>
>Hi Chris
>
><SNIP>
>> These were excellent designs and it seems a pity that this silent key's
>> reputation is being tarnished by this wretched amplifier. As a young boy I
>> was privileged to visit Dick in his shack and to see examples of his
>> workmanship which was first rate, both electrically and mechanically.
>>
>> Dick was instrumental in the growth of the use of SSB in this country and
>> around Europe because, in those days, commercial equipment which came
>> almost exclusively from the States was beyond the means of most regular
>> amateurs.
>>
>> Just a few thoughts on a great guy.
>
>It shouldn't tarnish anyone's reputation because one circuit or
>theory offered is a bust. No one understands everything about
>everything.
>
? amen, Tom. However, unless G2DAF eventually admitted that the DAF
amplifier was basically DAFt, he tarnished himself. // Another example
is Maxwell's conjugate matching theorem. If it were 100% true,
amplifiers could be no more than 50% efficient. .
>For example, Collins had a spotless reputation of good designs,
>yet they somehow came up with a goofy idea that lifting the grids
>of a GG triode class AB2 PA with high reactance capacitors added
>"negative" feedback.
? To find out who's goofy, take a dipmeter and measure the 811A grid
resonance in a Collins 30L-1 amplifier. Short the grid to gnd capacitor
by soldering a strip of copper foil from the grid terminal to ground.
Remeasure the dip frequency. If the dip frequency decreases with the
short in place, Collins did not goof.
- later, Tom
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|