A Note about "ROUGH TONE"

By today's standards, it might appear that having a "rough tone" was just nit-picking by the Official Observer. While a rough tone could be caused by an inadequately filtered power supply, it might also indicate the very serious problem of parasitic oscillations.

That early lashup of three separate transmitting units - VFO, exciter, amplifier, was a particularly gruesome one. The antenna was not mentioned but it was some sort of random wire/Windom configuration that should have been used only with an adequate RF ground system. Such a ground system was difficult to obtain in a third floor apartment with outside antenna restrictions.

Combining the poor antenna system with the three separate amplifying units all operating at the fundamental frequency with lots of unneeded amplifying gain might have led to unwanted oscillations and hence, the rough tone.

Back then the shortwave spectrum was filled with miscellaneous beeps and boops, generated by a myriad of man-made devices.  The ARRL Official Observers helped to ensure that the amateur stations were not a major source of this spectrum pollution.   So hearing a rough tone on the air and informing the operator of the condition was a very valid service.  Thanks again, Ed.

I eventually upgraded to better equipment - a Knight V-44 VFO and a Johnson Challenger transmitter (minus the Globe amplifier).

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