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Title: Has anyone built their own Kleinulator kit Post by: hywelg on November 29, 2008, 09:39:48 PM I'm doing that at the moment, building it into a rack chassis. According to Nik I need to adjust the trimmer to bias the FET. How do you do that? Simple instructions appreciated :-[
He gave figures of 20-22Vdc though I think he must mean mV surely? TIA Hywel Harris Title: Re: Has anyone built their own Kleinulator kit Post by: erwin_ve on November 29, 2008, 11:37:33 PM You should bias the Fet with half the voltage of the power supply.
Edit: I build an old "public domain" model. I think the commercial design is different. Title: Re: Has anyone built their own Kleinulator kit Post by: hywelg on November 30, 2008, 12:07:44 AM How do I measure the bias voltage? All I know is that the FET has 3 pins and a flat on the body. Do I measure pin to ground or pin to pin? I know sod all about the electronics of these things I'm afraid so I'd be very grateful if you could be very specific.
Thanks Hywel Harris Title: Re: Has anyone built their own Kleinulator kit Post by: erwin_ve on November 30, 2008, 02:09:35 PM The bias voltage is measured from drain to ground. So you measure between, from the trimpot lug going to the fet, and ground. Hope this helps.
Mind; I build the public domain version; I don't know how the commercial is build. Maybe a different approach to both FET. How do I measure the bias voltage? All I know is that the FET has 3 pins and a flat on the body. Do I measure pin to ground or pin to pin? I know sod all about the electronics of these things I'm afraid so I'd be very grateful if you could be very specific. Thanks Hywel Harris |