This is my first post. I am a total newb at model railroading. I have started with a small HO scale layout and am having difficulty with the turntable. I’m using an
Atlas Cab A Cab B Controller and two Selectors(number 1-8) along with two power supplies. The problem I am having is that the throttle on the power supply is running the turntable, when I increase the throttle the turntable motor moves faster and sounds like it is straining. Where did i foul up? Any help would be appreciated.
It doesn’t sound like you’ve done anything wrong. The Atlas turntable motor runs on a DC motor, just like a locomotive. It needs a DC voltage, which is normally provided by the “track” terminals on a power supply. Some power supplies have separate fixed DC outputs, but many don’t.
The Atlas turntable is “indexed,” which means that it automatically stops at each track slot for a while and then continues. What you may hear as “straining” might be the stopping for the indexing, or else the motion. If the turntable doesn’t move for a while, though, make sure the approach tracks and sidings aren’t binding on the turntable deck and preventing it from moving.
The turntable motor unit itself needs to be treated like a section of track. It needs a DC voltage and a reversing switch, which is a DPDT (Double-Pole, Double-Throw) switch like and Atlas “Twin.” Then, the track on the turntable also needs to be a separate section of track, with its own DPDT, because it needs to reverse independently of the main line.
On the Atlas turntable, you will notice that the track slots are labelled either A or B. The A tracks are wired “the same as” the track on the turntable, while the B tracks are wired “opposite” to the turntable.
I used a seperate power supply to run my Atlas turntable, as well my switch machines and lighting. And depending on the vintage of the turntable, it may sound wierd to begin with. Mine is the orginal design, so the gear noise is loud.
I have an Atlas turntable as well, and it sounds as if you have done everything right. They ARE noisy!! Don’t be alarmed by that. Welcome to the forum!!!
So would there be any special tricks to wiring one for DCC? I have my old Atlas TT left over from the 60’s and would like to add it to a branch line on a new layout I’m planning. Trouble is, it won’t take anything larger than a 2-6-0!
I’ve still got my Atlas TT from the 60’s, too. I replaced it, though, because it only indexes to 30-degree steps, and the roundhouse has 15-degree tracks. I still am using the motor drive, which is a rubber-band connections. It hangs up now and then, though, and one day I’ll probably have to replace that, too. I’d have to give Atlas credit for keeping things so compatable over the years.
On thing I wonder about with a DCC installation is programming the address. On my Lenz system, I have to do this on the programming track. Of course, I can’t run the turntable over to the programming track, so I guess I’d have to jumper the connections directly to the turntable. Right now, though, it’s just on a DPDT switch with independent power from a similarly-ancient pre-Beatles power pack.