Spireblade Posted January 30, 2017 Share Posted January 30, 2017 I wanting to convert an old Hornby Evening Star that has a tender drive. I fitted the basic R8247 but it's a bit jumpy and keeps stopping briefly. All wheels etc are clean. It ran very smoothly as DC. Will fitting a better decoder be of any benefit? Link to comment Share on other sites More sharing options...
96RAF Posted January 30, 2017 Share Posted January 30, 2017 Presume you mean R8249 decoder not R8247 acc decoder which would be a challenge fitting even to a tender.The reason the loco keeps stopping is probably because the decoder is self protecting and cutting out.The other Hornby decoder - Sapphire is much more adjustable but much more expensive. Other makes of decoder are available but we are not allowed to promote them on here. Link to comment Share on other sites More sharing options...
Spireblade Posted January 30, 2017 Author Share Posted January 30, 2017 errr.....yes, the 8249. :-)I thought I would ask before I take it off to the local DCC specialist and told that I need to spend squillions on this or that decoder.However, I'll take your advice, as I haven't ever used another type of decoder, mainly for fear of blowing one up! (disasters are my speciality) Cheers Link to comment Share on other sites More sharing options...
2e0dtoeric Posted January 30, 2017 Share Posted January 30, 2017 Older (tender-drive) loco's take more power than the cheapo decoders can deliver, so the decoder turns itself off so it doesn't get fried.Look for a decoder that can deliver 1 amp (or more) on the motor outlet wires. Link to comment Share on other sites More sharing options...
96RAF Posted January 30, 2017 Share Posted January 30, 2017 Have a look at the other posts about older model power requirements.I'm sure Evening Star ringfield tender drive was listed. Link to comment Share on other sites More sharing options...
Spireblade Posted January 30, 2017 Author Share Posted January 30, 2017 Will do. Cheers Raf Link to comment Share on other sites More sharing options...
The son of Triangman Posted January 31, 2017 Share Posted January 31, 2017 Another reason for cutting out nay be a short circuit. Do you have the Hornby loco box? If so what model number is it as Evening Star has carried several numbers in the catalouges over the years and there are several motor versions for the tender drive and a direct drive motor. MK2 ringfield motors for instance have a continutity cast pin that makes contact with one brush holder/contact, this version also has a black continuity wire. Most people remove the wire but forget to insulate the contact that touches the cast pin. Link to comment Share on other sites More sharing options...
Spireblade Posted January 31, 2017 Author Share Posted January 31, 2017 Hmmm.... I don't have a clue! I bought it on Ebay and it came without a box.If it helps, it is the motor with the black wire spade type connectors that slide onto the motor body. I haven@T tampered with anything but the black and red wires. Link to comment Share on other sites More sharing options...
The son of Triangman Posted January 31, 2017 Share Posted January 31, 2017 Sounds like a type 2 ringfield, could be a short with the cast chassis pin that makes contact with one brush holder/contact, any chance of a few pictures of the installation? Link to comment Share on other sites More sharing options...
Spireblade Posted January 31, 2017 Author Share Posted January 31, 2017 /media/tinymce_upload/30b4197d1d07fe73d8a43c39e6701589.jpg Link to comment Share on other sites More sharing options...
The son of Triangman Posted January 31, 2017 Share Posted January 31, 2017 R.066 Duchess motor with type 2 ringfield with cast pin, converted to DCC. /media/tinymce_upload/d53acc6e9e9d2533fe3d0108b967b901.jpg/media/tinymce_upload/57bfe80671c3b4e59df999fe109454bf.jpg Link to comment Share on other sites More sharing options...
Spireblade Posted January 31, 2017 Author Share Posted January 31, 2017 Tried uploading a pic, I might work 😛 in fact, it's now there. However it does look different as in the contact is pointing at a "10 o'clock" angle and nowhere near the cast pin. As I have taken the Hornby decoder off it is just the wires that were originally cut. Link to comment Share on other sites More sharing options...
The son of Triangman Posted January 31, 2017 Share Posted January 31, 2017 Same type of motor. Decoder red wire goes to the red wire running from the tender pin, the Black decoder wire runs to the black wire pushed onto the casting on the left. The left contact tab wire needs taking off and the metal tab insulating, solder the orange decoder wire to the main left hand brush contact itself and the grey wire to the other brush contact. That's basically it for the installation. If the decoder is still tripping then there is a short somewhere else or the current draw of the motor is exceeding the decoders stall current limit. Link to comment Share on other sites More sharing options...
Spireblade Posted January 31, 2017 Author Share Posted January 31, 2017 So would you recommend a beefier decoder than the R8249 for this type? Link to comment Share on other sites More sharing options...
The son of Triangman Posted January 31, 2017 Share Posted January 31, 2017 All depends on the stall current of the motor. Normally a normal Hornby decoder is fine for this motor, however as the motor gets older the magnet tends to loose magnetism and the current draw goes up, if it goes beyond the decoders current limit then the decoder will either fry or shut down if protected by it's software and circuitry. If the magnet is weak then it is best remagnetised or replaced as otherwise it will eventually cause the coils of the armature to heat up and fail. Hattons do a very nice inexpensive 8 pin decoder with harness capable of taking up to 1 Amp in power should you wish to try a beefier decoder. Link to comment Share on other sites More sharing options...
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