The Costerfield Line - Rebuilding the Great Caravan Railway
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Send and Receive I have done some basic thinking. At the moment Mark has a system basically similar to this circuit shown here. It is a form of send/receive that at a basic level mimics the sort of double line block or ABS. It allows each staion to send or receive, and if the switched line up, you get a greeen to enter a block in a certain direction.

But while it sets direction and provides safeworkingbetween stations, there is still no protection at the stations. So I have added a home and a starter signal into the mix. The Home signal protects the station you approach. The starter signal gives a train permission to leave a station.

But there is no control of the home signal.
But then I tried this diagram (below) to control the home signal. This will allow a station to set the home to red regardless of the send/receive system. The idea is to allow a train to come but stop at the home. When sending the home is irrevelant. However I have not thought a lot of the Starter signal, which shouls only come off if the send/receive is correct.
So this is what I would want, if using the send/receive system. Each end os a single line secion has two switched. The home signal will go to red,if the staion operator puts it back, or if the direction is opposite. The starter signal will come off only if the diections match and the signal is pulled off.

this would be some complicated electrically, and I haven't tried to do it yet.

More thoughts on the to/from systrem, and by jeeves I've got it ! This circuit will work. It is a combination of Mark's system and a set of signals at each end of a station/loop. One can make a bypass for Hazeldale loop if required as well, as that is just a set of relays.

Thte home works manually, it will be green only when selected. The Starter will only come off only when the send/recieve is showing send correctly. If the sent/receive is not right, the starter cannot go green.

I have displayed a few panel examples. The staging panels do not have a home/starter signal - they do not need it ! I have also shown a block occupied indicator - whch is totally optional. The indicator will show there is a train in section though.

The power can be the same for each panel, and it means there is effectively 2 wires between panels - providing the power is the same source anyhow. 12VDC is easily ok here, the main item is the relays. LED's and resistors also just need working out.

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