I've been running my TMCC engines successfully for several years with NO obvious connection of its 'binding post U(TRACK) to the outside rail !! This post has no connected wire....Can someone explain this, please? I.e.; WHY does it work?
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It’s RF, 455 KHz. It can propagate out of the base and be absorbed by the track. I have run engines on a piece of track totally separate on a work bench. No connection except maybe some transmission thru the air or the house wiring.
@phil gresho posted:I've been running my TMCC engines successfully for several years with NO obvious connection of its 'binding post U(TRACK) to the outside rail !! This post has no connected wire....Can someone explain this, please? I.e.; WHY does it work?
It'll work a lot better if wired correctly I suspect.
@phil gresho posted:I've been running my TMCC engines successfully for several years with NO obvious connection of its 'binding post U(TRACK) to the outside rail !! This post has no connected wire....Can someone explain this, please? I.e.; WHY does it work?
Phil,
As @cjack mentioned TMCC/Legacy gets carried to the locomotive via a radio signal (RF). It comes from a small transmitter inside the command base.
Transmitters almost always prefer to be connected to good antennas. In this case the relevant antenna system has two components:
1.) An electrical connection from the binding post on the command base to at least one of the outside rails around the layout
and, simultaneously
2.) An electrical connection to earth ground, via the ground pin on the base's power supply (wall wort) when plugged into a properly grounded wall outlet.
Why does it still work when you have only one of these at most?
The binding post is still a component of the antenna system, although not a very good antenna by itself.
Also, you undoubtedly have a small layout, the command base is located in close proximity to every foot of track, and your command base is not being picky about the poor quality of the antenna that's presently connected to it (or not connected as the case may be).
Mike
CJACK: Yes; I do the same. [But your explanation is not correct....See below.]
GRJ: I suspect your suspicion! I see no difference.
MIKE: Actually, I have a rather large layout....on 3 levels; in a 25 X 40 bldg.
ALL: The theory, a la` the prematurely-deceased Dale Manquen, which has been, with some difficulty, accepted by Lionel, is as follows: 1 leg of the communications loop is the signal radiated from the Cab-1 remote to the Command Base, which sends it, via conduction, to the house ground wires. The other leg is the house wiring itself, which radiates the signal to the TMCC engine's antenna.
At this point in time, I believe that the base-to-outside rail is not necessary. [I also suspect that Lionel will not agree. They will be wrong; again.]
Phil,
I think you have it a bit mixed up.
The signal from the Cab 1 remote to the base is not the same frequency as the signal from the base to the house ground wire and the outside rails of the track. I think the Cab 1 remote signal to it's base is on the CB band, but it's been a while since I remembered that. BTW, the signal from the Legacy CAB 2 is something up in the GHz range. Thus there is no external antenna on the Legacy remote.
Again, the signal from the base to the outside rails is 455 KHz (as is the other side of the signal to the house ground wire) and seems to propagate to the outside rails without a wire but a wire as GRJ says, is best. 
Also if both sides of the 455 KHz were sent to the house wiring, the capacitance between the ground and power wires would totally short out the signal.
@phil gresho posted:At this point in time, I believe that the base-to-outside rail is not necessary. [I also suspect that Lionel will not agree. They will be wrong; again.]
Since countless people have posted about a problem with that connection killing the Legacy signal, it's not only Lionel and Dale that will disagree, but a cast of thousands. I will also opine that they as well as I, are not wrong and that connection is necessary. 
I personally went and pulled the plug out of the Legacy command base track connection and it killed all the TMCC/Legacy operation on the layout. I have seen the same effect dozens of times on other folks layouts. I have no idea how you're wired or what you're doing, but clearly you're either lucky, or simply not reporting exactly what is connected where. However, it is somewhat pompous of you to make this declaration as a universal truth in the face of so much evidence that it is not correct.
In case I wasn't clear enough, you're dead wrong.
@cjack posted:The signal from the Cab 1 remote to the base is not the same frequency as the signal from the base to the house ground wire and the outside rails of the track. I think the Cab 1 remote signal to it's base is on the CB band, but it's been a while since I remembered that.
