any idea with this please

[dtb]

Hornby M7

The loco is still DC but has a strange behavior, see vid link below.
The loco was acting normally in forward and reverse using a old H&M Clipper, however just received a new Gaugemaster Combi today and whilst the loco runs normally in reverse seems it can't make up it's mind when attempting forward running.

https://youtu.be/nEjJS_jXwKE

Thanks

[sandy]

Does the new controller work propperly with other locos. If not I would send it back to Gaugemaster. Is it Ebay new or New new.

[dtb]

Does the new controller work properly with other locos. If not I would send it back to Gaugemaster. Is it Ebay new or New new.

It's a brand new controller from online retailer which arrived today, as it is cold in the attic I set up a basic DC test track on the dining room table to test the M7 prior to DCC decoder fitting, fortunately I had another recent purchase nearby, a Tri-ang Hornby BoB Winston Churchill. The Churchill does not show the same problem as the M7.

As all my other loco's are DCC fitted and I have probably switch off DC running I will have to get some other Tri-ang and Dublo loco's to test and establish the controller is not at fault.

Decoder fitting an M7 I believe is a bit of a pig as one of the side weights has to be removed (said weight being stuck with glue or double sided tape at the factory). So I will test with a decoder and test prior to messing with the above and if all is ok I'll just accept it. I also have the option to test the loco in the attic on the DC test track which uses a Gaugemaster 100? single panel mount controller. I have options just wondered if anyone has had the same that could nail the answer.

Combi cost me £41 and the loco £74 so no major costs involved, just curious as to what the issue could be as I have not experienced this strange behavior before in many years.

[sandy]

Sorry I cant help. it looks as if the controller is OK. Gaugemaster controllers are normally very reliable I have used them for years. I do not have a clue about DCC all my layouts have been DC.
Why dont you give Hornby a ring maybe they have had the problem before. It sounds an electronic problem to me. I expect somebody else will be along with some help soon who knows more about electronics.

[Brian]

Its running quite fast. Is the speed knob turned up high? If so, what happens at very low speed settings?

Personally, I would suspect the GM Combi as it uses PWM for motor control, where as the old H & M Clipper controller uses simple rectified AC and a resistance mat for speed.

If you have a multimeter set it to DC volts of 20 or more, connect is across the rails then place the loco on the test rails and retest it. If it shows the same hunting symptoms, look for the multimeter showing any changing polarity (rapidly). If the meter remains constant then its the loco, if is swaps polarity is the controller.

[RAF96]

Does it do the same if you turn the loco round on track or does the problem now affect the other direction. That would point firmly to the loco (snag is in same loco direction) or the controller (snag is in same track direction).

[dtb]

Took it to the attic earlier and used my other test track which uses a Gaugemaster 100 panel mount controller and the very same thing happens.

Yes RAF96 it acts in the same way, loco only runs well in reverse whichever ways it is pointing.

I used Brian's advice using a meter and the display was constant so the fault appears to be with the loco, I expect some fault with the pcb maybe?
Or a faulty blanking plug possibly, I could check that perhaps but I don't fancy putting in a decoder just in case it shorts out and ruins it, I've got the T-Shirt for that one!

Thanks for all your input

here is another short https://youtu.be/urfsr59hvSE on the other test track.

[Mountain Goat]

It almost sounds as if it has a DCC decoder onboard already...

Strange!

[dtb]

So if I place on the test track using DCC 'prog' mode to read the decoder (if fitted) what will happen if it doesn't have a decoder. Apart from not getting a reading will the voltage applied create any issues?

Thanks

[Rog (RJ)]

Putting it on a programming track won't cause any problems.