campain I needed to ask multiple times, what the customer regarded as one "set". Some thought about one kit, others a board pair for a single track trough station. Please note always the number of boards. Of cause all other parts in the corresponding number will be delivered with it.

With the previous order campain there was one cable of each type per board. As stated above this is handled more flexible now. But please state always the total amount. Not the number per board.

Also as a result of the previous order campain we (the devellopers) think that it doesn't make a lot of sense to put the Atmel controller into the kt, as many send these parts directly to someone able to program the Atmels. Therefore it is better to tell who will programm the parts and let me forward them to these directly or that one of the customer does this for other customers. Currently the following persons can program Atmels:

  • Stefan Bormann
  • Moritz Hebert
  • Dirk Jahnke
  • Bernd Wisotzki

For the software devellopers it is essential to know, which type of prototype absolute block system is to be modelled. Therefore each customer should contact the developers (those are the same as the persons above). At latest at time of ordering the prototype block type should be known. But this is not a requirement for the order.

Currently software already exist for:

  • Single track relay block as "DrS" version (Siemens (D)Stelltische)
  • Tf-71 block (there is only a single track version!)

In development or planing stage there is software for:

  • Double track automatic block
  • Double track relay block as "DrS" version (Siemens (D)Stelltische)
  • Single track relay block as "WSSB" version (GS II DR (D)Stelltische)
  • Single track manual block "Felderblock Form C"
  • Single track relay block with button oeration as with E43 signal boxes


The order shall contain the following:

  1. Number of boards
  2. Straight or angled connectors
  3. Number of cables for the station interface
  4. Number of block cables
  5. Who will programm the Atmel devices
  6. Which prototype block type will be modelled
  7. At which meeting the parts will be received or who else will get them where

One addional request: It is more practical to populate the boards not in a "single fighter fassion" but within a group. The parts for such a group may then be packed into one box, making my sorting work much easier. Therefore I ask everybody to decide before the order deadline at the 20th. February 2005 with whom you will work together.

Orders to Reinhard Müller

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