I've always said, a person has the choice: Be loud or be good.
It's much easier and much less expensive to be loud than good.
73
Bob K4TAX
Hans Goldschmidt wrote:
>
> 1-02-26 04.50, skrev measures på 2@vc.net följande:
>
> >
> >>
> >> measures wrote:
> >>
> >>> I ran a pair of paralled 4cx250Rs on 2m SSB. The tank was 1/4 wave.
> >>> With a screen current of c. 5mA (@400screen-v), the linearity was good.
> >>> Output was c.900w PEP on SSB. 10w drove it.
> >>>
> >>> cheers
> >>>
> >>> - Rich..., 805.386.3734, www.vcnet.com/measures.
> >>
> >> I think in these arguments (anf it seems to have developed into that),
> >> it is essential to define what 'good' is.
> >
> > Good means no splatter complaints from nearby staions.
> >
> >> It's a bit pointless saying
> >> 900 W at good linearity, without defining what 'good' is. Does 'good'
> >> mean that it did not sound distorted at the other end, or that the 3rd
> >> order products were more than x dB down ?
> >>
> > none of the above
> >> Without 'good' being defined, there is little point is arguing about
> >> whether a single 4CX250B can produce 250, 300, 450 or even 1 kW. I took
> >> a data sheet figure of 300 W, but clearly there is some tradoffs between
> >> power/linearity/tube life/voiding tube warrenty/and a whole host of
> >> other things.
> >>
> >> --
> >> Dr. David Kirkby Ph.D,
> >> email: drkirkby@ntlworld.com
> >> former email address: davek@medphys.ucl.ac.uk
> >> web page: http://www.david-kirkby.co.uk
> >> Amateur radio callsign: G8WRB
> >>
> >> --
> >> FAQ on WWW: http://www.contesting.com/FAQ/amps
> >> Submissions: amps@contesting.com
> >> Administrative requests: amps-REQUEST@contesting.com
> >> Problems: owner-amps@contesting.com
> >>
> >>
> >
> >
> > - Rich..., 805.386.3734, www.vcnet.com/measures.
> > end
> >
> >
> > --
> > FAQ on WWW: http://www.contesting.com/FAQ/amps
> > Submissions: amps@contesting.com
> > Administrative requests: amps-REQUEST@contesting.com
> > Problems: owner-amps@contesting.com
> >
> >
> It is about time to try to modify the 2 meter K2RIW to use, if possible, the
> 4CX400. If my memory is right, was there not already an article on using the
> 8930 = same tube as the 4CX400?
>
> Come over here to Scandinavia when we have our monthly tuesday 2 meter
> contest. Very few guys know nowadays anything at all about linearity and
> wide splattering signals are accepted. There has even been guys using FM
> transistor amps in SSB!!!
>
> Years ago when I had a super QTH in southern Stockholm high up overlooking
> Stockholm, I had to give up 2 meter contesting because the wide signals. The
> worst thing was, that the offending stations did not go QRT after receiving
> a polite complain but just continued calling. Even when I told them I
> listened with an attenuator in series with the receiving ant to bring down
> the signal to a S9 level to avoid receiving overloading. And came back in
> the next tuesday contest with the same signal quality!
>
> Sorry to say we must accept this situation to some degree as we can not
> demand hams should have the same knowledge as the commercials and use
> expensive spectrum analyzers. But a guy that is wide as a barn door even
> when beeing only S9 and receives a lot of complains from hams who know how
> to check signals. He HAS to do something. Why? Because it reflects back to
> his own QRM situation when bad signals are beeing accepted as something
> normal.
>
> I would like to try the new TS 2000 on 2 meters with reduced power to 40 -50
> watts to drive a 8877. Wonder what the linearity of the 2000 would look like
> in 50 watts out and what about the relation peak power out to noise
> sidebands when reducing power??
>
> Prosit de Hans SM5KI
>
> --
> FAQ on WWW: http://www.contesting.com/FAQ/amps
> Submissions: amps@contesting.com
> Administrative requests: amps-REQUEST@contesting.com
> Problems: owner-amps@contesting.com
--
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