I have two TAS SAW 1.5 boards here. One from a Sunset Rails Y6B that does not work and has wire wrap wires in it and One from a Weaver VO 1000. Both have full sounds but you can visually see but no motion at all. The one from the Weaver has visible bad transistors in it. Does anyone have any idea what transistors were used on these or where the wire wrap terminates?
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I have a SAW 1.5 board in my parts box, but it doesn't have extra wires. Without seeing the "wire wrap wires" and where they connect, I don't think anyone can answer that question.
The "transistors" under it on the heatsink are actually triacs. Just read the numbers off one of them and do a search, as I recall, they're common parts. Since you have to take the board apart to get to the triacs, I'm not inclined to check the part numbers. 
Thanks John. I meant the surface mount transistors on the top side of the board. The triacs I haven’t gotten to yet as the aluminum heat sink is no fun to take apart.
Triacs are Teccor Q4008L4. Now Littlefuse.
Not sure about the SMT transistor. Need a picture.
Lou N
There are no SMT transistors on a SAW 1.5 board, at least not on the one I have here. What are you calling a transistor?
On the right I see the four opto-couplers for the motor drive circuit, that circuit mimics the Lionel DCDS circuit pretty closely.
On the left I see a PIC processor and a couple more NEC 2501 opto-couplers. Other than that, I see a handful of resistors and a couple capacitors.
Of course, there's the big bridge rectifier, can't miss that one. 
I see yours is different from mine. I wonder if TAS sold different boards to manufacturers than consumers. None of mine have any silk screened words identifying the board. When I get back I’ll take a picture of it and send it to you.
There were a number of different layouts for the boards, I have a larger board that's also a SAW board without cruise, it's longer and a completely different layout.
Hey GRJ
I just looked in my parts bin and found a SAW Gen2 board. Had it installed in a PW engine at one time. Couldn't sell any PW engines with TMCC so I removed the electronics and then sold the engines. I have just 3 left. A 2360 GG1 that I'm going to try and sell with the TMCC. And a 2321 FM with Railsounds and an RS3 no sound. These last two I may keep for awhile as they represent two local roads- Lackawanna and Susquehanna. I've seen the actual RS3 pass thru town lately. Anyway I've been getting into G gauge with DCC. So I have some TMCC boards of various flavors. If interested I can do an inventory.
Gary
If you had some ERR Cruise Commander Lite boards, I'd be all ears. 
I don't really need TAS boards, I still have a couple in my parts box.
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