Howdy all, new guy here. I'm 97% done with building two dual channel Leach amps. It's my first attempt at something like this. All I can say is ---WHEW!! I'm doing my best not to feel like I'm in over my head! This experience reminds me of the old adage-- "How does one eat an elephant"? -------- One bite at a time-------
My first question is about the bias pot P1. Prof Leach states on his web site that you should set P1 to max resistance before power-up. Hmmmm- now would that be full counterclockwise so that the base of Q7 sees the full value of R27 and P1, or, would that be full clockwise so that the base of Q7 sees only R27? Just when I think I know what he is talking about, I can see the exact opposite clearly also. (I'm using Prof Leach's PCB's and the exact Bournes pot as called for in the parts list.) So gents, will that be full CCW, or full CW??
My second question is in regards to the general concept of "star grounding". I am modifing the original Leach plans by adding two extra PS filter caps per channel, and giving each pos and neg rail it's own bridge rectifier. So, should I run separate wires to central ground from each of the PS filter caps or bridges, or can some be tied together first, then have only one wire run to ground? I guess the question can be "Is it best to "daisey- chain" multiple alike components with only one feed wire to ground, or is it best to take each component to ground with it's own wire?
I thank you all in advance to take the time to relpy to these simple questions. I will value any and all answers.
Good Day.
My first question is about the bias pot P1. Prof Leach states on his web site that you should set P1 to max resistance before power-up. Hmmmm- now would that be full counterclockwise so that the base of Q7 sees the full value of R27 and P1, or, would that be full clockwise so that the base of Q7 sees only R27? Just when I think I know what he is talking about, I can see the exact opposite clearly also. (I'm using Prof Leach's PCB's and the exact Bournes pot as called for in the parts list.) So gents, will that be full CCW, or full CW??
My second question is in regards to the general concept of "star grounding". I am modifing the original Leach plans by adding two extra PS filter caps per channel, and giving each pos and neg rail it's own bridge rectifier. So, should I run separate wires to central ground from each of the PS filter caps or bridges, or can some be tied together first, then have only one wire run to ground? I guess the question can be "Is it best to "daisey- chain" multiple alike components with only one feed wire to ground, or is it best to take each component to ground with it's own wire?
I thank you all in advance to take the time to relpy to these simple questions. I will value any and all answers.
Good Day.