Backlight tip and RAM question

eh? ((no email))
Sun, 01 Aug 1993 03:45:58 HST

First- *** thankyou Brian for your timely and relevant responses ***
This listserver is _great_

I'll begin with my "tip":

The backlight on my (used) UL was inoperable (in fact, the original
inverter had been removed, but the backlight panel remained). I bought a
surplus inverter (+/-15vdc to 160vac) from ALL ELECTRONICS for about $5, and
stripped off part of the plastic casing from the inverter (it was encapsulated
in epoxy, inside a thin plastic box) in order to make it nestle properly in
the inverter compartment inside the UL case (just above the main power
supply).

Unfortunately, I rushed trying it out with the backlight, by
immediately hooking it up to a (purple?) wire that appeared to be carrying
about 19vdc from the power supply (this wire was hanging loose, and I assumed
it had originally been connected to the original inverter). The backlight
leapt to life, then went out as one of the diodes (or something) expired on
the power board... think I overdrove it.

Anyway- in the end I wired the new inverter directly to the 12vdc
at the connector coming in from my kludge power cube. That worked well,
although the display is not quite bright enough to use in full daylight.

Tonight I've been playing around with an adjustable bench supply, and
find that if I put about 18vdc into the power connector, I get an admirable
amount of backlighting, although the power board is generating a bit of heat,
with the regulator sluffing off that extra 6v... my new plan is to get a
surplus 18vdc power cube, install a mini-phono jack on the PCMCIA cover for
power input, wire that directly to the inverter, and use four or five diodes
(0.7v drop each) between there and the power board to drop the power supply
voltage down to a safer level. Makes sense to me- cheap and dirty.

As an aside- the backlight/inverter are drawing about 150ma with 13vdc
input- that runs up to around 250ma when I kick the input up to 18vdc.

So- now for my question: I find myself with a 1mb "silicon disk". Looking at
the card, it appears the same board would be used for the 2mb configuration,
but with an extra 8 memory chips and a few caps. It would appear that, if I
were able to buy the extra chips (or get hold of another 1mb board and remove
the chips on that)... well, you get the idea. The soldering job doesn't look
that difficult, but the chips are unfamiliar- they are marked

NEC D42601LA-60A 8912EU007

and are 20 pins semi-surface mount (pins bent under body of chip). Does anyone
know of a source for these? Or have an old 1mb board lying around? It would
probably be safer and cheaper to buy one of the JEM 2mb boards at $50, but I
thought it would be worth asking...

thanks in advance for any advice-

aloha.