Rich says:
>tuning up with a 30% - 50% duty-cycle pulse is not a bad way to go
I think that depends. Let's assume that your amp can produce the full wack
single tone when tuned for 10 seconds or more - then if you're reasonably quick,
you can do quite well without.
However, years ago I worked at a firm that made ham gear as well as
'professional' stuff. One customer, an old chap, who must have been in his mid
70's, had trouble with his amp blowing up. So they sat him down in the service
department and got him to tune it. He switched to transmit, raised the drive
until the PA plate meter read half scale, and then, I kid you not, proceeded to
fill and light his pipe! Having got that smoking like a hard working Union
Pacific Big Boy on Sherman Mountain, he then started the tune up procedure -
very slowly, and stopping to read the book after every adjustment.
I doubt that even Rich's pulser would have helped enough in that case!
>// ... 60% is fairly common in Class AB_ with unpusillanimous anode
>potentials.
I said give or take - the principle is the same that efficiency drops at low
outputs.
Time for me to take off for the weekend. Have a good weekend, guys. I'll read
the mail Monday morning.
73
Peter G3RZP
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