On Fri, 05 Nov 2004 09:00:55 -0600, John Fields wrote:
On Fri, 05 Nov 2004 03:38:03 GMT, "James Sweet"
"BOB URZ" wrote in message
John Fields wrote:
On Tue, 02 Nov 2004 19:33:59 -0600, BOB URZ
wrote:
I am looking for a good cheap source for generic EL panels for
some older equipment retrofit. Has anyone done EL panel replacement?
Can
you just cut them down without damaging them?
How critical is the voltage range to drive them?
1. Good and cheap are sometimes mutually exclusive. How much do you
want to spend, say, per square inch?
2. I have.
3. Usually.
4. Not very. 90 to about 120VRMS will usually work OK. You can change
the brightness by varying the voltage and the color (somewhat) by
changing the frequency. Life to half-brightness varies inversely
with brightness and with frequency.
Ok, the retrofit application i have has a display about 3/4" wide by
4" long. Plastic encased like a laminated card. The EL display
backlite is dead. Measuring the voltage with my fluke on AC scale measures
about 55 volts AC. Is this too low for operation? It seems to be powered
by a
sealed step up module

Bob


What're you measuring it with? The high frequency AC won't read correctly on
most multimeters, even some true RMS ones can't go that high. Try using an
oscilloscope if you have access to one.

---
The truth is, it makes very little difference. The goal is to get the
thing to light up, not to determine, to the Nth degree, what's driving
it, so pretty much whatever the waveshape is is fine if it works.

But the problem was, it wasn't lighting up at all. A failed power supply
could do that, couldn't it? 55V is noticeably less than 90V, albeit that
_could_ be attributable to the meter, of course.

I'm "only" a tech, but one aspect of troubleshooting is determining
exactly where the failure has taken place, and diagnosis can be
cheaper than shotgunning, especially if you have to make up a
custom part.

Thanks,
Rich