22-08-2013, 08:17 AM
Al, I think the Lampkin is basically a modified Hartley so far as I can make out, I had heard of it a while back but could not find a lot about it only a date reference to an article written by Lampkin himself in 1939.
The other thing is that the article written in the Tesla mag was written by Vackar (of oscillator fame) I wonder if he wrote that before or after he was credited with the Vackar oscillator circuit.
Heating copper wire before winding it on to a ceramic coil former was also interesting as an aid to inductor stability, that was a new one on me.
I remember the Oxley Tempatrimmer, I think Oxley are are still around in some form or other.
Pos and Neg temp coefficient trimmer capacitors are still available I think but I have not gone into who makes them as yet.
Lawrence.
The other thing is that the article written in the Tesla mag was written by Vackar (of oscillator fame) I wonder if he wrote that before or after he was credited with the Vackar oscillator circuit.
Heating copper wire before winding it on to a ceramic coil former was also interesting as an aid to inductor stability, that was a new one on me.
I remember the Oxley Tempatrimmer, I think Oxley are are still around in some form or other.
Pos and Neg temp coefficient trimmer capacitors are still available I think but I have not gone into who makes them as yet.
Lawrence.
