TMCC/Legacy Track Signal Booster (Dale's Legacy Continues)

Here's another success story for Dale and John's buffer.  I run TMCC only on a very large layout with about 2400 feet of track.  I've added earth ground wires wherever needed so the layout typically runs very well.  In order to test the unit, I disconnected an earth ground above a track in a tunnel (where there are 2 overhead tracks).  A diesel with marginal antenna would run through the tunnel with headlight blinking wildly and would sometimes stop in the tunnel.

With the buffer up and running, both blue LED and green LED lit, that same diesel runs through the tunnel smoothly at any speed with an absolutely rock solid headlight.  No flicker at all.

My DC voltage measurements are 2.75 volts at the Base terminal and 3.86 volts at the Boost terminal.

Good stuff!

I'm guessing the boost is being measured connected to the layout.  Sounds like you do have a lot of track, it's actually loading down the buffer some.

Green and red?  Are you sure you're not talking about the blue power LED?

What are you using to drive it, the original TMCC command base, or a Legacy command base?  The older TMCC command base doesn't put enough signal out to get the green signal indication.  If you're using the Legacy command base, it's not putting out a full amplitude signal.

John, I am using a Cab 1l system, I attached a pictures howing both red and green illuminated.

Ray

There's probably some oddity of your base signal, that light is directly monitoring your base signal.  It doesn't affect the buffer operation, if it's working fine, I wouldn't spend too much time on it.

Looks green (mostly) in the photo...

Ok, Thanks John, as I mentioned I did run for a short time and all seemed well. Will run more and see if signal is continually good.

Ray

Photos of LED's are difficult.   Since it's a R/G LED, at different angles, it looks different.

John, you are so right as to the difficulty in photographing the LEDs, I spent a lot of time to get the pic,almost gave up.

Ray

Yes the sensors are not like eyeballs,  but handy for seeing IR.

Ray, that is a good picture, it is exactly what mine first looked like. My advice is if the layout is working, ignore it. I still have some unexplained signal issues on my 2 rail layout but fortunately found a temporary fix that by all logic should not have any effect. My current thought is one of the AS-AR-AC boards is "defective." I am not sure if you have any of these on your layout. My illogical temporary fix is to keep track power on the Turntable pit rails which are fed through one of the AS-AR-AC boards. If I do this one thing the layout works perfectly, otherwise I have signal issues even with a solid green light on the Buffer.

Ray, if you will be at S Fest we could meet up.

Tom, As far as I know, I don't have any of those boards on the layout. I ran the locomotives that had problems for a longer period today, the problem surfaced when running as a consist. The two areas that were troublesum showed no problems now. S Fest, at this time I am not sure if I can make it but will keep this in mind.

Ray

I received my legacy control base back from Lionel today. It now has a bright green light 2.001 volts to buffer and 6.37 volts to track. everything works great. The only problem is my engine roster is gone  and the base is unnamed. I can view the list on my cell phone WiFi when not linked to base is there any way to restore roster to base?

Jprails posted:

I received my legacy control base back from Lionel today. It now has a bright green light 2.001 volts to buffer and 6.37 volts to track. everything works great. The only problem is my engine roster is gone  and the base is unnamed. I can view the list on my cell phone WiFi when not linked to base is there any way to restore roster to base?

Yes, but only if you had backed it up first.  I do this via the Windows Legacy System Utility.  If you're not familiar with this, I think you may have to enter things again from scratch.

But...if you go ahead and install and use Lionel Legacy System Utility, it's easier to install the names, numbers and options for all your engines with a real keyboard.

Not only that Chuck, but you can just use the list on the WiFi to get all of the stuff in, easier to transcribe if you have the data to look at.  Of course, if you have sensor equipped locomotives, you just drive them over the sensor track.

DM TMCC Buffer kits are now available.  I've attached the kit instructions and the buffer user's manual to this post so you can evaluate your need and your ability to construct the kit.  Each kit contains all the materials you'll need to build one buffer.  Thru-hole construction was used to make the assembly easier.  Also, the cases were prepped with the holes and slots as without the drilling fixture, that would have been more time consuming.

DM TMCC Buffer Kit Documentation.pdf

DM TMCC Buffer Documentation.pdf

Contact me via my profile address if you want one of these kits.

Been having problems with the two sensor tracks on my layout. Tried resetting them checking all the plugs. Everything seems OK. The only thing I changed was adding the booster. Disconnect the booster sensor tracks work. Checked the hookup wiring on the booster and they are in the right spots. Hook the booster back up and the sensor tracks stopped working.  The booster is about 16 inches from the Legacy base. Have a powermaster bridge nearby but I tried taking that out and it didn't make any difference.

Well, I'd try moving it farther away, but 16" should be sufficient.

As an experiment, we could try cutting down the boost, here's a simple voltage divider to reduce the amplitude of the signal while still keeping the low impedance drive.  See if this changes the situation.

I cut the trace between R5 and C6, easy to do, and soldered a couple #24 wires to the edge of the chips. And then the other ends to a 1K potentiometer. I was looking in the junk for a 2K but the 1K, 1/8 inch mounting,  is adequate for a variable gain and takes up minimal space. Instead of 3.3 gain, it now varies from 3.3 down to 1.65 which is where I leave it. Modest layout, but I like having the booster and seeing the green LED since I am familiar with the broken Legacy base with the greatly reduced output.

Be cautious tack soldering the pre-tinned wires on to the edges of the chips, because too much heat will cause the chips to slide off their pads.

I moved the booster about 10' away and no change. Don't have any resistors but I have some diodes.  The number on them is RL207. Under that it says mic. Would those be OK to try. Don't really know much about his stuff.