Fitting HM7000 into J83 (or Jinty)

[john_ruddy]

I am looking at fitting a HM7000 decoder into a DCC fitted J83 - this has the same chassis as the Jinty (and possibly other 0-6-0s). This is a 4 pin socket, so I'll be hard wiring the decoder in place.

Has anyone done this and found space for speaker and stay alive as well within the J83? The extra length of the decoder is making me think twice about this. Any tips from people who've tried?

[Brew Man]

If you're unsure why try just fitting the parts in place before doing any soldering.

[Fishmanoz]

Searched the forum to see if an anyone had reported doing it previously. Nothing found. 

And doesn’t appear in this thread with content on successful fits: 

 

[George-351466]

I experimented with an 8 pin HM 7000 decoder in a J83 some months ago. Hot wiring the chip into the motor is straight forward, but I recommend leaving at least 1” of wiring on the plug end, so it can be reconnected for future use on a dcc model if desired. I didn’t do this and had to buy some 8 pin extensions cables with plugs when I decided to use the decoder on something else.

As for the conversion itself; the decoder can be fitted under the loco body ok., but the speaker will have to go in the cab where there’s plenty of room for a small cube, plus power point (below speaker) if you don’t mind filling the cab space. 

That all said, I abandoned the conversion after encountering what has become an irritatingly common problem. Namely: connection is made and sounds work, but the loco stuttered for a couple of seconds and then failed. The decoder disconnected from the app and it took about 30 seconds for reconnection with the same result. I don’t know why this happens, but have experienced it on a couple of other attempts at adapting older locos - including (today) a Merchant Navy Class. Both this, and the J83 are smooth, quiet performers in dc mode, so there are no motor issues. The Merchant Navy model is just before it was issued dcc ready, so I can’t see what’s preventing success. 

Most frustrating. Anyway, it can be done in a J83 / Jinty et al; I’m just not doing something right, even though my cd converted Limas work fine with HM7000 decoders.