[theme : Applications] [author : Grappel-Hemenway]
[theme : Applications] [author : Sewell]
[theme : Applications] [author : Filgate]
[theme : Software] [author : Guthrie]
[theme : Applications] [author : Hickey]
[theme : Speculation] [author : Hosking]
[theme : Applications] [author : Krakauer]
[theme : Hardware] [author : Baker]
[theme : Philosophy] [author : Fylstra-Wilber]
[theme : Organizations] [author : Douds]
About the Cover
As a way to highlight the history of electronic digital signalling, we dug up a picture of one of Jose ph Henry's original telegraphy keys, circa the early 1800s. Robert Tinney then placed the key in the frame and wall setting you see on the cover, using a photo supplied by Brian McCarthy.
The problem of decoding arbitrary hand generated Morse code is not a trivial one. It requires some care and thought in the design of adaptive algorithms. As one contribution to this issue's sub theme of computerized Morse code, Lt Willi am A Hickey, USN, provides some background information and suggestions on the subject.
W J Hosking, W7JSW, is an amateur radio operator in search of applications hardware and software. Read about A Ham's Application Dreams and find out how to implement one aspect of his dream with the Morse code input and output conversion technology described in detail in the balance of this issue ... .
A theme of this October issue is the application of microcomputers to the decoding of Morse code. One approach to the problem is detailed in Robert Grappel and Jack Hemenway's article on MORSER... a program to read Morse code, implemented with a Motorola 6800 computer. Lawrence Krakauer describes a technique to store Morse characters as a packed table of bit patterns for machine generated outputs - or for machine decoded inputs.
If Only Sam Morse Could See Us Now. He'd have a fistful of problems trying to copy radio transmissions at 1000 wpm generated by programs such as Way ne Sewell's CWBUFFER subroutine. But, using one of Wayne's set of sundry drivers for CWBUFFER, Mr Morse could potentially learn to copy - or at least have his computer copy - in a code practice mode.
One application of the Morse code problem solvers is documented in Bruce Fil gate's article on Morse Code Station Data Handler. This is an application program which handles direct sending of Morse outputs, from character text, adaptive interpretation of Morse inputs, storing of fixed messages (eg: ' CQ CQ CQ DE W1AW ') in a message buffer for later transmission or repetitive transmission, etc. Bruce has put it all together in the form of a comprehensive 1536 byte program for an 8008.
Once you sit down and Build This Mathematical Function Unit as described in part one of R Scott Guthrie's two part article, the world of high level mathematical functions is opened to your microcomputer. In part two this month, the software needed to interface with the calculator is described, as well as several test loops used to adjust timing parameters with an oscilloscope. As a final illustration of the calculator's use, the author provides a program called CALCULA which enables a Teletype (or other ASCII) port to drive the calculator and print results, simulating the ordinary hand calculator level of operation .
National Semiconductor announced the PACE computer some time ago, but until recently it has been somewhat hard to obtain . Now that this 16 bit minicomputer is beginning to enter its volume production stage, we Keep PACE With the Times by offering Robert Baker's Microprocessor Update on this processor. If you missed the convenience of your familiar 16 bit minicomputer when you started reading about and "dry run programming" for personal computing, then the PACE processor might be a logical choice for a homebrew or kit system.
The advent of the personal system portends a fundamental change in the ways computers are used. In Homebrewery vs the Software Priesthood, David Fylstra and Mike Wilber make some comments about the impact of widespread use and knowledge of computers.
Looking for ideas for meetings of your local computer group? Dr Charles F Douds has a few suggestions to make in his background article on the subject this month.