Howdy,

First things first, I'm totally new to the world of electronics. I've spent the last two weeks reading, and I'm swamped with a knowledge of electron theory ohms law and so on. However it is all just theory that I have learned, and I have a hard time putting it into practice.

I have set myself a rather easy first project that I wish to complete. I'm looking at hooking up a 9volt battery to a small device that will emit a 2 second beep every 30-60 seconds.

I was hoping that someone would be able to point me in the direction of some good reading for this project, or even direct me to some specific components to learn about.

Any assistance on this would be much appreciated.

Thanks
JuzzyDee

 

It could be done with a 555 timer, or a variety of "4000" series CMOS chips in various configurations... amoungst a multitude of solutions. Every member of this board would probably recomend a different method, but I would probably use something like a cheap PICAXE8 microcontroller, or a 4060 (counter/divider/osc) for minimum component count.

 

I've found a discovery series Multi Timer Kit.

I was wondering if having the output of this connected to a buzzer would do the trick once configured.

It's described as follows.

The circuit basically consists of a relay and a timer circuit which is programmed by connecting diodes in certain positions.


I think in the crawling stages of beginning (As they say, crawl before you can walk) this may be a good start.

This kit is $30AU, or I can get a 555 timer kit for $20AU. I dunno which is better, the 555 seems more difficult to configure for my needs.

 

I assume its a Dick Smith, or Jaycar kit. Cat number..??
It obviously has a presetable "Off" delay.... is the "on" period configurable for 2 seconds..?
Most of those kitset delays use an oscillator feeding some CMOS counter chips with jumpers or diodes to select the delay period.

 

I've found both a Dick Smith and Jaycar kit, $10 difference in price though, and Jaycar is out of stock.

DSE Kit is No. K2807

Jaycar Kit: KC5379

It doesn't mention the configurability on the site of the Dick Smith one, but it mentioned it was configurable on the Packaging when I was there today.

I'm also not sure of the voltage required on the jaycar kit, as I want to be able to run it off a 9v battery.

 

The Jaycar KC5379 is obviously ment for automotive use, so will be 12 volts. I think I recall that circuit from Silicon Chip mag, and it may be a pre-programmed PIC chip with a couple of binary switches to select the mode/delay, and a buffer to drive a 12 volt relay. To modify for 9 volts would probably only require a change of relay, as I think the rest of the circuit is probably fed via a 5 volt regulator.
The Dick Smith one seems to be a 555 timer using a pair of CMOS divider chips (configured with a diode matrix) to get the delays required.
Jaycars KA-1732 might also suit (and seems similar to the Dick Smith one, but only a single divider chip).
If it were me, I'd still use a PICAXE8 chip (about $5 worth... plus a homemade programing cable and free software) and a few simple BASIC commands later and your ready to rock.