The only differences I can see are QSK, automatic bandswitching and a
built in speaker. But then there's the "Legendary" MFJ quality to deal
with.
Steve N4LQ
----- Original Message -----
From: "Al Williams" <alwilliams@olywa.net>
To: "John - G3JAG" <patents@dx0man.prestel.co.uk>; "Jim Reid"
<kh7m@hsa-kauai.net>
Cc: "M. Clark" <rudder@gulfcoast.net>; <tentec@contesting.com>; "Greg
Hodsdon" <k7kj@teleport.com>
Sent: Saturday, January 01, 2000 1:32 PM
Subject: Re: [TenTec] Hercules II Power Source
>
> For the first time since my Argonaut 505 days, I have been thinking
> about adding an amplifier-- to my Omni6+. What benefits derive from
> purchasing the Hercules over Ameritrons far cheaper 500w 12v
> all solid state amplifier?
>
> k7puc
>
>
> -----Original Message-----
> From: John - G3JAG <patents@dx0man.prestel.co.uk>
> To: Jim Reid <kh7m@hsa-kauai.net>
> Cc: M. Clark <rudder@gulfcoast.net>; tentec@contesting.com
> <tentec@contesting.com>; Greg Hodsdon <k7kj@teleport.com>
To: <tentec@contesting.com>
> Date: Friday, December 31, 1999 6:10 PM
> Subject: Re: [TenTec] Hercules II Power Source
>
>
> >
> >The power gain is not necessarily exactly the same for different
Herc
> >IIs. The final transistors are matched by TT, but two sets may well
not
> >have the same gain. TT can and do adjust the gain, but only into
the
> >same ballpark, not to complete identity.
> >
> >It is also affected by the actual voltage reaching the finals, as
> >opposed to what the PSU puts out. When you say 14 volts from the
9420,
> >that is the voltage each rail should be set to internally, at the
> >respective capacitor terminals. TT say not to set it any higher (to
> >compensate for voltage drop in the cables) as that will upset the
> >control circuitry. It follows that the voltage at the finals will
> >always be less than 14. How much less depends on the resistance in
> >circuit. In my case, I discovered that there was at least one
> >intermittent dry joint in the Herc II distribution/relay board. The
> >effect was to create a spectacular imbalance in the amplifier, one
pair
> >of finals getting practically no power under load.
> >
> >Incidentally the dry joint was apparently not a recent development;
it
> >may have been responsible for the self-destruction of two finals
some
> >time back.
> >
> >If you see low gain, then it may be worth opening the Herc up and
> >checking carefully for any problem in this area. I re-soldered all
the
> >rivetted connections, relay terminals etc. on the control board
after
> >measuring some strange variations in standing current (I think it
> >should be exactly 1/2 amp per set of two finals - the individual DC
bias
> >voltages are NOT a reliable guide to actual idling current). I also
had
> >this intermittent and humongous voltage drop for one pair under
load.
> >
> >Its a tedious job and needs a large soldering iron, but in my case
it
> >was well worth the effort.
> >
> >John G3JAG
> >
> >On 31-Dec-99 Jim Reid wrote:
> >>
> >> Gregg, K7KJ wrote:
> >>
> >>> Jim:
> >>> Just checked my 10 year old Hercules II/9420 PS on 7.025 into a
> >>> dummy
> >>> load using a VFD wattmeter: 26w in/ 540w out, 35w in/ 600w out,
and
> >>> will
> >>> put out well over 600w (with the red LED on!). Keep in mind the
9420
> >>> puts out 14.0 vdc, no load.
> >>
> >> Now that is interesting, Gregg. That is exactly 13 dB gain on
the
> >> first pair, and 12.3 dB on the second. My numbers show my
> >> solid state amp is producing only about 8 dB gain, hmmmmm?
> >> Yes, 84 in, 570 out is only a numerical gain of 6.8x's, or some
> >> 8.3 dB. I can crank the Astrons up to 14 vdc, but probably
won't.
> >>
> >> Herc. II typicals from the TT web page:
> >>
> >> "RF Power: 1000 watts input. 500/600 watts output, depending
> >> on frequency and load impedance.
> >>
> >> Drive Power: 65 to 80 watts typical for 500 watts output.
> >>
> >> (Or a typical Herc. gain of around 9 dB down to only 7.9dB,
> >> with 80 in and 500 out)
> >>
> >> Primary Power: RF deck, 12 to 14 volts at 100 amps, maximum"
> >>
> >> Your Herc. II at 13 dB gain is a real "hot one", Gregg, hi.
> >>
> >> Does the 9420 PS have a current meter, if so, how much
> >> current is being drawn?
> >>
> >> Happy New Year and 73, Jim, KH7M
> >> On the Garden Island of Kauai, temp outside: 75 F.
> >>
> >>
> >> --
> >> FAQ on WWW: http://www.contesting.com/tentecfaq.htm
> >> Submissions: tentec@contesting.com
> >> Administrative requests: tentec-REQUEST@contesting.com
> >> Problems: owner-tentec@contesting.com
> >> Search:
http://www.contesting.com/km9p/search.htm
> >
> >----------------------------------
> >E-Mail: John - G3JAG <patents@dx0man.prestel.co.uk>
To: <tentec@contesting.com>
> >Date: 01-Jan-00
> >Time: 01:44:06
> >
> >This message was sent by XFMail
> >----------------------------------
> >
> >--
> >FAQ on WWW: http://www.contesting.com/tentecfaq.htm
> >Submissions: tentec@contesting.com
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> >
> >
>
>
> --
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>
>
--
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