Relays on Reverse Board

That will be hard, you need to pry the clear case away from the little bump in the middle of the white base on each side. It would be easy if the relays were off the board.

Thanks. Looks like it will be impossible without unsoldering one of the relays. The covers are almost touching and it doesn't look like there's enough room between to pry the cover loose, even if I could find a tool slim enough and stiff enough to push the tab outward. I think I'll put it back together and see if reversing it a couple of dozen times will loosen it up. That engine probably had not been run in 20 years when I got it. It works OK, you just have to wait for the relay to get the message.

Does the engine reverse as soon as the relay closes? If so, the delay is in the electronics, and not a problem with the relay contacts.

Larry

Don't look like any Williams circuit board I have seen in the past, also the engine appears to have only one motor.

Is that a new Williams by Bachmann reverse unit?

If so you may damage it instantly by using any spray cleaner on it. Spray cleaners are not meant for modern electronics is what I was told at my local hobby shop.

Use some compressed air around 5 to 10 psi instead.

Lee Fritz

Not that it's any help, but, boy that reversing unit takes me back to the 1980's. You

can get command, cruise and sound in a footprint like that now. And actual, physical

"relays" in an "electronic" RU. I've removed a few of these during a command upgrade, but I have no idea how to get under the cover.

What TrainLarry said, and what D500 said.

I had a Williams Hudson that had problems with the reversing unit, but I can't remember what I figured out what was wrong with it.

It had this nasty habit of going over something, maybe a lack of power, and jumping to neutral and slamming the whole train.

Actually the more i think about it, the more I think D500 is right, go for an Electric RR conversion,  you would still have conventional and get TMCC to boot, and maybe sound if you want.

Southwest Hiawatha-

Since you would have to remove the relays to service the contacts, it might be easier to outright replace them with new parts. If you have the relay part numbers (which I think are on the plastic covers), you should be able to locate the replacement part. My guess is these are common relays, (and guessing) around $10-15 each.

-John

If the two relays cost $10-15 apiece, it would be more cost effective to replace the whole reverse board with one of the QSI or K-Line ones in my junk box. For the moment, I'm just going to leave it. It works as is, it's just a little slow. 

That is a Williams from the Brass engines.  The 2 transistors probably control the relays.  I would measure the coil resistance and see if they match.   I also think I would check electronics before the relay.  The micro chips can go bad and the output voltage is too low, or the transistors are not working.  They are inexpensive and easy repair.  Getting the relays out successfully can be difficult at times.  So that would be my last resort.  G

I'm beginning to think I'm tilting at a windmill here. I just spent some time running the engine around the layout, backward and forward, and the behavior of the e-unit is consistent. You need to power off, power up in neutral, power off, then wait about two seconds before the relay clicks in and you can power up in the next mode. It's consistent between forward and reverse, and over many iterations. One, two, CLICK, go. I'm thinking that's just the way it works; it's not instant like the change of a mechanical e-unit or a more modern reverse board. It never fails to function if you wait the two seconds. I'm thinking that's perfectly OK for normal operation, it just takes some getting used to. 

There are few things you can try. First, I would do a search for the actual schematic drawing, if it exists. I'll bet someone, somewhere, has back-engineered it or drawn the diagram. Timing is accomplished by using capacitors. Those cylindrical items are capacitors. Check the tops of them, where the X is embossed in the "roof" of the cylinders. If they are perfectly flat across, they are probably OK. If the X is raised, like a very shallow pyramid, then the capacitor has gone bad. If you can trace the capacitors and see if they are connected to the relay coils, then they are the ones that control the timing. You can eliminate them from the circuit, but I hesitate to try to tell you all the steps to take, typing on this thread. If you have any friends nearby who understand electronics, such as a HAM radio operator, that would be a good choice of a person to help you to play around with the circuit.

Ok, That is good news.  Yes these boards do respond slower.  Even new boards can do that.  They are designed not to reverse on the slightest interruption of track power, lets say from dirty track or a bump.  G

Thanks G. I have a lot of respect for your expertise so I'm glad to have your confirmation that the unit is probably working OK. 

I think you could slip a small screw driver under the open (coupler) end and pry it up. If that doesn't work just drill a hole in the cover, spray in your contact cleaner, and cover the hole with tape or just leave it open. Its in a pretty clean environment.

Pete