Sly401

So far I have fitted 4 HM7000 decoders, one of which continues to give me trouble. Problem - Loco moves off smoothly until it reaches a certain speed , then it suddenly slows down to something like half its (pre hitch) speed if the control is set high then it accelerates smoothly all the way to the speed set. When decelerating it is smooth until it hits a particular speed ( I would say it is the same as when accelerating ) then it jumps up to around double its (pre hitch) speed. I can drive it smoothly and consistently if I keep the speed below the hitch point ( around speed step 60) but of course its all low speed stuff. If I drive it though the hitch its top speed seems slower than I would have thought Consistent hitch whether using App or NCE powercab DCC I observe an increase in amps on the NCE whenever it passes through the hitch Things I have tried, re-install profile install a different profile reset CV's Speed steps 28, 128, custom speed step table Motor tune (auto) Tried various emf and PWM settings Tried different start mid and High settings Fitted a different motor to the loco no difference Checked the idler gear not split, and motion smooth I had thought that this was something to do with shunting mode or brake function but not so sure now. This loco has the chip hard wired, does that invalidate the warranty ? Any ideas to try ? Thanks Paul G

Not seen this mentioned anywhere- I set the function button for the brake to toggle (the switch option) a week ago I had a problem and removed my loco from the track - this occurred when in shunting mode and the brake toggled ( I think) Next day I tried the loco and it was running very poorly, despite resetting all cv's then uninstalling the profile and even resetting the decoder the poor running (well it wouldn't run to all intents). Today I had another go - the brake function had been reset according to the app when I pressed the brake function key (not driving controls) the loco moved so I reset it to toggle and applied the brake function and the loco moved smoothly but slowly so putting 2and2 together I realised that the brake was on for the past week, and the toggle was effectively the other way round when the brake function is lit the brake is OFF and when it is not illuminated it is ON ( I was thinking I had a burned out motor). so as it was running albeit slowly I tried putting the shunting switch on and yep it now ran at a much better speed Took shunting mode OFF and back to slow speed So it appears that if you power off with a function engaged that setting then becomes the default and is working inversely Then there is the secondary issue that this was not cleared by a reset , uninstall and re-install of profile or even a hard reset using the password. Sly

Be interesting to know if the density increases as you get quite a bit lower temps getting nearer to zero C My own feeling is that it should as with your breath on a cold frosty day - but we will see Thanks for the reply Sly

Does the ambient temp have an effect on Steam (vapour) visibility ? Thoughts of enclosed layouts chilled down by an Ac Unit 🙂 Sly

Fitted to an oldish china super detail 8F R2449 as a first ever step into DCC. 8 pin decoder, I couldn't get the decoder and speaker in the loco so I removed the 8 pin socket and hard wired direct to motor and pickup leads. removing the socket ( I also cut down the 2 spigots that the socket fastened to) I could get a small speaker enclosure in the smokebox and the chip sat where the 8pin socket was. Had sound and some movement straight away but then things stopped working, I removed the profile and downloaded again and I got it working again, running was not good continually stopping. I set some CV's for speed ( start V) and gradually got some improvement swapped to Princess profile and things got better, I then ran the auto tune for the motor and it now runs superbly, sounds are good and control is silky smooth. Takeaways are If It stops working and you think you have blown it - delete profile and reload it may reset things Try different profiles if running is poor Run the motor tune it made a big difference to my 8F Sly