> > I also question the need for the extra 50 watts. I believe it takes a
> > 3dB increase to be detectable by the human ear, and about 6 dB to
> > equal one 'S' unit increase. So, 150 vs 100 watts is mostly
> > marketing/advertising hype with virtually no benefit to the user - but
> > a slight benefit to the power company :-).
>
> Thank you. That verifies what I thought I knew to be true.
Except the facts are not quite that clear ... the 3 dB figure is open
for debate ... look how many ops work to improve their stations for
the next 1 dB in gain ... also very FEW S-meters use 6 dB per unit.
1.7 dB on some meters might be 1 or almost 2 S-units ... AGC/AVC
systems can make "detectable by the human ear" differences to
be masked by the time the signal hits the audio stages of the rig.
> > It takes far less than the 100 watts that is available from my Omni
> > VI/3 to drive my Heath SB-1000 (a single 3-500) to full power output
> > on any band. I usually have it "coasting" along at about 50 watts
> > when I use the amp.
>
> This is the class of amplifier others are claiming needs the extra
> drive, is it not?
Nope. Many of the comments were for TWO x 3-500z amps. And
some design requires more than 100 watts drive for 1.5 kw out.
The AL-80/SB-1000 is a SINGLE 3-500z, so it would have roughly
half the drive requirements, especially on 10m. As other had posted,
using some amps on the WARC bands requires even more drive.
Some amps have gain factors from 8 dB to 14 dB, depending on
band and condition of the tube(s). There's no hard rules here.
> I would also prefer to see the devices run conservatively to insure
> maximum longevity, so even if the can handle 150W, 100W may
> be a much better idea.
Which for contesting ... running a 150w rig at 100w is a plus also for
long periods of time. Or for modes like RTTY with a high duty cycle.
The "plus" of a 100 watt PA is that TenTec has a very solid design,
with QSK, that is well proven over the years. It makes sense to use
that as part of the Orion platform from a design viewpoint. Yet the users
(read $$$$ purchasers) are asking for a feature that has benefit to them.
So it's a tough call for certain. The Orion is probably NOT the platform to
try out a new unproved 150w PA ...
My 2 cents ...
73 Billy AA4NU
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