The track signal for Legacy or TMCC is centered around 455khz, it's an FM signal. The CAB1 communicates to the base on the 27mhz band, the CAB1L and CAB2 communicate to the BASE1L and/or Legacy base on the 2.4ghz frequency band.
How about some photos of your command setup and maybe video of its trouble free operation?
It was only a couple of weeks ago another member thought their base 1L was functioning without a wall wart....until they looked under the layout to see one plugged in.
@phil gresho posted:CJACK: Yes; I do the same. [But your explanation is not correct....See below.]
GRJ: I suspect your suspicion! I see no difference.
MIKE: Actually, I have a rather large layout....on 3 levels; in a 25 X 40 bldg.
ALL: The theory, a la` the prematurely-deceased Dale Manquen, which has been, with some difficulty, accepted by Lionel, is as follows: 1 leg of the communications loop is the signal radiated from the Cab-1 remote to the Command Base, which sends it, via conduction, to the house ground wires. The other leg is the house wiring itself, which radiates the signal to the TMCC engine's antenna.
At this point in time, I believe that the base-to-outside rail is not necessary. [I also suspect that Lionel will not agree. They will be wrong; again.]
Phil,
Your theory has several problems. First, since house wiring (hot) and house ground (neutral) run along side each other a mere 3/8" apart throughout most of the house (within the non-metallic sheathed cable that carries them, i.e. Romex) they could not broadcast the RF signal very effectively if your theory were correct. They would need to be spread apart, which is what happens when the outside rail is used instead for one half of the antenna.
Second, Dale (may he rest in peace) is no longer with us to either confirm or reject your hypothesis, or your understanding of his possible interpretation of the situation.
How is it in your mind that the developer and manufacturer of said equipment doesn't know how it works?
On what evidence are you expecting Lionel to be wrong?
For nearly all of us, with apparently the exception of you, if we unhook the connection from the binding post to the outside rail, or the connection to the earth ground at the wall, we get a flickering headlight, and poor operation, if any operation at all.
The effect of these disconnections can be easily tested, and has been, by many, many people, as John has correctly implied.
As I mentioned, and tried to explain, there's a small chance that your original connection approach might still work for you, but not likely for many others, if any at all.
You're the lone guinea pig. We need more evidence on order to be persuaded. Can you provide it?
Mike
Mike: I shall review my 4" stack of correspondence between me & Dale, me & Jim Rohde (Lionel's most senior e-guy), and me and Jon Z (Lionel's VP of technology or similar), and then get back to you.......
Phil, I'll bet big money that Jon Z. isn't going to suggest disconnecting the track signal because it's "not needed". It boggles my mind that we are even having this conversation. 
Since I worked with Dale on the TMCC Buffer, and we had many discussions about TMCC/Legacy signals, I am positive he never took that position! Where do you come up with this stuff? 
I find it interesting that on the Lionel ZWL transformer, they designed it to have a direct connection from Legacy command base to transformer. Not sure why they would do that if some form of connection isn’t necessary. Click for larger view.
Ted, the plain facts are that it is an essential connection, no amount of mis-information will change that.
@gunrunnerjohn posted:Ted, the plain facts are that it is an essential connection, no amount of mis-information will change that.
Yup, agree. That’s where mine is connected.
@TedW posted:Yup, agree. That’s where mine is connected.
I'm pretty sure that is just so the Command Base doesn't wander off. 
Guys: I just ingested a very large piece of HUMBLE PIE! It FINALLY dawned on me that my layout also employs Legacy....who's base, CB-2, DOES INDEED connect CB-1 to the outside rail...via its connection to CB-2!! I apologize. [My only excuse would be that I rarely use CB -2.]
I think this is where we all say in unison: I told you so!
@phil gresho posted:Guys: I just ingested a very large piece of HUMBLE PIE! It FINALLY dawned on me that my layout also employs Legacy....who's base, CB-2, DOES INDEED connect CB-1 to the outside rail...via its connection to CB-2!! I apologize. [My only excuse would be that I rarely use CB -2.]
I'm pleased that this wasn't just a troll. Mistakes are how we learn and refresh...ours and others too.
Except for Einstein...he thought he was wrong, but he was right. Oh well...
And thanks for the update on the setup.
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