:: Plus, the LED is backwards (I think).

On the PCB are four soldered terminals labeled A and K coming from the 
LCD itself.  The 'A' terminal is connected directly to the 
collector/drain of Q3 the 'K' terminal connects directly to Vdd. I've 
assumed that the abbreviations are for anode and cathode.

However, (I'm spicing it as I type), if the PNP collector is at a 
lower potential (even if positive) than the 5v supply, then I think 
the LED(s) are the right way around. Q3 is turned off to switch the 
backlight on.

Perhaps the designer is from the 60's and likes PNP BJT's much like my 
first transistor radio all OC44's and 81's.

Colin
--
cdb, colin@btech-online.co.uk on 12/08/2009
 
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