In article , Rick Hughes
writes
On 03/02/2014 23:39, fred wrote:

Note that if you go for 20mA then you will limit your pulse resistor
size to about a quarter of the sizes I suggested (power = I sqrd x R),
you will be limited to 1k or so make sure you test for durability of
your non spec'd leds at those pulse levels before building in quantity.

OK went and ordered some 0.22uF X2 caps ... so when they arrive will
try them out ... so with the aim to be at 20mA, am I following you
correctly to use 1k 1/4 resistors ?


Actually no, the values I recommended are those given in my second post
in this thread[1] but you have chosen to ignore them.

My mention of 1k was a warning that that was the maximum value you could
use at your new current level without the resistor bursting into flames,
it was not a recommendation to use that value.

If you insist on using those values then you do so at your own risk but
in the interests of safety for you and yours, I will point you at:

http://cpc.farnell.com/RE06270 1k0 0.5W carbon comp 350V working, 700V
permitted overload

1/4W is not suitable, nor is anything other than a pulse capable, high
voltage resistor.


[1] In my earlier post I suggested a 4k7 0.5W 350V Carbon composition
resistor for use in a 7.5mA circuit but incorrectly gave the part number
for a 680R resistor. The correct part number for 4k7 is:

http://cpc.farnell.com/RE06278
--
fred
it's a ba-na-na . . . .