David-349920

Thanks Paul. Just found this described in the manual. ABC braking is not supported in non-sound either so perhaps it’s all a bit academic. It would make sense for Hornby to implement CV12 in non-sound decoders to give consistency across the range.

I used a DVR8871 (3.5amps peak and a few quid on eBay) but I was only powering one loco. I assumed that on a full layout that you’d use a power booster but also wondered about using several small H bridges around a layout broken down into sections - the layout would have sections anyway if you were using ABC braking. Not looked at non sound decoders but do you not set them up to be either Bluetooth or track based DCC in the same way that I did with a sound decoder? Only using one carriage return this time. Let’s see if it looks better!

OK, so I’ve found out. I built a simple square wave generator using a NE555 timer chip. The frequency was about 8.5khz ( a continuous stream of 0s in DCC terms would be 8.62khz I believe). This drove an H bridge motor driver which in turn powered a rolling road. Using my Mallard locomotive equipped with a HM7000 I observed the following:- 1/ the loco was under full Bluetooth control and the square wave power had no effect on this control. 2/ using the standard 5 diode network to generate an asymmetrical square wave similar to that in the manual, the loco behaved as it should dependant on the relevant cv settings as described in the manual. So it is possible to use ABC braking without a true DCC signal being present on the track. A simple square wave can be used which saves all the complexity of a DCC controller. Perhaps someone else might like to repeat the experiment to confirm my findings, but personally I’m happy with the results.

Using different words, you more or less repeated what I said - ABC won’t work on a dc network and requires a DCC signal to be present. The famous manual shows this clearly, the signal being a “square wave” albeit with 1s and 0s having different periods. When using the diode network it is the asymmetry generated (rather than the data in the signal) which is detected. What I’m suggesting is that it may be possible to use a simple square wave and diode network to produce an asymmetric signal which might trigger ABC braking. Perhaps there’s only one way to find out…….

Hi. I’ve seen several mentions on here regarding the use of ABC braking with the HM7000 series of decoders. It has been pointed out that ABC requires a DCC signal to be present on the track for it to work. So this useful feature cannot be utilised on a dc layout. Am I correct in assuming that in ABC the asymmetry is detected as a small shift in the dc level once the signal is rectified in the decoder. This being the case it should be possible to “trick” the decoders by using a simple square wave on the track (ie not full DCC with its inherent cost and complexity). The usual diode network required for ABC would then be used in the usual way. Just a thought!

Thank you for various responses. Following a power cycle of both decoder and Android phone, I have managed to link them. No agitation before, during or after! Prior to my original post I spent quite some time trawling the forum and using various search criteria to see if I could find the answer. Without success. Since sorting my problem have found 1 answer (from Steve??) and that took a while to find. The Forum is useful but it is essentially a random collection of unconnected questions and answers so it can take time to find what you are looking for. It is undoubtedly quicker just to start a new thread and hope someone helps. Thanks again.

Somehow I knew this wouldn’t be simple! To unlink the iPad I had to first unassign the locomotive then use the Unlink and Delete button. iPad can no longer “see” locomotive. On opening the app on the Android phone it says “No Linked Devices” and invites me to “Link Device” then to “Start Scan”. The list of resettable devices shows my decoder which I click on. I then have to enter Reset Passcode which I do and then have to power cycle the locomotive (power bank installed so this takes 60 secs). I then get “Device Reset” message and “To dismiss, please restart scan” - no other options. I am then given the Ready to link page which shows the same list of resettable devices (only my decoder). I’ve been through this loop half a dozen times and I still have “No Linked Devices”. I am able to link (re link) the decoder to the iPad but just can’t get it to work with phone (Samsung Galaxy A21s). Anyone got any ideas? Cheers

Thanks for the response. I only intend to use one device - an Android phone. I’ve changed the profile which went very smoothly. I’ve also been studying the Full Reference Manual and, whilst it describes linking devices, I am unable to find anything about unlinking. Checking the app, there are two buttons on the manage profile screen which I guess might be appropriate:- 1/The first allows a locomotive to be unassigned which I’ve tried in which case the iPad will no longer control the locomotive. This is easily reversed by using the assign button. 2/ The second is the “Unlink & Delete” button. Does this just remove the locomotive from the iPad without making changes to the decoder - just worried about the delete bit and haven’t tried it! Cheers and thanks again.

I’ve installed 8pin sound decoder in A4 Mallard and been controlling it via an iPad. Been very pleased so far although it’s been running with A1/A3 profile. I note that an A4 profile is now available for OO and plan to download it. However I also want to run the app from an Android phone now that this version is ready. What steps should I take and should I change the sound profile to A4 before or after moving from iPad to Android.

I’ve done this. Bit of a squeeze but decoder, power bank and speaker all fitted and all works well. There’s a thread somewhere on here with pictures. Good luck.

Actually looked at HM6000 manual a found that OTA is implied, though not explicitly stated. So that would probably mean that using the HM6000 app with a HM7000 decoder does not wipe out its OTA capability. Thanks for your responses and sorry for my red herring.

“The only cure is a bottom up reload using a specific Toolbox developer app, but again these loads are OTA.” If my assumption that the OTA code gets removed when the HM6000 app (which presumably doesn’t have or even need OTA functionality) then even Hornby would not be able to use OTA for reloads. I assume they must have hardwired mechanism for doing this.

Been exercising the old grey matter regarding the use of the wrong app (HM6000) and ending up with a seemingly useless decoder. It may be totally irrelevant but I’ve had a similar experience with Over The Air (OTA) updates albeit in a WiFi environment. Part of the code will be dedicated to the OTA functionality and when an update happens all the code (inc OTA bit) gets overwritten so the updated code has to include the OTA code. Clearly the HM7000 can be updated with HM6000 code and if this is done, OTA functionality will be lost. Since the HM7000 can work in DCC mode (ie without Bluetooth) might it be possible to update the code from new app without Bluetooth (making sure it’s turned off in the iPad). This may be how Hornby install the default profile in the first place. Having successfully installed a HM7000 and got it working, I have no inclination to try this out but if you’ve now got a non worker because you updated with HM6000 code it may be worth a try - what have you got to lose?

Thanks guys. Tape no longer around decoder. With speaker box underneath and decoder harness taped down it isn’t necessary anyway.

Thanks raf. A4 for OO doesn’t show when you browse profiles in the app. Are other profiles available to download? Otherwise I think, for the time being, I’ll leave well alone.

Installed 8 pin sound decoder in A4 Mallard (R3371). Using a rolling road I started with the decoder and speaker hanging loose and all was well until I tried downloading a new profile. Kept being told that sound data was missing. Had another go after good night’s sleep and it’s now working albeit with A1/A3 profile. There isn’t OO gauge A4 profile - would the TT version be ok? Getting decoder, speaker, and power bank properly installed was a squeeze - power bank sits on small shelf at front, speaker box (2nd smallest) over DCC socket, and decoder on top. Tested all the basic functions and I’m very pleased with results. Still lots to play with in the app though. Bluetooth range seems pretty good - I can control locomotive from a good 6m away. I reckon Hornby have got a real winner.