frechett@boulder.Colorado.EDU (-=Runaway Daemon=-) (09/17/90)
Recently a friend of mine got infatuated with my 48 and so he went and bought one. It has worked fine for 4 days. Last night he was playing with it and it started screaming. I don't mean that it freaked out mathimatically. I mean that it actually started screaming. VERY very high pitched whine is heard continuously when the calculator is on. Thinking that something was wrong, he did a reset ON-A-F and it continued to whine. That is when he showed it to me and I caompared it to mine and indead my calc does not whine. I then did a push-button reset and it is still whining. Everything still works ok but the noise is a bit of a pain. He plans to take the calculator back but i would like to know if this has happened to anyone else with a Rev-D rom. Any ideas on what it might be would be informative.... Also since he is returning it and I have just heard that Rev-E is out my friend would like to see if he could get Rev-E instead of another D. My question is, is Educalc actually shipping E roms yet? ian -- -=Runaway Daemon=-
frechett@boulder.Colorado.EDU (-=Runaway Daemon=-) (09/17/90)
I had to follow up on my own article because I found a couple things. I found that my friend's calculator whines when it is on but if you enter the commmand line then it goes to alternating whine-hiss-whine-hiss.... When any key is actually depressed it will produce a steady hiss, and the most fun was when I got it to go whiiiiiiine-hiss-whiiiiiiiiiine-hiss.... and I realized that it was the clock. Everytime the second hand changed it would produce a short hiss. Basically, it would appear that any change will produce a noise. This is ANY change. I tryed tetris, and it produced the most amazing whines, clicks, pops, and shreaks. In my last post I said that mine didn't do this. I was wrong... after listening to my machine in better conditions, I determined that it does indead make noise but that it an order of magnitude lower in volume. I am willing to bet now that most people's calculators do this. What I want to know is why, and why is this one particular machine so damn loud. I find it fascinating and a bit disturbing. ian -- -=Runaway Daemon=-
jco@reef.cis.ufl.edu (Dumpmaster John) (09/17/90)
I bet if you hold yours up to your ear you can hear yours making that noise
too. It's the DC to DC converter in there to make the 15 volts they need
for the LCD (at least I think thats what it is.) you can change the pitch
by changing the contrast. (Make the DC-DC converter make different
voltages.)
Anyway, that would be my guess.
later
jco
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