Larry's Blog

CREATING BELL SOUNDS

Just yesterday I determined to find a way of producingelectronic bell sounds.
There are some challenges here. A bell sound is a damped oscillation, that is, the frequency remains the same but the amplitude diminishes to zero. Also, can I use simple square wave for frequency or do I have to produce a sine wave?
There is also the question of attack. I believe this is the high amplitude of the beginning of the bell sound.

What I invision are some very loud speakers and effectivey an electronic carillon system. Other challenges will be to set up one or more of my PIC microcontrollers to generate the original frequencies for different tones, and signals to drive relays that will turn power on and off in parts of the circuit to achieve the decay. I will be working with a range of big fat electrolytic capacitors
to provide a source of diminishing power when the main power is removed.

I will display some of my circuits as I go along. Eventually I hope to present some sound clips here on my blog. This should really be fun!!

LATEST NEWS IN LARRY KEEGAN'S WORLD OF EXPERIMENTS !!!!!!

IN BRIEF:
1. Gave a talk to the QRA radio club on PIC Microcontrollers
2. Wired up a MING xmtr & rcvr & got it working
but want to package it more nicely and affix some PICs to it
3. Stripped apart som RC cars & trucks and set up an
RC system with a small relay attached to rcvr
4. Writing a PGM to read the infrared sigs from a handheld REMOTE.
Interesting article in SERVO mag outlines methodollogies.
PWM seems to be the most popular I think zero pulses are about 400 usecs
wide & ONE pulses are about 1200 usecs wide. There are about 34 pulses
& about 12 of them unique and determine the individual code
5. I'm in the process of firing up some of my other old laptops
The hell with batteries - they are expensive . I plan to solder conect
wires to the contact points where batteries would connect. They operate on
a whole range of voltages.