Illuminating the NMT Pantograph Coach etc.

GlenEglise · June 30, 2025, 12:53:04 AM

I am modelling on a DCC layout and looking to replicate the various lighting effects on the Network Rail NMT set.

Has anyone done this previously for DCC Layout?

Can you advise the basic elements involved and appropriate supplier or other sources.

Have tried various methods so far none compatible with DCC.

Thanks in advance for any assistance or advice from those who have succeeded.

Kind regards,

GE

Steven B · June 30, 2025, 08:43:09 AM

What effects are you looking at replicating?

Dapol or Farish Mk3?

The Dapol Mk3 come with factory fitted electrical pick-ups and as easy to add lighting to. Both have space in the underframe for decoders and the necessary resistors.

njee20 · June 30, 2025, 09:13:20 AM

There used to be a supplier of a PCB on eBay for this purpose, but they seem to have stopped. LEDs with appropriate resistors, and a bridge rectifier to handle to unusual DCC waveform.

IIRC they've got 4 on the pantograph. Pretty sure they still work now there's no pantograph fitted, then you've got the scanning light on the same coach as a line covering the track bed.

ScottishModeller · June 30, 2025, 02:34:27 PM

Quote from: njee20 on June 30, 2025, 09:13:20 AMThere used to be a supplier of a PCB on eBay for this purpose, but they seem to have stopped.

Hi Nig,

The light modules from Illuminated Models are still available.

The problem appears to be that they are not suitable for use on DCC.

The modules themselves work fine on DC but getting them to work on DCC is proving to be a problem!

I think that's really what Brian is trying to work out. We have them in 4mm and they work on DC, but even using a function decoder cannot get them to work with DCC.

Phil H

njee20 · June 30, 2025, 05:44:55 PM

That's interesting. Can't get them to work as in they're not DCC-controllable or they don't work at all?

ScottishModeller · June 30, 2025, 07:20:52 PM

Quote from: njee20 on June 30, 2025, 05:44:55 PMThat's interesting. Can't get them to work as in they're not DCC-controllable or they don't work at all?

Hi Nig,

We can get them to work on DC.....

However, when tried to power on DCC - I get nothing at all.

My thoughts are that the output from the chip is too low.

I think the way the boards work means we need a constant 12v DC output from the chip.

Phil H

GlenEglise · June 30, 2025, 08:36:05 PM

Quote from: Steven B on June 30, 2025, 08:43:09 AMWhat effects are you looking at replicating?

Dapol or Farish Mk3?

The Dapol Mk3 come with factory fitted electrical pick-ups and as easy to add lighting to. Both have space in the underframe for decoders and the necessary resistors.

The coaches are Farish and the locos are Dapol

GE

njee20 · June 30, 2025, 08:47:30 PM

Instantly made harder with Farish coaches, as there are no pickups, so you'll have to install them somehow. Is switching to Dapol coaches an option?

Quote from: ScottishModeller on June 30, 2025, 07:20:52 PM
Quote from: njee20 on June 30, 2025, 05:44:55 PMThat's interesting. Can't get them to work as in they're not DCC-controllable or they don't work at all?

We can get them to work on DC.....

However, when tried to power on DCC - I get nothing at all.

My thoughts are that the output from the chip is too low.

I think the way the boards work means we need a constant 12v DC output from the chip.

Isn't that why you add a bridge rectifier? To convert the AC DCC signal to DC? Interesting though. They're the ones I was thinking of. I see they do the pantograph and the laser.

acook · June 30, 2025, 11:25:56 PM

Bridge rectifiers are designed for mains frequencies, 50/60 Hz (cycles per second for the aged and infirm)

DCC is 8/10 kHz so the diodes cannot react fast enough to rectify the current.
Need to use signal diodes as they react fast enough.

Alan

Steven B · July 01, 2025, 09:09:48 AM

If this is the NMT laser car module then I'd suggest removing the rectifier-diode package (D1 on the board), and connect the decoder's function outputs directly to the pads marked + and -.

What you might have a problem with the number of LEDs and the current they draw - they might need more than a single decoder output can provide.

Standard bridge rectifiers do work on DCC but may cause corruption of the DCC signal so using high speed rated signal diodes is recommended.

GlenEglise · July 06, 2025, 09:54:34 PM

I must admit that I am not particularly up to speed on electrical functions so find it difficult to follow what would be needed to make Illuminated Models iitems work on DCC if that is indeed the case.

They have already told me that they work but I would like some confirmation from someone who has used their product.

I feel that I am going round in circles with this quest.

Does anyone know if the existing items from Illuminated Models actually work on a basic DCC setup? Would a decoder or two be required?

GE