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Discussion Starter · #1 ·
Well I decided to buy something nice for christmas so I bought Hornby, two Royal Scots, two Patriots, one Britannia and one Stanier 4P. All were decoder fitted locos with Hornby's own decoders. As I have rubbished these decoders in the past I decided to give them a fair go and really see how they perform. I've been using DCC for nearly 25yrs from Hornby Zero One, CTC 16 and 32, Lenz, Wangrow System One, CVP Easy DCC and NCE Radio. I've built decoders, CTC 16, and used decoders from various manufacturers with varying results, some excellent, some good and some indifferent. But these Hornby decoders are ............. not good in fact they are attrocious. Any decoder that causes a loco to take off and shoot off the end of the programming track needs a rethink. I have yet to program one succesfully using NCE, System One , Decoder Pro and SrogII either on the programming track or on the main. Yet when I converted them to any other make of decoder, TCS, Lenz, ESU, Digitrax, CTE, NCE they program and run fine. So I decided to save one loco intact except for the RF supression cap which I removed and what do you know it programmed without running off and hitting the floor. So Hornby if you are going to continue to sell these decoder fitted locos remove the RF cap before it is sent to a reseller.
The decoder is still rubbish as the loco runs like a hairy goat so it got refitted with a TCS M1 and now it's as smooth as silk. Guess I'll be sticking to non DCC fitted locos from now on.

Rant over back to modelling.

Charles Emerson
Queensland
Australia
 

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Hi Charles like you I had some Hornby decoders in the past and had nothing but grief with them so into the box they went never to return, I have just received the new Hornby GNER HST fitted with decoders both in the power car and the trailer car and guess what no problems whatsoever I ran them out of the box and smooth control from very slow speed to top speed no hesitation just smooth as silk. One hour each way for a run in and now with a seven coach set and still no problems. Do you think I have a one off because I do.
Alan
 

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I think you will find that a lot of the older DCC Fitted loco's in the shops still have the old R8215 decoders in them. They are rubbish.

The new engines (HST's) are now fitted with the new R8249 decoders which are no problem, and as I have reported before, work with a Prodigy advance2 controller which the R8215's would not.

The R8215's are identified as follows: version 1 - no coloured spot on the chip. Version 2 - a yellow spot (or was it white?), Version 3 - a red spot.

The R8249 is identified by a Blue spot.

Hope this helps.

AlanB
 

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Hi
The new Hornby R8249 decoder is now NMRA compliant and is receiving some good reports from end users, especially those with more modern stock (lower motor current loadings).
It is of course a very basic budget decoder, but does offer four digit addressing and a few CV adjustment (not many though!) and a quite small size.
As correctly stated by alanb, unfortunately a lot of DCC fitted recently sold and some unsold stock still contains the older decoder which we all know had some problems. Shame really that Hornby aren't recalling all the unsold stock for replacements to the new decoder and remove in one swoop all their DCC fitted problems!

If any Hornby DCC fitted loco is poor performing, the owner can return it directly to Hornby Service Dept at Margate for a replacement under warranty, which I am lead to believe will be carried out using the new R8249 decoder. I have also read of a few users who have contacted Hornby and they have sent them free replacement new decoders for themselves to fit if they are of that inclination to do so.
 

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Discussion Starter · #6 ·
Thanks for the info on the new decoders but I think I'll stick with the tried and true TCS M1-UK and DP2x-UK decoders until I get all my locos converted over to sound. This will a monumental task as I'm over the 100 mark now. Trouble is they keep bringing them out and I cannot resist.

Charles Emerson
Queensland
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As the accepted wisdom is to remove the suppression capacitors before fitting a DCC chip why don't Hornby, Bachmann etc fit the suppresion components on the blanking plug. Then when the modeller removes the plug from a DCC Ready loco then they'll also remove all the offending components whih are known to cause problems? Or am I missing something oobvious here?

Keith.
 

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QUOTE (GoingUnderground @ 2 Jan 2009, 16:56) <{POST_SNAPBACK}>why don't Hornby, Bachmann etc fit the suppresion components on the blanking plug.
For the simple reason that for a supression component, such as a capacitor to be effective it simply has to be mounted as close to the source of interferance as possible i.e. the motor brushes.
 

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Also the manufacturer is responsible for supplying a product that meets the EU requirements on RF suppression. If they make the capacitor removeable then they are arguably also responsible for it meeting the same requirements with a decoder fitted. This is quite a tall order as they have no control over the decoder design or even any idea which one will be fitted.
 

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QUOTE (Brian Considine @ 2 Jan 2009, 17:57) <{POST_SNAPBACK}>For the simple reason that for a supression component, such as a capacitor to be effective it simply has to be mounted as close to the source of interferance as possible i.e. the motor brushes.
Forgot that they're supposed to be as close as possible to the source of the RF interference.

QUOTE (Edwin @ 2 Jan 2009, 18:22) <{POST_SNAPBACK}>Also the manufacturer is responsible for supplying a product that meets the EU requirements on RF suppression. If they make the capacitor removeable then they are arguably also responsible for it meeting the same requirements with a decoder fitted. This is quite a tall order as they have no control over the decoder design or even any idea which one will be fitted.
So as they have to be there for the loco to comply with Legislation then why are so many stories across railway modelling groups on the web that tell tales of decoders behaving badly with capacitors in situ and then turning into angels when the capacitors are removed. It does make me wonder exactly what are the parameters within which decoders are are designed to work.

Whinge over.

Keith.
 

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QUOTE So as they have to be there for the loco to comply with Legislation then why are so many stories across railway modelling groups on the web that tell tales of decoders behaving badly with capacitors in situ and then turning into angels when the capacitors are removed. It does make me wonder exactly what are the parameters within which decoders are are designed to work.

Without wanting to go over the same ground again, the short answer is the capacitors are there for the case where the motor is connected directly to the transmitting aerial - I mean rails. I understand that decoders can be designed to work with some capacitance present to a greater or lesser degree. Some manufacturers claim they have done this. Once a decoder is interposed between the motor connections and the aerial (rails), the RF transmission circuit has fundamentally changed, as has the drive signal so the original capacitors are almost certainly not fulfilling their original design purpose.

Why do DCC fitted models still have the caps fitted? Good question. The most likely answer is that the decoders are fitted after the standard motor and wirung harness and it's easier for production purposes (training or whatever) to leave that sequence alone and fit the caps. So long as the decoder can cope this is ok.....

David
 

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Hi!

I wanted to try the Hornby R8249 decoder in my HST rear (unpowered) unit. My reason for this was that a cheap decoder would do nicely since it didn't need to control a motor, just the lights. To my great surprise the yellow wire was not soldered to the decoder, just to the plug, rendering it useless for my purpose! My unit ended up with a Digitrax decoder and I will never buy another Hornby decoder again! Why is Hornby's quality control so poor?

Best Wishes,
Tom
 
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