Steam Loco Modern Headlamp Help

[daz9284]

Hi all, sorey if this is in the wrong section of the forum.

 

Does anyone know where I can get, or get someone to make, a single headlamp with LED, to repalce the black non working headlamp in the pic below. It is for my Hornby tts sound fitted A4 . Including the necessry resitors and wire etc to wire it to the decoder / or 8 pin plug?

 

Many thanks

Darryl

Edited September 18, 2019 by daz9284
Title and content edit

[Phil S]

The 'diy' solution would be to use a 1mm (approx) modelling drill it in a hand held pin vice ....probably after cutting off the 'blip', and then making a starter hole to help locate the drill bit.

Then a pre-wired SMD LED glued to the rear ....inside the body shell.   If you had any fibre optic strand, you could feed it through the hole ( and the fibre size would dictate the minimum hole size ) before fitting the smd led behind it.....otherwise A single drop of liquid glaze or poly cement

Readily available sizes of prewired smd  can be found on eBay and also from eg Digikeijs and DCC concepts.

Buying pre-wired is much easier than trying to solder your own .... Especially with the smaller sizes. ( which I use for 'door unlocked/open lights but then I put the smd led on the outside, and pass the wires through the hole )

They are available 'with' or 'without' resistors .....sometimes the resistors are separate in the pack ( otherwise the wires could not be passed through fine holes... As needed when I use them as rectangular door lights)

 

YOU will then still have to make the connection at the 8 pin socket to the holes/pins used by the green (-ve ) and blue (+ve) 

Connections .... Nothing premade is available for such a specific task that I am aware of.

If you are unwilling to solder ...then ask via your local model shop if whoever they use for decoder fitting would do the job.

Otherwise, premade 'lamps' in 00 are available .. Search DCC concepts site?

Edited September 18, 2019 by Phil S
Resistors

[newbryford]

I've fitted modern style battery lamps to a couple of my steam locos.

I used a dummy Dapol tail lamp - that they supplied with each HIA hopper.

Hollowed it out at the back and drilled a hole, then fitted a white nano LED.

Filled the back with epoxy resin and filed back to shape.

Connected as Phil says above

 

(I'll see if I can find a photo)

 

(WCRC have both black and white painted battery headlamps - they use whichever is given to the driver from the stores!)

 

DCC Concepts don't make a modern style white headlamp.

 

Cheers,

Mick

Edited September 20, 2019 by newbryford

[daz9284]

many thanks for the reply guys. I already have a flickering 'firebox' wired to the green pin. I don't want the headlight to be directional and i want it to be controlled independantly to the fire box so would it be a case of wiring it to either of the white or yellow pins?

 

many thanks

Darryl

[newbryford]

White or yellow is good.

The default for white or yellow  outputs will be directional anyway.

Quite a few decoders have the ability to make any output directional or other feature, such as strobe or flicker. - and then re-map to other function keys if required.

What decoder is it?

 

Cheers,m

Mick.

 

 

[daz9284]

9 hours ago, newbryford said:

White or yellow is good.

The default for white or yellow  outputs will be directional anyway.

Quite a few decoders have the ability to make any output directional or other feature, such as strobe or flicker. - and then re-map to other function keys if required.

What decoder is it?

 

Cheers,m

Mick.

 

 

cheers mick

 

It is the Hornby TTS sound decoder.

 

regards

Darryl

[pauliebanger]

Darryl,

 

Join the white and yellow wires together to allow the LED to operate in either direction

 

Remember that LEDs will require a current limiting resistor in series to protect them from over-current.

 

Best regards,

 

Paul

[298]

On 27/09/2019 at 10:37, pauliebanger said:

Darryl,

 

Join the white and yellow wires together to allow the LED to operate in either direction

 

Remember that LEDs will require a current limiting resistor in series to protect them from over-current.

 

Best regards,

 

Paul

 

Probably not a good idea without a diode in each wire as some decoders don't like voltage into the function output. I accidentally did it recently and the decoders protection shut the function outputs down, but it took a while to diagnose the fault.

[Phil S]

Having just written a wiring-suggestion below - I decided to ask a new question first ....

IF your TTS decoder is located in the TENDER - along with the speaker - then a cheap, 2nd, silent decoder may be your easiest and most optimum solution - avoiding extra wires between loco and tender, and therefore allowing the loco and tender to be separated during servicing etc.

 

A 2nd decoder will give you more freedom to choose a suitable F number  (not that Hornby have left many unused !) ... you could even use a differnt loco addess !  ( and a function decoder .... but loco decoders tend to be more economical and available)

 

However - you may have made use of the space within the Mallard Bodyshell for the speaker+decoder.

 

So, with the Green wire already in use,  the white wire allocated to your other forward lamps ??? - and directional FORWARD on ...   the normal  suggestion is  2 diodes and 1 resistor  

( 1N4148 are small and cheap and adequae, but any small diode will do )

 

Wiring Path:

Blue Positive (also going to your Firebox light.....)  to a 1k-2k resistor*  [AOT]

From Resistor to Modern Lamp LED+ve --- follow maker's guidance on which colour wire is +ve/-ve) 

From -ve side of LED to BOTH diodes ( end without band )

From  each diode ( end with band ) to either the White  or Yellow wires  (these are pulled to local 0V when the Function is 'on')

*AOT Adjust on Test - brightness preferred will depend on your ambient lighting level and how efficent the LED used by the 'Modern Lamp' maker is ....new LED designs are much brighter than older types.

