[Heathkit] LED backlight mod on SB200/220 meters

[Johnnie Walker]

David,

Thanks for the comments. 

The hole clearly is big enough to stick a led into,
the problem is the 
led tends to be far more directional than a bulb.  So
the closer the led 
gets to the back of the meter, the more ununiform the
lighting gets.

I have seen some tiny LCD backlights that are LED
driven so that the LED 
is focused along the length of the small plastic that
serves as a 
diffusior.  The trouble is that, now when I want to
locate and buy one, 
I can't find anything like that either...

Another option i have thought of is to mount a few
LEDs on a strip of 
some kind.  And then orient them so they point to the
meter on the front 
side.  The stip would need to be encased in something
asthetically 
pleasing or it would lousy.  But the diffused backside
lighting is 
really the effect I'm hoping to find a solution to.

73/jeff/ac0c

David Goncalves wrote:
> One could crunch out the guts of a bulb, solder in
the LEDs and use
> devcon 2-ton epoxy and a form to build an LED
'lightbulb'.
>
> On Fri, Jan 9, 2009 at 10:33 PM, Johnnie Walker
> <keepwalking188 at yahoo.com> wrote:
>   
>> Gentlemen,
>>
>> I am wondering if anyone has found a clean solution
to
>> providing a
>> replacement for the incandescent bulb backlight on
the
>> old Heath amps?
>>
>> I have removed the bulb and suspeneded a few leds
>> about an inch or so
>> behind the meter so that they provide a diffused
>> backlight.  While the
>> look from the outside of the case is fine, it's not
a
>> very elegant solution.
>>
>> Appreciate comments from anyone with experience or
>> suggestions.
>>
>> 73/jeff/ac0c
>>
>>
>>
>>
>>
>>
>>     
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