Juma PA-100D Version 4.01a

[5B4AIY]

This is a maintenance build, and does not add any new features. An examination of the code showed that there was a very remote 'window-of-opportunity' for an error to cause garbage to be sent on the serial port to a connected transceiver in the AUTO frequency sense mode. I hasten to add that in now more than 10 years of operation and literally hundreds of user downloads I have never encountered this possible fault, but I learned a long time ago in software that if the probability of occurrence is not absolutely zero, then it is certain to occur sometime. So, in the interests of defensive programming, I made a change to two modules to add a further layer of protection. You can examine the source code for the xmit_cmd() function and the *poll_cmd[] message array, as well as the explanation at line 563 of the juma-pa100.c source file if you are interested.

This code can be safely loaded over a previous version 4 without provoking a checksum error on start-up. If you are updating from an earlier revision, then as the EEPROM mapping has changed this will provoke a one-time checksum error and load the standard defaults on initial power-up. Make a note of your existing calibration and configuration data before updating to avoid having to re-calibrate. There are pages at the back of the User Manual specially set aside for this data.

NOTE: I have now been supplied with the source code of the modifications from Rowaves Technologies, and can confirm that it is merely cosmetic, and has no impact on the operation of the amplifier. As a result, this version of the firmware should work perfectly well, but please note that it has only been tested on an original Juma PA-100D kit. As with all firmware updates, therefore, use at your own risk. (23-DEC-2021)

Adrian, 5B4AIY