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Discussion Starter · #1 ·
This is my first attempt at DCC Loco conversion, hope this is of interest.

After reading many related threads on the forum, I decided to try out the TCS T1 decoder for the following reasons. It is good value for money, is a reasonably compact package, has good spec and is well recommended.
Converting this Loco was very enjoyable, the Bachmann PCB is discarded and it's metal mounting posts need to be sawn or cut off, then filed flat. Although hidden by the outer shell, I decided to paint this new surface black to keep things tidy. The TCS decoder is a perfect fit, I secured it with two sticky pads.

I havn't decided if I will fit lights to this model yet, but I wanted to test the forward & reverse lighting function as this is the first loco I've converted. Hence the basic test LED arrangement seen in the photo. For the time being, I've resisted the temptation to trim any of the wires just incase.

The problem is........my DCC system is yet to arrive, so I can't try it! With a bit of luck, all will be well.
 

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Discussion Starter · #4 ·
I tried the body fit before rigging up the LED's and it fitted OK, not much room for anything else though.

M1 & MC2 both look a good choice for small spaces, cost is up slightly however.
 

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Hi there Howzatt , looks like you have done a good job there ! Can i ask you one silly question ? I have fitted leds to a couple of my locos for directional lighting , but the leds had been taken from other trains with the resistors attached , so when i wanted to do more , i waddled down to my local maplin electronics shop and asked for some resistors ! When they asked which ones i told them the colour of the bands on mine and they could only find some in a pack of 500 (all different ones) . What should i be asking for ? Please help !
Keep up the good work , and after you have done your 50th dcc conversion you can do it with your eyes closed
!
Regards simon
 

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Discussion Starter · #6 ·

Simon, Thanks for your interest and kind words. Resistor values quoted by various sources seem quite conflicting. I have read that 1K ohm 0.25Watt resistors are a good value to start with, and I've fitted these as a starting point prior to testing. There is a good PDF guide titled "Simply Programming" for download from TCS (Train Control Systems) TCSDCC.com. This includes a table for resistor selection with both bulbs and LED's.
Probably best to get a selection of resistors to try until you acheive a desired brightness. e.g. 1K Ohm, 680 Ohm, 470 Ohm. Try Rapid Electronics, they sell packs of 100 same value resistors reasonably priced. Rapid Electronics.
After my 50th DCC conversion, I'll probably be a nervous wreck! My next project is a Bachmann GWR 57xx split chassis, and that to put it mildly, looks like fun.
 

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>Resistor values quoted by various sources seem quite conflicting
The resistor value depends on the voltage level of the output driving the LED and the current required by the LED to provide its rated output. As you may remember from your physics lessons, Ohm's law is V = IR where V is volts, I is current and R is ohms.

You get the volts value from the output of your decoder and the I from the data sheet on your chosen LED. Remember that the I in the formula is for Amps. LEDs take milliamps so remember to enter 10ma as 0.010 in your calculation. Since you now have V and I, you can calculate R as V/I;

For the power rating (watts), use P = IV where P is the power in watts. V and I are the volts and amps as before.

So for every combination of LED (I rating) and decoder output (volts) you will get different results for resistor value.

I hope this helps (and that I got it right!)

David
 
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