Skarloey question

[Jeff Schumaker]

Esteemed group,

Can someone tell me what the tiny circuit board with the electronic bits is for that's wired to Skaloey's motor? I have been told that it's the constant lighting circuit, but as there are no lights on Skarloey, I question that.

Jeff S.

[Mark Shenstone]

My guess is that'd be the factory fitted DCC chip as the vast majority of Barchmann USA locos now have them fitted as standard. Does the box make any mention of DCC? If you have the box that is :)

[Jeff Schumaker]

My guess is that'd be the factory fitted DCC chip as the vast majority of Barchmann USA locos now have them fitted as standard. Does the box make any mention of DCC? If you have the box that is :)

No mention of DCC on the box.

Jeff S.

[JulienW]

I've had a look at the paperwork that came with mine (but admit I haven't taken it to bits - yet!).

Could it be the modern equivalent of the old TV supressor capacitor wired across the motor terminals?

[Graeme Dunbar]

Do you have a photo?

I have a Skarloey, but it is out of reach at the movement as we have the builders in and are effectively living out of suitcases.

[B.Meldon]

It is for radio and TV interference suppression.

One side has two surface mounted capacitors and a bi-directional diode. These are to stop sparking.



The other side has two wire coils wound around carbon cores, these stop any RF caused by sparking from going down to the track that would then act as an antenna.



Corrections to the above are most welcome!

Brian Meldon

[Graeme Dunbar]

Thanks Brian. Yes it definitely looks like suppression circuitry.

I would guess the carbon-like material in the coils/inductors/chokes is ferrite.

The bidirectional diode could be a transient voltage suppression (TVS) diode to short out any high voltage spikes and hence sparks generated by the motor.

[Jeff Schumaker]

Thanks for the information. I had thought that the circuit was for interference suppression, but wasn't sure.

Jeff S.

[B.Meldon]

Thanks Brian. Yes it definitely looks like suppression circuitry.

I would guess the carbon-like material in the coils/inductors/chokes is ferrite.

The bidirectional diode could be a transient voltage suppression (TVS) diode to short out any high voltage spikes and hence sparks generated by the motor.

Yes Graham that sound correct to me.

Brian Meldon