Hello Gerson,
If only a part of each segment does not light, then you should test the display.
Here's what I usually do (Luiz might have a better idea):
1) Take the display out if unsoldered otherwise use your probes.
2) With an ohmeter, check continuity of each display circuit track from pin to end of visible track. If a track is broken, tin it with your iron.
3) With your bench PSU at 1,5V DC (+current limit to 20mA if you can), apply BRIEFLY voltage directly to couples of the display pins.
Powering anode & cathode should (and I hope will) light the corresponding segment for each couple.
Continue till you find an offending segment.
If all segments light this way, then the problem is NOT with the display.
4) If problem is not with the display, repost here for us to go further.
5) If problem is with the display, let's wait for somebody else's idea because I've tried everything including ultrasonic cleaning with no result.
6) If nobody has a better idea, check your mail once again :-)
Best regards from France!
Etienne
PS: Well, I'm getting snobish with my "PSU", a simple 1,5V battery will do ;-)
Edited: 5 Nov 2005, 12:49 p.m.