 

[pauliebanger]

4 hours ago, 298 said:

 

Probably not a good idea without a diode in each wire as some decoders don't like voltage into the function output. I accidentally did it recently and the decoders protection shut the function outputs down, but it took a while to diagnose the fault.

 

Don't see a problem and it's something I've done many times.

 

The Function Outputs on TTS decoders are Open Collector (A.K.A. 'Normal' or 'Full Power'). They expect to have a voltage fed into them as otherwise they don't work.

 

There's only one LED which would be fed by Blue (common Positive) and the return either via White (FOf) or Yellow (FOr)

 

Logic Level Function Outputs would be different.

 

Best regards,

 

Paul

[daz9284]

thanks for the replies guys.

 

there will only be one lamp working (the middle one) so because don't want the light to be directional, shall i connect it to both the white and yellow wires on the decoder, or to just one and remap the cv so the light stays on all the time with the function pressed?

 

regards

darryl

[Phil S]

With open collector and pull-down for active, then there should be no problem leaving them as supplied ie directional ...  (It wouldn't matter, either, if both ended up on at the same time ... simply half the current would pass through each switch ... not affecting the  total current load of motor, sound and Lighting.)

 

 

[RAF96]

You can’t remap TTS decoder functions and F0 directional lights are an on/off toggle so they are default off, but once selected they stay on until you switch them off again.

Edited October 12, 2019 by RAF96
More info added

[pauliebanger]

3 hours ago, daz9284 said:

thanks for the replies guys.

 

there will only be one lamp working (the middle one) so because don't want the light to be directional, shall i connect it to both the white and yellow wires on the decoder, or to just one and remap the cv so the light stays on all the time with the function pressed?

 

regards

darryl

 

Darrl,

 

I gave you the correct wiring advice earlier in this thread, based upon the fact that I could see that this was a TTS decoder and therefore not remappable. That's why I suggested physically dualing the return and not simply remapping, (which is what you would do with a more fully featured decoder).

 

Whether the function is momentary or latched will be a feature of your controller.

 

Because of the limited support for CVs in TTS decoder software, if you want the lamp to illuminated in forward and reverse  you have no choice as to how it can be done*. Connect yellow and white wires together. This forms a return to open collector via white (FOf) when moving forwards and yellow (FOr) when moving backwards. The blue wire is the common (positive).

 

 *Strictly, you could use the green wire instead but then you would have to use the Hornby assigned F key to operate the lights insteadof most common F Key 0.

 

You must have series resistor(s) in place to protect the LED from over-current. These may already be built in to the LED or into the lighting PCB if there is one. If you are connecting essentially direct to the decoder you will need to add a resitor or your LED will flash and die.

 

Best regards,

 

Paul

[daz9284]

many thanks again for the replies, i will get round to wiring it up at some point between working and sorting for a house move.

 

Paul, don't want to use the green wire as i already have a flickering orange firebox led fitted to the green wire.

 

many thanks

Darryl

[pauliebanger]

11 hours ago, daz9284 said:

Paul, don't want to use the green wire as i already have a flickering orange firebox led fitted to the green wire.

 

Darryl,

 

Yes, I read that in your earlier response, but I mentioned it for completeness and a) to avoid being 'corrected' and b) for the sake of other readers for whom that option would be viable.

 

Good luck with the house move.

 

Best regards,

 

Paul

 

 

[Phil S]

what is causing the 'flickering' on the green wire ?   ... if it is the firebox led assembly /module -  then there is no reason the front light could not be on the same connector ... in parallel; each with their own resistance, and total (well under) the 100mA limit of all functions.

[daz9284]

17 hours ago, pauliebanger said:

 

Darryl,

 

Yes, I read that in your earlier response, but I mentioned it for completeness and a) to avoid being 'corrected' and b) for the sake of other readers for whom that option would be viable.

 

Good luck with the house move.

 

Best regards,

 

Paul

 

 

cheers mate. moving from working for TPE at York to working for DB at Mossend :-)

[daz9284]

17 hours ago, Phil S said:

what is causing the 'flickering' on the green wire ?   ... if it is the firebox led assembly /module -  then there is no reason the front light could not be on the same connector ... in parallel; each with their own resistance, and total (well under) the 100mA limit of all functions.

yes it is the firebox module. I don't want the front light to come on at same time as the firebox.

 

I guess if I want to fit a smoke generator then I would have to change the sound decoder so I have more aux functions?

 

regards

Darryl

[Phil S]

Your cheapest option is probably to keep the TTS decoder for the Sound and Motor,

and simply use a Lenz Std V2 or similar decoder for the functions ... 'easily' redefined to other function numbers  - BUT  be aware that using a function number which on the TTS decoder operates a sound  would 'use up' one of your 2 sound channels even though you set its volume to zero ( I assume - not tested) ....so that would imply using unused high numbers OR duplicating the Lighting function allocations - as these do not use sound channels on the TTS.

The lenz may even be able to provide the 'flicker' for the firebox without any additional circuitry (other than led and resistor)

[Other decoder makes are available and may be easier or more familiar to you [but not to me 8-) ] for redefining function outputs.  It is less economical to use a function-only decoder becasue the market for them is less, therefore they tend to be more expensive per output.  Some decoders allow the motor outputs to be used as binary on/off ??? or this can be emulated by defining the speed profile (but off at zero speed)]

'Smoke' might even be allocatable by using it on the 2nd decoder's motor outputs.... which then suggests 'consisting' as a way of operating 2 independent decoders together as needed.