Latest Projects
This Page is 'Under Construction'.
NEW Portable UHF Transceivers - restoring 1980's Hardware
Changes to this page
I am going to re-construct this page. It has been neglected for a very long time.
I think maybe that we should have a two-way choice, Hardware and Software.
This then would give the updated programs that we (Radio Amateurs) use and have used a chance to be made compatible with the later Operating Systems.
Any suggestions can be sent to me John Brock.
Latest Projects (not so)
The Morse Transmit and Receive software.
Morse Transmit program
I demonstrated the transmit program at the last Ham-Comp meeting in August.
This 'Beacon' program was written in QuickBASIC 'a long time' ago...
It works quite well even now though. Even under Windows 98. For use under other operating systems, useDosBox.
It not only allows the user to try out various messages, it also creates an INTEL hex file for programming an EPROM.
The Morse beacon digital circuit is based upon a small EPROM being stepped through it's locations.
The data lines are used to key the transmitter circuit, frequency modulate the transmitter at 800Hz as well as send Morse as a keyed tone.
You will be able to download it as a BASIC source file later here.
I modified it recently to smooth out the rough edges before I gave it to Romeo (ZS6ARQ).
Morse Receive program
The receive program I have had working but also a long time ago.
It was written in the early days of the IBM PC by AA4L.
Original program listing with comments.
So when I was planning to demonstrate it at the Ham-Comp meeting - of course it didn't work!
I shall modify it along the lines I talked about today.
With the port configurable as well as bit mask for the input.
So by the time the next 'Bring and Fix' meeting comes around, I hope to have a working model for the club to see.
The Direct Conversion Receiver for 80 metres.
The DC RX project has progressed quite well over the last couple of weeks.
The original circuit isherealong with all the comments.
- The VFO which runs at half the input frequency has been tested and finalised.
Its stabiliser is now a 7805 with a led in the ground leg connection.
This provides a very stable 6.8 Volts for the oscillator transistor.
Here is the circuit :-
- The low level audio amplifier has been planned and drawn.
Here is the circuit :-
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