Lock engine in forward direction

[algalli]

Hi
We have 10 Williams engines we will be using on a museum layout and need to lock the engines in forward direction.
1) I have the diagram for locking the engine in forward.  I am unable to remove the board since the holding screw does not back out.  My board looks like the revision board but I do not see a marking that  tells me it is a revision 4.  Where do I find that?

2)  If I do not want to use the optional switch shown in the diagram which two wires do I connect?

3)  If I want to do away with the board I assume I need to get a full wave rectifier and connect both sets of black and red wires to on set of rectifier terminals and both sets of yellow and blue wires to the other set of rectifier terminals.  Correct?

[phillyreading]

You probally know that to modify the circuit board you lose factory warrenty if there is any left, I want you to know this before I tell you anything else.

If you want to go the bridge rectifier route, for me the easiest and least expensive, you will need to disconnect and remove the current circuit boards, but be careful to identify the motor wires from the board, one yellow and one blue unless newer engines have different color wires. Do not remove the True Blast 2 boards as these will still work with an A.C. voltage transformer.
On the rectifier connect both track wires to one of the terminals marked ~ (there are two terminals marked ~), connect the motor wires to the terminals marked + or -
You will need a 6 amp 50 volt bridge rectifier, Radio Shack has them for around $7.50 each. Solder the wires in place for best results.

You could run your engines on D.C. however I think that you will have to remove the horn wires from the circuit boards. With the current set-up by Williams the horn will go off constantly when run on D.C. So you would have to change the horn units out to have them with D.C. voltage.

Lee F.

[phillyreading]

Just a few words about circuit boards by Williams, there have been at least five differant boards that could have been used, maybe more than five now, and you need to know which one you have before proceding further. Even a circuit board by QSI in the Crown Edition Williams engines.

That is why I chose to remove and replace my circuit boards with, 6amp 50 volt, bridge rectifiers.

My circuit board didn't act the way I wanted it to act. It is difficult to lock a Williams circuit board into the direction that you want it to go, so that is why I did the bridge rectifier procedure. Also you don't have to worry about going thru F N R to get the direction you want.

Lee F.

[Joe Satnik]

Dear All,

The Williams diesel that I own passes the track power through the reverser board to the TBII sound board,

so you have 2 options if you want to maintain sound:

1.) Unplug only the motor connectors from the reverser board.

(Leave track power and sound board plugged in to reverser board.)

Splice into 2 track power wires to feed the bridge (~) terminals.  Note that the #53 lamps are fed track power, with the return being connected through the chassis.

2.) Remove (or just disconnect) the reverser board, then connect both the sound board power-in wires and the bridge (~) terminals to track power.

(End of 2 options.)

Your connections from the bridge (+) and (-) to the motor wires should be temporary until you figure out which polarity (yellow to +, blue to -) or (blue to +, yellow to -) gives you forward direction.

Something I found interesting:  Since the front truck and back truck run in opposite directions, (one towards its coupler, the other away from its coupler), one truck motor's "dotted" terminal gets a blue wire, the other gets a yellow.  i.e., they are wired opposite polarity from each other.    

Hope this helps.  

Sincerely,

Joe Satnik  

Edit: Added "...wired opposite polarity..." sentence.   

[Joe Satnik]

Dear All,

I tested the motor wiring of my (ca. 2004) Pre-Bachmann TBII Williams GP-38 and found that

in general,

Black = outside rails

Red = center rail

Motor Yellow (+)
and
Motor Blue (-)  moves loco in forward direction.


Motor Yellow (-)
and
Motor Blue (+) moves loco in reverse direction. 

Note that the speaker wires are yellow, too, so don't get them mixed up with the motor yellow wires. 

Hope this helps. 

Sincerely,

Joe Satnik

[algalli]

Thanks for the info guys.

I successfully modified one board but the soldering was not easy.  I seemed to have several versions of the reversing board.  On one engine it worked for two cycles and them stopped.  On the second engine I must have shorted out at the resistors because I created a realistic smoking diesel.  I ended up going with  the rectifier and it was easy.  My only problem is that between the two local Radio Shacks I could only get two rectifiers.  They were 400v, 8 amps and only $2.99 each/

Al

[Joe Satnik]

Dear Al,

You could search on e-bay for "bridge 8a" or as low as 6a, as that is the amperage the reverser boards are rated at. 

Here is a 6 Amp lot of 10 example:

http://www.ebay.com/itm/Diode-Bridge-TB68-26-B-New-800V-6A-Lot-of-10-parts-/220574909655?pt=LH_DefaultDomain_0&hash=item335b4a04d7

Hope this Helps.

Sincerely,

Joe Satnik

[Joe Satnik]

Dear All,

Thought of something on this mod.

To keep track power pick ups from both trucks, you would need to connect all four wires from both motor connectors (8 wires total) to the diode bridge.

If you wanted to keep the TBII sound, you would attach the sound board's black and red wire to the same colored wires on the new diode bridge (~) terminals. 

So, on the new diode bridge:

One (~) input:

From center rail front pickup (red wire of 4 pin connector)
From center rail rear pickup (red wire of 4 pin connector)
To sound board track power input (red wire of 2 pin connector)

Other (~) input:

From outer rails front pickup (black wire of 4 pin connector)
From outer rails rear pickup (black wire of 4 pin connector)
To sound board track power input (black wire of 2 pin connector)

(+) output:

To front motor (yellow wire of 4 pin connector)
To rear motor (yellow wire of 4 pin connector)

(-) output:

To front motor (blue wire of 4 pin connector)
To rear motor (blue wire of 4 pin connector)

Hope this helps.

Sincerely,

Joe Satnik