From: W. Daniel, 9V1ZV (email@example.com)
On Fri, 18 Aug 1995 17:43:09 EDT, "Richard G. Kellner" <firstname.lastname@example.org> wrote:
> the push-pull circuit are not contributing equally; one side is way down.
I built on of them things about a year back or so. Samething.
Instructions were wrong etc etc. In any case I felt that the layout was
unstable with long lines running both the input and output. Input and output
coupling was a real likelyhood as is parasitic osc. I finally redesigned the
whole circuit on a PCB about 1/3 the original size. This has worked much
better and was giving me a little over 15 watts (depending on the power
supply) with reasonable stability. Only problem is still the biasing, the
MTP3055E's got REALLY hot after a little bit of usage. I am not sure how to
fix the biasing, and tried a few things but none seemed to make a great deal
of difference. Most likely it is a design flaw somewhere. BTW, my own PCB
design had a ground-plane for the reverse side of the PCB. I can't remember
what the signal looked like on the scope now.
73 de 9V1ZV Daniel
-- Daniel Wee | email@example.com 9V1ZV | firstname.lastname@example.org
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