What a lovely job you have made of the amp, Jeremy - as Jeffrey says, very professional looking. But how does the input get into the amp?
I made one of these when I was about 19 while I was at the BBC training school in Evesham. One of the lecturers, Brian Pover, let me use his workshop in the evenings to make it. It wasn't a real kit but a chassis and transformer bundle. I worked very well after a bit of fettling. The main main problem, I realised soon after putting it into home use, was parasitic oscillation at about 1.5MHz (or MC/S as it was then) which I discovered when leaving a record playing in the living room, I noticed that the same record was playing on a radio I was messing about with. I thought that it was mere coincidence except that the next track played as well. The oscillation was cured by adding a 100pf cap. from each ECL86 pentode section to ground - all completely silent (and sounding less edgy, of course.
The idea of starting with a chassis is very good.
I made one of these when I was about 19 while I was at the BBC training school in Evesham. One of the lecturers, Brian Pover, let me use his workshop in the evenings to make it. It wasn't a real kit but a chassis and transformer bundle. I worked very well after a bit of fettling. The main main problem, I realised soon after putting it into home use, was parasitic oscillation at about 1.5MHz (or MC/S as it was then) which I discovered when leaving a record playing in the living room, I noticed that the same record was playing on a radio I was messing about with. I thought that it was mere coincidence except that the next track played as well. The oscillation was cured by adding a 100pf cap. from each ECL86 pentode section to ground - all completely silent (and sounding less edgy, of course.
The idea of starting with a chassis is very good.
Cheers
Brian
My wide-band IF problems are no more - now I've got others!
Brian
My wide-band IF problems are no more - now I've got others!
