OTT Machine Bascule Bridge Sound Board

Mine has been in place for years and I would have to see if the instructions are still around. 

Mine is wired with a momentary start switch for activation.  Your circuit obviously doesn't have a switch in the circuit.   Double check for crossed wires, etc.

Susan, Hi. 

Last time we talked it was about my MI-Jack crane a while ago. 

I think the instructions for Ott are not quite correct. I got things working by having both devices in line with the same momentary switch. Only problem with this is both start at the same time and tge bridge is up up by the time the warning siren finishes. Did you overcome this?

Here are the Ott instructions that I found.  My momentary switch is connected to the bridge per the bridge wiring diagram in the instructions.  The Ott circuit board controls the timing of the sound in relation to the motor once the Up or Down sequence starts.

Thanks Susan.

In your arrangement, do the bridge and sound board kick off at the same time?  I want the bridge to delay until the warning siren stops and I don’t think that is possible this way, unless I am totally misinterpreting what motor drive terminals 1 and 2 are. Did you have to open up the bridge to wire this up?

Forrest Jerome posted:

In your arrangement, do the bridge and sound board kick off at the same time?  I want the bridge to delay until the warning siren stops and I don’t think that is possible this way, unless I am totally misinterpreting what motor drive terminals 1 and 2 are. Did you have to open up the bridge to wire this up?

Yes, the bridge motor and siren start at the same time.  The bridge sounds continue a while after the motor stops.   When I remove the roof from the bridge building it appears I tied wiring into the circuit board.  (I don't remember the details.)

If you're comfortable with wiring modules, perhaps a so-called "Delay On" relay module might apply.  You apply power to the relay module, it waits an adjustable time (say, 10 seconds) then closes its relay.

I'm not familiar with the Ott sound module nor the bridge motor requirements, but the idea would be something like this.  You apply power to the "Delay On' module simultaneously with the start of the siren sound.  You set the delay time to the length of siren sound.  The module delays the application of voltage to the motor terminals so the start of the motor movement coincides with the start of the motor sound.

There's some homework to do but I'm thinking less than $5 out-of-pocket.

I had thought of something like that, but it is totally beyond my skill set and current physical capabilities. My fall back position is separate switches to manually kick off at different times. 

Despite the wording of the instructions, I don’t think the Ott board is controlled by the drive motor at all; it uses the same momentary trigger that the bridge does. 

Thanks Susan and Stan2004. 

Come on Forrest, live a little.  What Stan's suggesting is pretty simple.  All you're doing is powering the sound module and the timer board at the same time, the relay on the timer board is controlling the power to the bridge.  So, when you start the sound the timer module starts it's time delay, when the time delay expires, the relay closes and the bridge starts moving.

And if I try it and fry the board and/or the bridge???   

10 years ago I could probably have figured it out. I do have a background in programming. Now, however, I have chemo brain which led me to hook it up wrong once already. 

Well, with just a tiny bit of guidance, I can't see this unit cooking your board.

For example, both of the devices in question are AC. Both are powered by 14v. The bridge supplies a 3v AC circuit that acts as the trigger to the circuit board in the bridge. The circuit can be activated by an insulated rail, a 153 pressure contact, or a push button momentary switch. I use the latter. The sound board needs the same 3v momentary trigger. 

The relay Stan suggests is DC. That throws me right there. I also can’t figure out if it will send a momentary burst or a steady current. I have had devices from China before and I would not expect much from the documentation. 

Someone must have solved this long before I encountered it. Head hurts. 

This feature should have been built into the sound board. 

Forrest Jerome posted:

I had thought of something like that, but it is totally beyond my skill set and current physical capabilities. My fall back position is separate switches to manually kick off at different times. 

Well, it appears you have a solution that is in your comfort zone.  I appreciate the apprehension about mucking around with "momentary" triggers, AC vs. DC, etc.

If at some point in the future you find the time and motivation to upgrade your bridge animation, pose this as a project in the Electrical Forum.  I notice Susan's instructions are dated 1998.  A lot has happened in electronics since then!  For one, I'd think the sound quality of $1 MP3 sound modules would be night and day compared to 1998 technology.  The "problem" is O gauge accessories are not a high volume consumer market with productions only in the hundreds or maybe a few thousand units.  The point being it should be expected that some DIY tinkering and muddling is required to make your layout do what YOU want.  The availability of insanely low-cost electronics modules on eBay has, in my opinion, been a game-changer for the O-gauge operator.  Combined with forums like OGR to exchange ideas... let the good times roll!

Actually, it sounds great. 

I will take note of the electrical forum. 

Which Bascule Bridge do you have? The metal pre or post war or the newer reproduction?

It appears that you have the trigger wires connected to constant power.

I would suggest attaching the trigger wires directly to motor leads. Either version of the bridge cuts power to motor at the top or bottom of the movement and would then break the trigger circuit.

Add a lead to each motor wire internally and drop those to connect to board (blue ) leads.

Do the wire colors on the sound board that you have match those in the instructions that Susan posted?

Yes the wire colors match. Bridge is from 97, I think. 

What you suggest would not deal with problem of both devices starting at the same time. By the time the warning siren finishes, the bridge would be up. 

A delay circuit is the answer. I just have to figure it out.