I use the last generation of Walther’s turntable although I suspect the brand new ones must have the same ring gap. The problem is that the BLI Paragon 2 & 3 locomotives on the turntable as it rotates and crosses the ring gap, the loco’s stop producing sound and must have a speed input to get them back to life. This requires some careful manipulation to keep the loco on the bridge and fouls the whole sound effect.
I’m wondering if capacitors can be added to the turntable to eliminate this problem? I think this could work as the “gap time” is very short. I have no idea where one would attach the keep alive capacitors. Walthers answered this question with a single statement about voiding the warranty. I would really appreciate some advice on this- other model railroaders must experience the same problem. Thanks in advance.
Not easily. The power is brought up only through the center bolster of the turn table. This would require dissassbly of the bridge (waranty voiding). You would have to disconnect the wires from the track and route them to the capacitors. The reason for the gap is so you dont dead short at the exit of the turntable (also why there is a no track area on the drawing). It is a manual reversing circuit.
I suspect that if you were to keep the tracks live with a capacitor, you would end up with a momentary short circuit when the power reconnects. This will have the same result as before, execpt your command station shuts down.
I dont know if you can install keep alives in BLI decoders.
You can add keep alive capacitors to any decoder, it’s just a matter of finding the right place to connect. Since the BLI decoders are somewhat more proprietary than others, this may not be quite so easy, but the basic circuit at a high level has to be similar to other decoders as far as having the bridge rectifier as the first thing in from the track pickups. There are likely existing capacitors designed to keep the sound system going, but the probably aren’t big enough to clear the turntable gap. For a case like this, you don’t really need a huge keep alive that also powers the motor, so it MAY be possible to increase the existing capacitors just to keep the sound on.
Can you bypass the split-rings somehow and just run the turntable bridge through and auto-reverser? That should give you a faster polarity flip, and the flip will occur when you enter or leave the bridge so the engine will be in motion as it happens.
Thanks for the comment. Indeed there are existing capacitors. Attaching an additional capacitor is, according to BLI, a warranty breaker nor will they offer any real comments on this dilemma. The 2 year warranty is something I am loathe to violate.
Thanks for the comment. What an excellent idea. Makes one wonder why Walther’s spec’s or the turntable manufacturer/designer didn’t incorporate this. Probably because of additional cost. I need to figure out, if possible, how to eliminate the gap. I think I have had the turntable a long enough time where warranty is no longer a consideration.
I use NCE DCC and since the turntable stopping points (tracks) are enabled to be controlled digitally thru the command controller, I’m wondering if the track selection couldn’t be run thru a device like the NCE Mini Panel creating a macro to switch an auto-reverser to the outgoing track. I’d sure like to see your and other’s comments on this.
Im not sure if the ring arrangement of the power pick up will allow that. A similar arrangement would have to be engineered to allow power to go to the rails (you cant just run a wire, because it will become twisted up). I could take a look at mine at some point over the weekend to see if it is feasible.
It requires a little work because there are multiple contact rings on the turntable shaft (all the electronics and the motor are in the bridge) but I’m pretty sure I’ve seen someone post that they’ve done it.
There are 3 rings on the bottom of the Walthers 90’ TT. The outside split ring is track power. It works by the fingers in the pit contacting the opposite sides of the ring. The gap is the auto reverser. There are 2 other rings and a center disk that all have fingers contacting them all the time. Im not sure what these 3 items do, but if I had to guess, 2 are the motor and 1 is the auto indexing system?
The following statement is a WAG and I dont actually know if this will work, use at your own risk:
Remove all electronics from the TT. Install the best motor decoder you can find (or maybe a sound one with air pump noises or electric motor sounds). Hard wire the track power for the table into the table motor supply wires. Use the same wires to provide power to the decoder then connect to the turntable motor. Install a DCC Auto Reverser in line with the turntable’s new power.
Remove all locomotives from layout. Program turntable on main. Use your throttle to spin turntable (slow speed motor control very important).
This uses only 2 of the rings on the bottom. You might be able to put some conductive paint across the other ring and use it for something else (lighting on the TT bridge or something).
The above is an untested theory. I have not tried it to see if it is practical. I provide no garuntee that this will actually work… And it definitely voids the warranty.
If my memory serves me well,our friend Digital Griffin has initiated a post on this specific issue.It was then a nice exchange of knowledge that had brought an interesting solution to this problem.
I believe this post was about a year ago.If it can be found,it’s a highly interesting read.
I think there may be a bit of confusion in the linked thread about which Walthers 90’ turntable is being referred to. If I understand correctly, the factory assembled turntable is wired differently from the kit turntable. The factory assembled turntable apparently is the one with the split ring to which most of the posters in the thread are referring. I know from recent experience that the kit turntable does not have any split rings. One poster in the linked thread, Split Reduction, is apparently referring to the kit and is not aware of the differences between the two. With the kit, an auto reverser should be easy to hook up. Just use it to feed the bridge track. Am I correct or am I missing something?
I recognize that doesn’t help the OP with his problem but I thought I should mention it so those of us with the kits don’t get confused.
I followed the link and thank you for posting it. It is quite interesting but Mel’s solution is beyond where I want to go. What an excellent job he did.
If you are refering to the Walther’s turntables, I didn’t realize they made a kit TT.
Thank you for the input Randy. BTW, I did repower my Roundhouse ALGEIR w/ a NWSL truck drive. Took some milling of the frame and I changed it to an end door body. Attaching the original truck sideframes is problematic but I’m working on it.
The kits are the pits! Pun intended! They require a lot of TLC to get them to work properly. I built one not too long ago with some modifications to get it to perform decently. Here is the condensed thread:
Note that the design of the kit turntable is different from the pre-assembled one so the above information won’t do you a lot of good unless you rip your existing turntable to pieces or swap it for a kit version.
I’ve finally installed and used mine (N scale) and to me it’s a jewel.Since it was designed so that it could be used for either DC or DCC,it has to control the track polarities mechanically,thus the two half circle slips (one for each track) and the gaps between,wich are the issue here.There’s a dead spot every half rotation that can’t be avoided.
I’m having the same issue and the only solution I can see is finding a small two paths slip ring that I could install on top of the middle arch structure.The slip ring assembly could then be held steady with a small tube (carrying the DCC) tied to an outer structure,like a shed that could also hide a reverser.However,finding a slip ring so small can be a problem.
May be doing this from under the TT is possible,but won’t try it.The N scale version is so small,I fear I might just ruin it.