Murray Greenman CSc ZL1BPU/ZL1EE
Waiuku, Franklin, New Zealand [RF72is]
There is also a section on propagation studies, and some fascinating micro-controller projects to build. The site also hosts Amateur PC software developed by Con Wassilieff ZL2AFP/ZL2EE.
A collection of more than 40 classic and interesting receivers from 1924 to today, with descriptions, photographs and other information.
The modes described here are visually readable, rather than interpreted by electronics or computer. Although some of the modes are new, the idea isn't, and all are fascinating. This is the acknowledged premier site for Hellschreiber techniques.
Most of these modes are for conversation between two or more Amateurs. The emphasis is on performance, especially with low power or under poor radio conditions. This is the official source of MFSK16, DominoEX, EXChat and WSQ documentation.
Narrow Band TV is similar to SSTV, except that sequential frames are transmitted, and the emphasis is generally on speed (in order to provide realistic motion) rather than image resolution. Several different and highly successful full colour modes are presented.
An extensive introduction to ionospheric propagation. A small collection of techniques and ideas to assist understanding and monitoring of ionospheric propagation. The techniques include passive chirp sounding, PN ranging, narrow-band digital and carrier frequency Doppler analysis.
Here you will find the most complete collection of radio software from Con ZL2AFP, including CMSK, DominoEX, the Narrow Band TV modes, and a collection of useful utilities. There is also a selection of utilities by Murray ZL1BPU.
A Communications Receiver collection you can browse on-line or visit in person. Full construction details of a transverter and transmitter for the 630 metre band.
Receiver Collection MF Transverter & Transmitter
Adaptations for surplus high stability Rb references; recycling crystal-controlled HF SSB radios for Amateur bands; transmissions for investigating radio propagation; my MEPTs in detail.
Rubidium Synthesizers Recycled Radios ZL1EE MEPT Transmitters
Selected Amateur Radio related documents by ZL1BPU.
These pages have been written using a simple text editor, for minimum file size and maximum speed.
I believe web pages should be simple, clear, quick to load and easy to use. For bells and whistles look elsewhere.
Most recent update 20th November 2017.
My thanks to the folks at for hosting my stuff.