Electronics Australia Playmaster 300
300W Amplifier Module
The Playmaster 300 was a competing contemporary of the ETI466. It is impossible to know which was the more successful; I expect it was much the same between the two. The designs are however, as different as chalk and cheese. There are merits to both designs.
At first I was put off completely by the odd, central span location of the heatsink carrying the output transistors. So I preferred to stick with the ETI466's I was building at the time. Only later did I realise that the Playmaster 300 lent itself to having a fan blowing front to back (or vice versa) through the depth of the amplifier cabinet, down the length of the heatsink. I also later noticed the low profile of the Playmaster, and contrived to "stack" two, one upon the other, within a 3RU box, producing the highest power-to-RU ratio I ever achieved as an amateur constructor. The Playmaster 300 design has considerable merit!
The following files are available here; they're zipped .pdf's, with text and figures stored separately, to minimise file-size; - you sort of have to reassemble the articles yourself!
"Errata & Corrections"