Some engines display a weak signal on certain spots on a layout. Why does placing your hand over the engine improve the signal reception to the engine.
Rod Miller
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The TMCC signal is made up of essentially 2 parts. The track signal and the house earth ground signal. This is the portion of the signal that uses the house ground that the locomotives antenna pick up. By placing your hand near the locomotive you basically enhancing the earth ground half of the signal to the locomotive.
Things to make sure of is that the Legacy / TMCC base is plugged into a known properly wired grounded outlet. It's preferable not to use a power strip that has surge protection as sometimes these disrupt the ground half of the signal. Also pin 5 of the serial connection on the base provides the same ground side of the signal. A wire from either from a ground point on a receptacle or pin 5 laid near but not connected to the trouble area will also boost this portion of the signal.
Thank you.
The hand-over-tender trick verifies there is a signal reception problem with the tender antenna setup. We resolved two like this using Kapton tape and nylon screws and washers to re-isolate the tender from the frame, and it worked wonderfully! Superior signal reception, all the way across the layout, with the antenna on the handheld down.
romiller49 posted:Some engines display a weak signal on certain spots on a layout. Why does placing your hand over the engine improve the signal reception to the engine.
Rod Miller
what system are you running?
you might have a ground plane issue.
I have legacy. I have one spot on layout where one track goes under another. All engines work fine except one tmcc engine and one legacy engine have weak signal reception at the lower track.
Rod Miller
romiller49 posted:I have legacy. I have one spot on layout where one track goes under another. All engines work fine except one tmcc engine and one legacy engine have weak signal reception at the lower track.
Rod Miller
That would definitely be a candidate for a ground plane wire. Usually run it under the upper track.
romiller49 posted:I have legacy. I have one spot on layout where one track goes under another. All engines work fine except one tmcc engine and one legacy engine have weak signal reception at the lower track.
Rod Miller
take a wire about 16 or 14 gauge run it along the area where the signal is weak. then continue to run the wire to the closest electrical outlet and connect it to the center screw.
Kerrigan posted:Superior signal reception, all the way across the layout, with the antenna on the handheld down.
FYI, the antenna on the CAB1 has nothing to do with the strength of the track signal. The only thing the antenna on the CAB1 is for is to communicate with the command base. The command base generates the track signal.
Ran a wire under the upper level problem area and attached it to the cover plate screw on an outlet and solved the weak signal. All is fine now. Thank you all for the help.
Rod Miller
We love a happy ending Ron. 
BTW, when you're running these ground wires, any size wire is suitable. It doesn't carry any current, so #30 wire-wrap wire would work just as well as #12 wire.
bigdodgetrain posted:romiller49 posted:I have legacy. I have one spot on layout where one track goes under another. All engines work fine except one tmcc engine and one legacy engine have weak signal reception at the lower track.
Rod Miller
take a wire about 16 or 14 gauge run it along the area where the signal is weak. then continue to run the wire to the closest electrical outlet and connect it to the center screw.
Using the electrical outlet for ground can be a problem when the service pipe to the house is plastic from the shutoff valve to the meter, in older homes. Driving your own ground rod outside the home by the layout room, and connecting it to your independent layout ground (like for the TMCC ground plane) is a far better positive ground. Provides a grounding loop isolated from anything else. A pure grounding.
Unless the builder never heard of the National Electrical Code, there MUST be a grounding rod for any installation. I have a plastic pipe from the meter as well, and there's a nice big grounding rod driven in next to the meter box.
gunrunnerjohn posted:Kerrigan posted:Superior signal reception, all the way across the layout, with the antenna on the handheld down.
FYI, the antenna on the CAB1 has nothing to do with the strength of the track signal. The only thing the antenna on the CAB1 is for is to communicate with the command base. The command base generates the track signal.
Thanks for the info John. Always wondered why some guys hold the antenna right over the tender, even touching it, to get it to receive the signal. Of course it's the hand holding it that is inducing the signal, if anything I'd guess.
Something happened on ours that it now works without the antenna pulled out. Used to have to extend it. All I've done in the past to change anything is adding TVS diodes to each side of the TIU. That couldn't have impacted anything. Another of those CL&W Ry mysteries.
Maybe I'm just generating TMCC signals ... :-)
gunrunnerjohn posted:Unless the builder never heard of the National Electrical Code, there MUST be a grounding rod for any installation. I have a plastic pipe from the meter as well, and there's a nice big grounding rod driven in next to the meter box.
We have one at the meter ... which is 50' from the train room. Thinking the added rod/etc would give the layout an isolated "pure" ground.
Can't hurt I guess, but I've never seen it be a problem in a properly grounded electrical system.
I believe by code all ground rods must be tied together if there is more than one rod.
Ken M
Bonding of Electrodes. A bonding jumper not smaller than 6 AWG copper or equivalent shall be connected between the grounding electrode and power grounding electrode system at the building or structure served where separate electrodes are used.
Length. The bonding conductor or grounding electrode conductor shall be as short as practicable. In one and two family dwellings, the bonding conductor or grounding electrode conductor shall be as short as practicable, not to exceed 6.0 m (20 ft) in length.
PLCProf posted:In my case at least, a ground plane connected to pin 5 is more effective than connecting to the house wiring.
