Signal Sounds Board Pinouts

John

  I am not sure about this, but you can try.

Pins 1 & 2  Hot

      3 & 4 common

      10     Serial in

      22 & 24 speaker

Maybe Jon Z will chime in.

 Bill

Thanks bill.  I'd sorta' like to be sure, I only have one of these, and cooking it is probably not advised.   I'm pretty sure you're right about the power, I just wondered if this was looking for DC power from outside the chip.  All I see is a TO-92 package for +5VDC, doesn't seem enough to drive the audio.  I see a Darlington connected to the heatsink, could that be part of a power supply for the audio?

I see connections on the board to 20, 18, 16, and 14 on the back side of the board.  1,2 are also connected and look like power, I'm assuming 3,4 could be the internal ground plane.

I know there's a DC volume control on these according to the audio amplifier chip spec, so probably some leads are accounted for there.  Looks like 16, 18,and 20 are the volume pot.

Since this board plugs into the same socket as the RailSounds audio board, I guess I could assume that connections would be similar...

Too bad there aren't schematics for these, it would make figuring this out a lot easier.

They all have schematics, they are printed on the underside of the PCB....just need your magnifying glass and DVM!   On a serious note, they are a direct plug in to the RS spot.  Some motherboards had jumpers to switch, but power, data and speaker where all the same.  G

I never considered using my microscope, thanks!

I thought that they had the same pinout since I did an upgrade a long time ago and just plugged in the two RS boards in place of the SS board.

I think I'll connect it up and see what happens.

I have found on sunny days I can hold the boards up and you get a pretty good view of the hidden PCB layers.

I draw them out on a sheet of paper and file them as I troubleshoot a problem board.

Actually been working on the QSI bottom board recently.  G

I'll be interested when you get pinouts for the QSI board.   I'm assuming you're talking about the MTH PS1 boards?

There are some similar board wiring diagrams in Lionel Product Supplements #40 and up on their site. Maybe they will give some clues.

None of the diagrams in the Lionel stuff shows the connector pinouts for the board, they just show the wiring to the motherboard that it plugs into.

Of course, now that I mention it, I could trace out one of the motherboards I have!

John!!!  I was going to mention that, but with your experience I thought better! :-)

I also do those MB pin check basically connecting the Lionel wire diagram to the board Jumpers and Jumper to pins.  Testing each row of pins to see what is interconnected via the Motherboard.  Most of it has been the early 2000 to 2004 stuff.

The QSI bottom and MTH QSI are similiar, I have actually be doing an early QSI DCRU.  Amazing how all those 2.5amp didodes are interconnected, and feed from the Bridge.  G

I've only had a few PS/1 locomotives in my hands. and all except two now run TMCC or were turned over if I deemed them not suitable for my needs.  However, since I'm pretty committed to TMCC/Legacy, I spend my time learning more about those boards.