tts class 47 sound decoder

[bazjones1711]

hello all ,hope someone out there can help us please , my son having bought a Bachmann class 47 , now wants to put a Hornby tts sound chip in , so having purchased   a sound chip which is 8 pin this now needed a 21 pin to 8 pin adapter , so then sent off for one of these , all we had to do was plug the 8 pin into the adapter and plug the 21 pin onto the loco pcb board , that is all fine , tested the loco out and all works fine , now to the problem  , when the body is put back on the top of the tts 8 pin is to high so the body will not go back on , ok its only a few mm but enough , so what are the options , would buying this type of 21 pin socket then soldering the 8 wires from the tts decoder to pins 1 to 8 marked up work  , i live in hope

regards Baz

Edited August 4, 2019 by bazjones1711

[Paul80]

That should work just fine

 

I would also think about adding something like a 500 ohm to 1kohm resistor to the blue wire as Bachmann lighting circuits are known to overload TTS decoders.

 

Other than than you should be good to go with that adaptor.

 

Paul

[Bob83a]

NO, do not solder the TTS wires to numbers 1 to 8 as marked on the board. The pins on 21 pin sockets are in a different order to those on the 8 pin plug and also the required connections are spread over the 21 pins.

 

I am sure someone can provide a list of the connections that are necessary.

[mezzoman253]

Hi, This topic may help you  

 

Rob

 

[RobjUK]

This should give you the info you need:

 

A Bachmann (47, I think) 21 pin connector showing added wires for a hard-wired decoder change:

 

 

 

The 21 pin connector pin - signal table; you can see the wire colours match the above photo:

 

 

And the Hornby TTS decoder info. Whether you connect it to the adapter board you show, or solder direct as in the first photo, is up to you.

 

https://www.islandrailways.co.uk/knowledgebase/tag/tts-sound/

 

 

[Chrisr40]

I have a vague recollection that road and rails do a low profile adaptor. Could be wrong but worth  Google. 

 

https://roads-and-rails.co.uk/store/p90/Super_Slim_8_to_21_Pin_DCC_Adaptor.html#

Edited August 5, 2019 by Chrisr40
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[mezzoman253]

13 hours ago, Chrisr40 said:

I have a vague recollection that road and rails do a low profile adaptor. Could be wrong but worth  Google. 

 

https://roads-and-rails.co.uk/store/p90/Super_Slim_8_to_21_Pin_DCC_Adaptor.html#

If that slim one doesn't work, you can unsolder the 8 pin socket and solder the leads of an 8 pin wired socket to the vacant holes and plug your TTS decoded into that. It works, as that's how I did my Bachmann 47.

 

HTH

 

Rob