View Single Post
  #20 (permalink)  
Old June 13th 16, 07:54 AM posted to uk.rec.audio
Phil Allison[_3_]
external usenet poster
 
Posts: 312
Default Germanium Hi-Fi amp ??

Eiron wrote:


I became quite adept at fixing Z30s in my youth.
http://rk.nvg.ntnu.no/sinclair/audio/z30.htm
Maybe a much bigger heat sink would have helped
but they hardly ever survived a party.


** Someone gave me one Z30 module and a "Project 60" manual in the early 70s - it all sat in a drawer for several years until I figured out a use. In the manual was a schem for making the Z30 into a power sine wave oscillator using a Wein bridge circuit. See figure 4.16.1.a

http://www.epanorama.net/sff/Audio/C...oject%2060.pdf

I quickly lashed up one built to oscillate at 67Hz, with a few Hz range of adjustment. Used with an unregulated 30V supply, it ran nicely with the output feeding the 8ohm winding of a 15W UL output tranny from an old valve amplifier.

The primary was used to drive a small synchronous motor with a 240V pure sine wave. The finished version had a toggle switch to bring the frequency down to a nominal 50Hz.

This is a pretty tough job for a puny Sinclair Z30 module, but it never failed in over 20 years of use.

Who can guess what it did ?


..... Phil