This project first appeared in RadCom - October 2015. To program the PIXACE used in the project with this code you will need to download one of the PICAXE editors found at http://www.picaxe.com - see the "Free Software" button top right. You will also need a programming cable that can be purchaced from http://www.techsupplies.co.uk.
If you don't want to go the trouble of buying the programming cable then I can supply pre-programmed PICAXE chips at a cost of £4.00 each - including P & P. Either send a cheque to the address below or make a PayPal payment to email@example.com.
Martin Waller Olive Cottage, 6, Church Road, Chelmondiston, Ipswich, Suffolk, IP9 1HS
If you have trouble with either mechanism then please contact me on Martin@The-Wallers.net
The transistor labelled TIP20 should be labelled TIP120.
If you decide that you will not be wanting to re-program the PICAXE in situ then you can do away with the programming socket and the two resistors 10K and 22K. What will need to do is to ground pin 3 of the PICAXE. This is the Serial-In and if left floating strange things can happen!
You can turn the circuit into a simple Morse oscillator if you wish. This has been done by incorporating a switched 3.5mm mono jack socket. The switch is used to cut off the power from the PICAXE (Pin 14) and to short across the TIP-120.
If you wish to add an earphone socket then this is best done using a switched 3.5mm mono jack socket and configuring it across the speaker.
David, G4EDR, has sent in a picture of his completed build.