I picked up a few of the MTH 7-light block signals at York over the weekend. Rather than using the internal timer circuitry, I would like to wire them up so that each vertical, diagonal and horizontal state are individually, without the timer functionality. Is this possible? I want it to work more like a basic red, yellow green block signal.
Let me know,
Glenn
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Funny you should ask. I have some of these that have toasted their internal board that I was mapping out so we could use them with our own wiring.
GRJ, If you have some time, how's about we completely map out the signal for the record? From a previous thread, fec fan provided us with the schematic of the timer circuit as below. Does the 7-block use the same circuit board ... but perhaps with an additional loose resistor to power the center LED? I see in your wire colors that Purple is both + and - which suggests the same bipolar output of the 555 on pin 3 to drive yellow and green. So this would affect how Glenn needs to insert diodes if directly wiring to the LEDs.
If you haven't already sketched out the schematic, are the pairs of LEDs hooked in parallel or series?
Since the boards were physically smoked, they're no longer in the signals and I tossed them. They actually went up in smoke. All I have is the wires coming from the signal head to the base. I don't currently have a complete signal with a working board.
Did you determine if each pair of LEDs in the outer ring are in series or parallel?
Truthfully, no. I just used a 1K resistor with a P/S to find out what would light them, I haven't gotten back to the project again as I have other fat in the fire lately.
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