I think I'd be wary of using it as a PA amp. I mean on paper it will be fine but it is surprising how much spl a room full of people soaks up. Your asking it to work hard continuously for several hours...I wouldn't take the chance.
Current Lash Up:
TEAC VRDS 701T > Sony TAE1000ESD > Krell KSA50S > JM Labs Focal Electra 926.
Location: Chelmsford, UK
Posts: 34
I'm Ronald.
Although this is now a very old thread my NEC A820E is still going strong and giving a brilliant performance, just as it did the day it was new. (I have had this since I purchased it new.) I had the usual problem with mine that one or more of the indicator bulbs burn out with age. (They have now lasted more or less 40 years which is not bad.) However when I came to examine this my observation is that the bulb voltage of the originals is 4.5V not 12V. It is usually the two Active drive illumination bulbs which go first. As these bulbs are in series with the function switch bulbs none of them then illuminate. I made the mistake originally of thinking that these original bulbs were 6V; that was no doubt because I measured the available voltage supply when it had no load. I now believe and have observed that the proper voltage for these seems to be 4.5V. I did actually replace one of mine with a 6V bulb and that did work, but of course it does not glow quite as brightly as the other original 4.5V ones. That does not really matter with only one, since this will mean that the remaining bulbs will be under-driven, which should help them last a bit longer.
The circuit diagram and manual does not seem to indicate the correct voltage of these bulbs so this has to be determined by measurement. I note for anyone who may be interested that there is a guy selling these suitable 4.5V miniature bulbs on ebay. Do not forget to put the green translucent plastic sleeve over the new bulb to give a green hue to the display. If you cannot get 4.5V replacements then 5V will probably be near enough.