RailPro > RailPro Specific Help & Discussion
Really strange problem / fix
Dean:
I just installed a new LM-3 into a new Stewart/Kato F7. The install went fine. But during testing, my HC kept losing contact with the LM-3. The engine never hiccuped, the loss of radio signal could happen anywhere on my layout. It even dropped out when I was standing less than 2' away from the engine. ( imagine if you can a fat, bald old guy trying to chase down a run-a-way engine ;D )
I checked the install and found nothing wrong. After an hour of checking and testing the only thing I could think of was where the LM-3 was installed. It was pressed down against the two wires coming from the rear truck. ( they were covered with shrink tubing ) I postulated that the LM-3 was getting radio interference from the AC track voltage that DCC uses. I taped a thin piece of lead to the bottom of the LM-3 and reinstalled it. Problem solved. The engine ran for over an hour without any problems.
Strange, really strange.
Dean
Alan:
Doesn't surprise me. There is no difference between a wire and an antenna. Twisting the wires may eliminate the problem in the future.
The LM2 has a RF shield built in. Your problem may be a consequence of the shield being dropped from the LM3.
Dean:
Thanks for the information. I was wondering why I didn't have any problems with installing LM-2s in identical engines.
KPack:
I had no idea the RF shield was dropped from the LM-3. Did Tim determine that it wasn't necessary or was he looking for more space?
-Kevin
Alan:
I don't own any LM3, LM3S or LM2S. My fleet is solely LM2. Basing on Tim's earlier comment.
--- Quote from: G8B4Life on December 28, 2017, 07:12:01 AM ---Interesting, the LM-2S's (and 3S's) I have don't have what looks like a shield over the RF circuit board as Alans does. Wonder why it was dispensed with?
Perhaps Alan can chime in, I wonder if the temp sensing works properly without the unit be contained in the case?
- Tim
--- End quote ---
Navigation
[0] Message Index
[#] Next page
Go to full version