On Mar 18, 2005, at 6:40 PM, VK3HE Craig wrote:
> If you concerned about IMD use the 4cx1500B. At low screen potentials
> it
> has a good figure of -43 db below one of 2 tones. Nothing would
> prevent you
> using the full screen potential with output power and IMD figures being
> similar to the 4cx1000A. The radios IMD will always be greater than
> the
> tubes IMD, unless you using something like the FT1K5 in classA. These
> days
> ALC design faults are more responsible for bad IMD than the below
> average
> IMD numbers of the radio.
Amen, Craig -- ALC design faults can be countered by using the lowest
level of ALC that is detectable. This, however, is considered an
anathema on the 11m band. In actual practice, using a typical
post-xcvr amplifier, running less ALC produces more PEP to the antenna
than is the case with running maximum ALC.
>
> Craig
> VK3HE
>
> _________________________________________________________________
> Express yourself instantly with MSN Messenger! Download today it's
> FREE!
> http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
Richard L. Measures, AG6K, 805.386.3734. www.somis.org
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|