Thread: S-Meter repair?
View Single Post
  #12   Report Post  
Old June 14th 07, 07:43 AM posted to rec.radio.amateur.boatanchors
Bryan Bryan is offline
external usenet poster
 
First recorded activity by RadioBanter: Jul 2006
Posts: 199
Default S-Meter repair?

W9GB wrote:
KR6LP - Lake Perris QRP Society
Another approach using Paint Shop Pro
http://www.qsl.net/kr6lp/meter.html

Backlighting with an LED (S-meter)
http://www.pan-tex.net/usr/r/receivers/elrsmeter.htm

I find LED backlighting an interesting topic in itself. When attempting to
replace the burned-out grain-of-wheat lamps in my Kenwood TS-120S with LEDs,
I found the dispersion angle such that it didn't illuminate the entire
scale -- only a spot in the middle. A friend (service manager for a local
pro sound dealer) then mentioned, "just grind or file the lens on the LED,
and the dispersion angle will increase a lot". The next time I need to
replace lamps, I'll do that.

Also in regard to LED backlighting, I learned that not all white LEDs are
created equal. Most emit a bluish-white light, and are rather pricey
compared to other colors (even compared to blue LEDs). Just this week, in
refitting a ring light for a microscope with white LEDs where I work, I
found a pretty good lamp that's handled by Mouser (http://www.mouser.com/).
It's called a "warm white" LED, T1¾ package, and is only $1.00/ea. Search
for stock #889-LM560.

Vy 73,
Bryan WA7PRC