Fitting Hornby R7147 DCC to R3854X Princess Royal Class

[Lynrob]

Hi all, having a problem fitting DCC sound chip to my LMS Princess Royal class Dutchess of Kent. the speaker that came with the Hornby Decoder seems to be to big, Rubs on the centre wheels when fitted in the tender as per instructions. Has anybody else had the same problem, thanks Regards Robin

[ColinB]

I know this is an issue as it has been reported before. If you look at my posts you will see how often than I complain that the Hornby speaker fittings are generally not fit for purpose. I think this one when you screw down the plate to hold it, it is under tension which is not right. What I do is replace the normal Hornby Speaker with a small iphone one available from "Road and Rails". It also sounds better.

[96RAF]

Known problem on some tenders, which is easily fixed with an insulating gasket of some sort. I used a suitable O ring.

[ColinB]

You'll be pleased to know Hornby have fixed this issue on the Thompson A2 and the new Merchant Navy, so obviously they do listen. For once, I did use the supplied speaker with both of these models.

[Lynrob]

Hi 96 RAF thank you for your solution to the problem of the speaker being to large. I am not sure where you put the o rings in the tender to solve the problem if you could elaborate a bit would be appreciated.I am faily new to all this, I thought that if I purchased a train with DCC fitted it already had sound, but unfortunately it doesn't so had to purchase another decoder. Regards Robin

[Lynrob]

Hi Colin B, thank you for your reply rot my problem with the speaker being to large for the tender, I will have a look on line hear in Australia and see if I can purchase a smaller speaker locally if not will get one sent from the place you suggested, had a look at there web site, there is nothing locally where we live. Regards Robin

[96RAF]

@Robin

I bought a selection box of O rings from a local hardware store primarily to replace traction tyres that were unavailable at the time.

Fortunately one of the rings was the same size as the standard TTS speaker rim so I simply stuck it on with UHU avoiding the speaker diaphragm obviously. The speaker was then placed into the recess and nicked slightly where the wheel flange touched.

My initial problem was the speaker flange was bridging across the tender wheels and creating a short.

If you can get hold of them, iphone speakers or cubes are a good replacement for TTS but make sure they are 8 ohm impedence and capable of handling 1 watt.

DCC-Ready means the loco has a socket for you to fit a decoder of your choice in. This can be a basic decoder or a sound decoder.

DCC-Fitted means the loco has a factory fit basic decoder installed. If you want sound you have to replace the basic decoder with a sound decoder and speaker.

DCC-Sound means the loco has a sound decoder fitted. Different manufacturers denote this in different ways e.g. Hornby early sound fitted locos were designated by an XS suffix to the catalogue number. Current sound fitted locos are designated by the TTS suffix.

Bachmann uses a DS suffix to denote factory fitted digital sound.

[Lynrob]

Thank you very much for the advise 96RAF and ColinB it is much appreciated. I was fiddling with the speaker that came with the Hornby Decoder and fond that if I double sided taped it under the coal in the tender it worked, and the sound is fine, not sure how long it will last just taped there but it's ok. Thanks again, till next time. Take care and stay safe, Regards Robin