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HP Forum Archive 14

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HP-41: The Ultimate Alarm Clock
Message #1 Posted by Geir Isene on 20 Feb 2005, 7:14 a.m.

Having a HP-41CX (or HP-41C/CV w/time module) can make your nights and mornings better - with The Ultimate Alarm Clock.

It has a bundle of features, including one-button setting of an alarm, snooze, alarm hold and restart and much more. It can give you the current time by beeps :) It will even tell you how much longer before the alarm goes off, again by beeps.

Check it out at

Re: HP-41: The Ultimate Alarm Clock
Message #2 Posted by Vassilis Prevelakis on 21 Feb 2005, 12:41 a.m.,
in response to message #1 by Geir Isene


I had an alarm clock at school (a Casio CQ-1)that I liked a lot because I could set up the time quickly (via the keypad) as opposed to most alarm clocks where you have to waste time scrolling through the minutes and hours.

Anyway my poor CQ-1 bit the dust and I turned to my HP-41C (with time module) to wake me up. I created a program that would get my schedule from a file in Ext Mem and make sure I'd wake up at the right time each day (so I could set it up to wake me up at 8 am on Mondays, 10 am on Tuesdays, not to ring at all during weekends etc).

It would support snooze: if you pressed any key other than a specific key combination, it would sleep for 10 minutes and start ringing again.

I used the "phazer fire", a synthetic series of tones from a star-trek game as the alarm ring.

Unfortunately, the 41's volume is not loud enough to wake me up reliably and eventually I switched to a more conventional alarm clock.


Re: HP-41: The Ultimate Alarm Clock/Hardware BOOST?
Message #3 Posted by Veli-Pekka Nousiainen on 21 Feb 2005, 7:00 a.m.,
in response to message #2 by Vassilis Prevelakis

Maybe you just got used to the same melody?
randomizing different melodies might help.

Is there anyone here to know how to boost the sound?

Re: HP-41: The Ultimate Alarm Clock/Hardware BOOST?
Message #4 Posted by Les Bell [Sydney] on 21 Feb 2005, 5:31 p.m.,
in response to message #3 by Veli-Pekka Nousiainen

You could probably place the 41 at the focus of a roughly-parabolic "cone" made of stiff card; that would probably be enough to increase the sound level somewhat.

I still occasionally use my 41CX as an alarm clock, since the one in my wrist-watch isn't loud enough to wake me. And a few weeks ago, I was prescribed two different antibiotics to treat a tummy bug - one to be taken on a six hour schedule, one on an eight-hour schedule. I toyed with the idea of writing a program to remind me, or using one of the programs from the Timer Module Solutions Book, but in the end, I just "winged it", since it was only for a few days.


--- Les Bell

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