Your mileage may vary.
I would expect that as all house wiring is not equal. You are basically going to the "source" at pin 5.
Ken M posted:I believe by code all ground rods must be tied together if there is more than one rod.
Ken M
A grounding rod which does nothing but provide the ground plane grounding, connect only to the layout, not to any house circuit, is outside of the electrical code, at least in Portland, Oregon.
That's undoubtedly true. However, consider that if you connect pin 5 of the Legacy adapter to the ground rod and perhaps your layout as well, you will be connecting the two grounds through the earth, any voltage differential will be seen by the Legacy base internally. Remember, the ground pin on the power adapter ends up connected to pin 5 of the serial port. Think of a lightning storm in the area...
I suggest you think carefully about doing stuff like this until you consider all the possible ramifications.
Kerrigan posted:bigdodgetrain posted:romiller49 posted:I have legacy. I have one spot on layout where one track goes under another. All engines work fine except one tmcc engine and one legacy engine have weak signal reception at the lower track.
Rod Miller
take a wire about 16 or 14 gauge run it along the area where the signal is weak. then continue to run the wire to the closest electrical outlet and connect it to the center screw.
Using the electrical outlet for ground can be a problem when the service pipe to the house is plastic from the shutoff valve to the meter, in older homes. Driving your own ground rod outside the home by the layout room, and connecting it to your independent layout ground (like for the TMCC ground plane) is a far better positive ground. Provides a grounding loop isolated from anything else. A pure grounding.
works at my house.
what kind of house do you live in?
bigdodgetrain posted:Kerrigan posted:bigdodgetrain posted:romiller49 posted:I have legacy. I have one spot on layout where one track goes under another. All engines work fine except one tmcc engine and one legacy engine have weak signal reception at the lower track.
Rod Miller
take a wire about 16 or 14 gauge run it along the area where the signal is weak. then continue to run the wire to the closest electrical outlet and connect it to the center screw.
Using the electrical outlet for ground can be a problem when the service pipe to the house is plastic from the shutoff valve to the meter, in older homes. Driving your own ground rod outside the home by the layout room, and connecting it to your independent layout ground (like for the TMCC ground plane) is a far better positive ground. Provides a grounding loop isolated from anything else. A pure grounding.
works at my house.
what kind of house do you live in?
Big 22 year old one.
There is some confusion as to what is required for the TMCC thru the air signal. What is required is simply a wire, either in the walls like the third wire electrical ground wire in the house or a wire distributed around the train room connected to pin #5 of the DE9 connector. They will end up being connected together thru the TMCC base/power supply/ line cord/ third wire ground. An additional ground rod is not needed or desired and violates code unless it is bonded to the single ground rod at the house electrical meter box. The only thing "ground" about it is that Lionel is using the third conductor ground wire in the house as an antenna. There is nothing "ground plane" about it. It's just a convenient wire to use as an antenna. If you didn't have a ground wire in your electrical wiring, a separate wire connected to pin #5 should work. I do feel however that the additional house ground wire in the walls and ceiling in the house probably helps the signal propagate and helps even though it may not be connected by using a 3 pin to 2 pin adapter. Some may have noticed that even though your engine may be sitting on an isolated section of track, not connected to the layout that has the TMCC base, the TMCC signal may still find it's way to that engine. I have to turn off the base to avoid the TMCC signal getting to an engine completely disconnected piece of track with it's own separate transformer. You cannot see the RF signal, but it propagates .
I do have some additional ground rods at the Ham Radio tower base and they are bonded as required with copper tubing to the house ground rod at the meter. They are for lightning protection only (hopefully).
cjack posted:There is some confusion as to what is required for the TMCC thru the air signal. What is required is simply a wire, either in the walls like the third wire electrical ground wire in the house or a wire distributed around the train room connected to pin #5 of the DE9 connector. They will end up being connected together thru the TMCC base/power supply/ line cord/ third wire ground. An additional ground rod is not needed or desired and violates code unless it is bonded to the single ground rod at the house electrical meter box. The only thing "ground" about it is that Lionel is using the third conductor ground wire in the house as an antenna. There is nothing "ground plane" about it. It's just a convenient wire to use as an antenna. If you didn't have a ground wire in your electrical wiring, a separate wire connected to pin #5 should work. I do feel however that the additional house ground wire in the walls and ceiling in the house probably helps the signal propagate and helps even though it may not be connected by using a 3 pin to 2 pin adapter. Some may have noticed that even though your engine may be sitting on an isolated section of track, not connected to the layout that has the TMCC base, the TMCC signal may still find it's way to that engine. I have to turn off the base to avoid the TMCC signal getting to an engine completely disconnected piece of track with it's own separate transformer. You cannot see the RF signal, but it propagates
I do have some additional ground rods at the Ham Radio tower base and they are bonded as required with copper tubing to the house ground rod at the meter. They are for lightning protection only (hopefully).
I'll hook the ground plane wire to the house grounding then and that should be good enough to "suck off the excess signal" from one track passing over another track ... correct?
I think of it more that the upper track tends to shield the engine on the lower track from the ground wire antenna signal. So connecting a wire to the pin #5 and placing it over the engine on the lower track, while under the upper track will allow the lower track engine to receive the necessary signal.
