Robert Kubichek wrote:
Topaz305RK wrote:
Need a little info please.

Have a Yaesu FT-990, no service manual. The light on the meter is dead.
Anyone ever change out one of these bulbs?
Is it a major undertaking or just minor surgery? Have changed a couple
of
"grain of wheat" bulbs in dual band mobile radios before.
Just thought I would ask before tearing into the thing. If it is a real
major operation will send it off, other wise will dig in and do it
myself.
Also, if someone has the service manual, perhaps you can pass along the
part
number for the bulb, assuming it is a bulb and not a back lit meter of
some
sort.

Sam - K7SAM



It is a 12v lamp according to schematic,and you would be much better off
replacing it with a led and resistor...


Bob N9LVU

LEDs tend to have a very narrow dispersion angle. A friend (service
'mangler' for a pro-sound company) gave me a tip: file-off the lens of the
LED.
If you want to stay with grain-of-wheat bulbs, and can't get the OEM units,
you can find them at well-stocked hobby stores. To make them last longer,
you can use a constant-current source (LM317L, etc) to limit the in-rush
current. You'll lose 1.21V across the '317, which may still be acceptable.
73,
Bryan WA7PRC