Fitting Decoders to the Bachmann class 66



I'd have thought the obvious thing to do was to make up a small batch of 200-500 or so and offer them for sale at one of the main exhibitions, such as Warley. They could also donate some to the appropriate layouts at the show on the condition that they run them so the public can see and hear how they operate.
--
Jane
OO in the garden http://www.yddraiggoch.demon.co.uk/railway/railway.html
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"Jane Sullivan" wrote

This would be an expensive way of marketing the thing. The sound chip would only be viable if produced by the multi-thousand.
John.
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South West Digital is working on its own sound chip for the UK66 and I don't expect to see any change out of 110.
(kim)
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"kim" wrote

don't
Me neither, and you won't until the Chinese get involved with their manufacture and start churning them out by the tens of thousand.
I suspect South West Digital turn their decoders out by the tens (or may hundreds) but until the price drops significantly that same price will stop very many enthusiasts from buying.
John.
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Chris wrote:

The DCC signal is rectified with a bridge rectifier to provide DC traction power. This is regulated to a lower voltage to power the microcontroller that generates the PWM signals based on the incoming commands. The motor drive is a MOSFET H bridge. I'd be confident to assert that this is true for at least 99% of all commercially available decoders.
What you describe sounds more like a DIY system once produced by Maplin, 20 years ago, and maybe Zero-1 but I don't know about that.
Andrew
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Only when fitted in series. When fitted in parallel - as in most models - it acts as an AC attenuator affecting higher frequencies more than lower ones. The exact reverse is true of RF chokes.
(kim)
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In case anyone with limited electrical knowledge is tempted to try this I should warn them that removing the inductors (or "RF chokes" as I prefer to call them) will also remove the power supply to the motor. The supply path has to be made good again by fitting new wires which is not always straightforward where printed circuit boards are involved.
(kim)
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I know I said that my last posting was my final say on this subject but Kim's comments has to be addressed. The whole point of removing the C's & L's is to isolate the motor when fitting a decoder. I would not suggest removing any RFI components if the loco was to be used on a DC system, they are there for a purpose! The power for the motor is fed, in total isolation, through the orange and grey wires from the decoder. As to the point of "anyone with limited knowledge etc" someone with limited knowledge should seek guidance on how to proceed before attempting to fit a decoder. Some models are easy to do whilst others can be an absolute 'pig'. One in particular comes to mind is the China made R369A BR 3 Car DMU 110. A ringfield motor is used on this model but on first glance one wonders how the power is fed to the motor as there is only one wire to one of the brushes. It turns out that the left hand, the one without any wires to it, brush is fed via the long self tapping screw picking up the right hand rail power through the body of the motor. To successfully isolate this brush the long screw must be discarded, the self tapping hole re-tapped to 6BA and a non conductive 6BA bolt - I used a nylon one - used to hold in place the brush spring cover. The orange wire can now be connected to the brush terminal. I will now get off my soap box and go and hide in the corner :-).
Chris
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"Chris" wrote
As to the point of

rail
the
:-).
Just a further comment on this, all of which is quite correct for that particular era of Hornby Ringfield powered units (locos or dmus) but it is no longer the case with current (Chinese) production models in which both brushes are now electrically isolated from the motor chassis and pick-ups.
Consequently the process identified by Chris is no longer required on *current* models.
John.
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