Welcome to South West Digital Ltd  


Please do NOT post items to us on a Friday as there is no one here to accept it over the weekend.  This will cause a  delay in processing your order / replacement.













  We have moved

Please note we moved address over a year ago from

202a High St
BS22 6JD
South West Digital Ltd
C/O 47 Merlin Park
BS20 8RJ
Tel: +44 (0) 1934 515382  
Mon – Thurs  09:00 – 16:00hrs,
Closed 13:00 - 14:00hrs
Fri 0900 - 1300 hrs

Email: info@swd4esu.co.uk


12/04/19 LS v5 English Manual download

Adapter Board English Translation download

26/3/19 LS v5 English Quick Start Guide available for download
13/03/19 LokSound v5 micros all pin configurations delayed until April

Please note there are No English manuals available at this time for the new v5 range of decoders.

28/01/19 LokProgrammer V5 Software available for download

LokSound 5 Decoder Family


 Please note we do NOT yet have stock.  This is due in from mid Feb onwards.

Our 5th generation of LokSound has been re-developed from scratch again. Thanks to a high performance, 32-Bit microcontroller, we have been able to improve all key features again: LokSound 5 decoders will support up to 10 simultaneous sound channels. Each channel will reach HiFi-Quality level thanks to 16 Bit Resolution and 31250 Hz sample frequency. LokSound 5 decoders will bring your model trains to the next level and sound almost like the original. A 128 Mbit flash memory chip allows for enough capacity to hold the sounds.  (Approx 8.5 min at 16 Bit, 31250 Hz)
LokSound 5 decoders offer an advanced B-EMF load control that runs with up to 50 kHz base frequency and is optimized for low-noise operation. This is important for coreless motors such as Faulhaber or Maxon and also for Large scale locomotives.  Every LokSound 5 decoder comes with plenty of function outputs and can control servos or SUSI-modules if needed.
Every LokSound 5 decoder is a true Quad-Mode Decoder that talks DCC with RailComPlus and M4 and will be automatically registered with Märklin® command stations. As these decoders do also support Motorola® and Selectrix®, they can be used also with older Digital Command Stations. Even better, every LokSound 5 decoder could also be used with Analog DC or Analog AC controllers (even the small N scale decoder!)
Based on the command station, up to 32 function buttons are supported that can be mapped to any output due to our superior ESU function mapping. Three brake functions and a two-stage load simulation will let you enjoy your model railroad even more.
We will offer several LokSound 5 decoder versions:

Further technical information to follow.

New Prices announced for 2019

We have moved from our offices in Weston super Mare to our home in Portishead.  Any mail will be redirected for a year.
South West Digital Ltd
C/O 47 Merlin Park
BS20 8RJ
01275 849496
01934 515382
(We are NOT a shop. Mail order ONLY, NO personal callers)


Mobile II 50113, 50114 are now back in stock and available through our Dealer network or direct from ourselves.

ESU Launch New Braking feature for the UK's Favourite decoder.




The New Dynamic Brake feature is available with a firmware update through the LokProgrammer 4.6.2. Download Here
Changes made to the existing Dynamic Brake by adding a New CV 179 as an addition to CV 4 now offers two types of Braking with even more realism. The stopping distance required can be achieved with practice by reducing the throttle to zero and pulsing the F Key when slowing to a stop.  This gives a very nice play feature to the ESU V4 decoder range.
Option 1 (Fail-safe using a latched F Key)
Extended Brake         (CV 179 > CV 4)
Light Engine   When the throttle is reduced to zero and the ‘Dynamic brake’ is OFF the loco stops, using a suggested mid-point value in CV 4 as normal. 
Heavy Train   Press F Key ON to Enable.  With the ‘Dynamic brake’ ON, the loco now stops using a suggested high value in CV 179.  The higher the value, the more the loco will run on.
When stopping Press F Key OFF to Brake then ON again to enable.
Option 2 (For the professional driver using a momentary F Key)
Dynamic Brake          (CV 4 > CV 179)
When the throttle is reduced to zero and the ‘Dynamic brake’ is OFF the loco stops, using a suggested high value in CV 4.  With the ‘Dynamic brake’ ON, the loco stops using the reduced value in CV 179.  The lower the value, the harder the braking effect will be.  Press F Key ON to Brake then OFF to release.
1)         Differences in both CVs  4 and 179 values (0-255) along with Motor / Gearbox combinations will have an effect on the overall Braking experience.
2)         LokSound V4 brake sound thresholds CVs  64, 65 may have to be reduced by 2 digits after setting up the ‘Brake’ To allow for the new stopping distance.
" Not just here for sound, ESU offer a full range of products for the complete DCC experience"


12/9/17 Please be advised that the new Hornby TTS decoders will FAIL when used with RailCom enabled dcc systems.  The older TTS decoders were more tolerable of the RailCom cutout signal so would run.  Please note this is NOT an ESU issue and all concerns should be directed at Hornby customer service.
04/09/17 Due to the falling pound against the Euro we have had to increase our prices.
  If using JMRI Decoder Pro, please make sure you install v 3.7.7 as per JMRI Release notes in order to make changes to ESU v4 decoders.

Exciting new sound algorithm from SWD

Customer feedback has always been very important to us.  What has become apparent, is the need to make the sound decoders more responsive, thereby allowing you the modeller, full use of our project features regardless of layout size. The end result is our unique UDRIVEalgorithm.  During testing, ESU were very complementary on our new structure and the innovative use of their software, as we continue to push the boundaries to a whole new level.

The first SWD UDRIVEdecoders were launched at the 2013 Warley exhibition.  These were enthusiastically received by all who heard and tried them, and are progressing into an exciting new range of both Diesel and Steam projects.  Gradually, all of the remaining SWD sound library will be upgraded to UDRIVEas well as new ones added, for which there are many already recorded.   Please see the British Sounds page on our website for latest releases.

For those of you, who already own ESU V4 decoders and wish to take advantage of the very latest SWD features, please contact us for details of our reprogramming service. 

This progress is the most exciting recent development to have taken place in the field of DCC model locomotive sound control.   Now you can enjoy features such as, Multi-Start, Fade In and Out on the move, Playable horns / whistles, Light & Heavy chuffs to name but a few.  As such, listening and operating your model, loaded with UDRIVE, together with the very best British locomotive sounds available is uncannily real!

Try UDRIVE’ from SWD today – you’ll be amazed at what you’ve been missing!


 “We create – UDRIVE


Available through our supported dealer network or direct from SWD.


Copyright © SWD Ltd 2019