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previous: Enzo I wouldn't assume it is common just... -- 9/29/2004 3:16 AM

Re: Fender Deluxe Reverb RI Oscillation

9/29/2004 1:43 PM
Brad	Re: Fender Deluxe Reverb RI Oscillation Thanks for the reply. It is not caused by the environment, power quality or local equipment (good suggestions though). Although I'm an EE, I don't have a scope at home and I can't get my amp into a classified area. So for the time being, I'll be flying blind: No scope. As far as not being common, I'll take your word for it. In fact, that's why I posted here: I knew if it were common the root cause and fix would be known by experts like you(like the tremolo tick di/dt problem and cap. fix) Sorry about the misunderstanding regarding parasitic oscillation. I think I recall back in my Radiotelephone license days (that dates me) burst oscillations being referred to as parasitic. In my present field of the last 25 years, the parasitic simply refers to stray circuit RLC that, when coupled with unity gain amplification and 360degree phase shift, can support an un-intended oscillation for any length of time. I'm sorry to say in our present ultra-high bandwidth world we've accidentally built a few of these into our otherwise digital circuits! I suppose over the years we've basterdized the original meaning. Thanks for the response. Brad

9/29/2004 1:43 PM

Brad

Re: Fender Deluxe Reverb RI Oscillation

Thanks for the reply. It is not caused by the environment, power quality or local equipment (good suggestions though).

Although I'm an EE, I don't have a scope at home and I can't get my amp into a classified area. So for the time being, I'll be flying blind: No scope.

As far as not being common, I'll take your word for it. In fact, that's why I posted here: I knew if it were common the root cause and fix would be known by experts like you(like the tremolo tick di/dt problem and cap. fix)

Sorry about the misunderstanding regarding parasitic oscillation. I think I recall back in my Radiotelephone license days (that dates me) burst oscillations being referred to as parasitic. In my present field of the last 25 years, the parasitic simply refers to stray circuit RLC that, when coupled with unity gain amplification and 360degree phase shift, can support an un-intended oscillation for any length of time. I'm sorry to say in our present ultra-high bandwidth world we've accidentally built a few of these into our otherwise digital circuits! I suppose over the years we've basterdized the original meaning.

Thanks for the response.
Brad