08-06-2019, 02:39 PM (This post was last modified: 08-06-2019, 03:03 PM by Vipersan.)

Acting on Jims advice ..the LEDs were removed and I decided to tackle the problem this way (see photo)
I have fitted a 470 ohm resistor ..and hopefully Jim will provide the other values so I can complete it.
I then have to run 3 pairs of wires out to the compaqt front panel and mount 3 x coloured LEDs..
rgds
VS

08-07-2019, 12:38 AM (This post was last modified: 08-07-2019, 01:07 AM by Vipersan.)

Thanks Jim ..I'll get on that later today when I am fully awake.
rgds
VS
110 ohm is going to be a tricky value for me ..
How critical I wonder ? ..I have 100 ohm and 120 ohm ..
So most likely I will have to use 100 ohm ..and drop a 10 ohm in the actual lead to the blue LED .
but I guess this is an option.

08-07-2019, 09:45 AM (This post was last modified: 08-07-2019, 03:38 PM by Vipersan.)

Sadly this box of 3mm water clear leds didn't come with forward voltage ratings ...so I could just use the "typical" ratings ...or try and set up a breadboard to ascertain them ..
Typical for R G B would be 1.8v , 2.2v and 2.8v ...
but how accurate this is I have no idea ?
would you recommend an exact calculation Jim ..or do you think this would be 'close enough'
rgds
VS
..so doing the calculations and assuming the typical forward voltages for this type of 3mm coloured led
..gives me :-
Red - 300 ohm
green - 220 ohm
blue - 100 ohm

blue being the closest to the original resistance
but short of knowing for sure what the forward voltages of these leds are...pure guesswork.
They are all close-ish ..but left as is theoretically they would glow similarly or a bit dimmer passing less current in the case of red and green that is.

08-08-2019, 12:29 AM (This post was last modified: 08-08-2019, 01:25 AM by Vipersan.)

Dimmer but safer sounds good to me Jim ..
I think I'll chance leaving the resistors at the value set by you ..plus put an extra 50 ohm in series with the +ve leg of each front panel substitute LEDs.
rgds
VS

I would recommend 330 ohm for the red and 100 ohm for the green and blue. That is a really high forward voltage for the green LED. Normally, those are around 2.2v.