>
>Lars Harlin wrote:
>>
>>AG6K:
>>> ? not according to DAF recommendations.
>>
>>SM3BDZ:
>>And exactly WHAT is the DAF recommendations??
>>
>Only what G2DAF himself wrote (copy posted on my web site). All the rest
>has come from other people, and G2DAF is not around to pass comment.
>
>Actually, that's probably just as well for some people, because G2DAF
>was a totally ruthless critic of SSB signal quality.
? It would have been my guess that DAF would be on a submission and
domination trip.
> Anyone who checked
>into his 80m SSB Experimenters net "for a signal report" could expect no
mercy!
>
? The only was I know to deal with S&D freaks is to be very certain of
your stuff beforehand, do not partake of puerile insults of any kind
whatsoever, and never, Ever become angry. Remember that in a debate,
everyone who chooses the Insult Card looses.
>
>....... Because the gain depends on
>the 3/2 power of the screen voltage, as Rich said, the transfer
>characteristic of the G2DAF-type amplifier cannot be a straight line. It
>has to be S-shaped - starting with low gain at low signal levels (and
>therefore low screen voltage), increasing for medium levels, and then
>flattening off like any amplifier does if over-driven.
? well put
>
>This might explain why the two-tone results from DAF-type amps can look
>reasonable at high (but not excessive) drive levels. At lower drive
>levels, the IMD relative to the output level could be significantly
>worse. An oscilloscope pattern of the two-tone signal would presumably
>show significant "pinching" of the crossovers as the gain drops... but
>the output level is lower, so maybe it matters less? What this means for
>a real-life speech signal is hard to guess.
>
? -20 to -23 db is apparently a pretty good guess.
cheers, Ian.
- Rich..., 805.386.3734, www.vcnet.com/measures.
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