Hello Ed:
The two owners were partners at one time, now they are two separate
entities.
Command prefers triode technology, and QRO designs with tetrodes.
73 and Happy DXing,
Mike
W2AJI
----- Original Message -----
From: "Edwin Karl" <edk0kl@centurytel.net>
To: <amps@contesting.com>
Sent: Saturday, July 28, 2007 9:20 AM
Subject: [Amps] Multiple Model Numbers
> Like many manufacturers, MFJ undoubtedly wants to compete in all areas. So
> models for every one using the more popular tubes in the amps.
> Now, if you examine the design closely, the output tube module is the only
> change (other than the front panel) in the three high power amplifiers.
Sam
> Box, wires HV supply interior layout. They have modularized the amplifiers
> which I always felt was very clever.
> One of my considerations is the cost of a replacement amplifier devices
> (tubes). A pair of 3-500s is its cheaper than the other choices, that
> includes the QRO Command units and their tubes. All are lots more than the
> $300 that 3-500s cost.
> I'm a low budget kind of guy so that is a consideration.
> By the way, anyone know how come Command and QRO who seem to have close by
> addresses don't get together?
>
> ed K0KL
> ----- Original Message -----
> From: <amps-request@contesting.com>
> To: <amps@contesting.com>
> Sent: Friday, July 27, 2007 11:00 AM
> Subject: Amps Digest, Vol 55, Issue 68
>
>
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> > than "Re: Contents of Amps digest..."
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> >
> > Today's Topics:
> >
> > 1. Re: Ameritron amp purchase decision questions (Scott Manthe)
> > 2. Re: Ameritron amp purchase decision questions (shack)
> > 3. Re: Ameritron amp purchase decision questions
> > (Robert Dorchuck W6VY)
> > 4. Re: Ameritron amp purchase decision questions] (W2XJ)
> > 5. Re: Gassy Tubes/Technology Museum looking for artifacts] (W2XJ)
> >
> >
> > ----------------------------------------------------------------------
> >
> > Message: 1
> > Date: Fri, 27 Jul 2007 10:54:16 -0400
> > From: Scott Manthe <scott.manthe@gmail.com>
> > Subject: Re: [Amps] Ameritron amp purchase decision questions
> > To: R Atkins <rusty_atkins@yahoo.com>, Amps@contesting.com
> > Message-ID: <46AA0718.1090701@arrl.net>
> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> >
> > Of those choices, I'd go with the AL-80B or AL-572. I've had both and
> > both were decent amps, although I had some trouble with the 572. If you
> > go that route, I'd wire the transformed to get about 2.5 kV HV, rather
> > than the normal 2.8-3 kV, because the Chinese 572Bs don't like 3 kV.
> >
> > Nobody pays $3500 for a AL-1500 or AL-1200. Whatever someone pays,
> > they're not paying for the extra 200 watts, they're paying for the extra
> > 500 or 1000 watts, whether for headroom or actual output power.
> >
> > R Atkins wrote:
> > > Without getting into the "why would anybody pay $3500 for the
> AL-1200/1500 for 200 watts more?" questions, let me ask...
> > >
> > > Why would anybody pay $500 more for the AL-800 than the AL-572 when it
> has slightly lower power output and the tubes cost 9 times as much?
> > >
> > > .. and why would anybody pay only $100 less for 1000 rather than a
13000
> watt amp when the tubes cost 4 times as much?
> > >
> > > I'm sure I'm overlooking something here, but not sure what.
> > >
> > > Thanks!
> > > Rusty
> > > K0FE
> > >
> > >
> > >
> > >
> > >
> > >
>
____________________________________________________________________________
> ________
> > > Yahoo! oneSearch: Finally, mobile search
> > > that gives answers, not web links.
> > > http://mobile.yahoo.com/mobileweb/onesearch?refer=1ONXIC
> > > _______________________________________________
> > > Amps mailing list
> > > Amps@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/amps
> > >
> > >
> >
> >
> > ------------------------------
> >
> > Message: 2
> > Date: Fri, 27 Jul 2007 08:12:19 -0700
> > From: "shack" <noddy1211@sbcglobal.net>
> > Subject: Re: [Amps] Ameritron amp purchase decision questions
> > To: <Amps@contesting.com>
> > Message-ID: <006301c7d060$87920500$0201a8c0@shack>
> > Content-Type: text/plain; charset="us-ascii"
> >
> > The reason I have the AL-1500 is because it takes less than 60 watts of
> > drive for 1500 watts on most bands, this save running the modern 100
> > watt exciters flat out. Your right no one pays 3500 for it, more like
> > 2600. As you mention below it is nice to have the headroom, better to
> > run the 8877 at less rated max power than run a pair of 3-500's flat
> > out.
> >
> > -----Original Message-----
> > \
> > Of those choices, I'd go with the AL-80B or AL-572. I've had both and
> > both were decent amps, although I had some trouble with the 572. If you
> > go that route, I'd wire the transformed to get about 2.5 kV HV, rather
> > than the normal 2.8-3 kV, because the Chinese 572Bs don't like 3 kV.
> >
> > Nobody pays $3500 for a AL-1500 or AL-1200. Whatever someone pays,
> > they're not paying for the extra 200 watts, they're paying for the extra
> >
> > 500 or 1000 watts, whether for headroom or actual output power.
> >
> > R Atkins wrote:
> > > Without getting into the "why would anybody pay $3500 for the
> > AL-1200/1500 for 200 watts more?" questions, let me ask...
> > >
> > > Why would anybody pay $500 more for the AL-800 than the AL-572 when it
> > has slightly lower power output and the tubes cost 9 times as much?
> > >
> > > .. and why would anybody pay only $100 less for 1000 rather than a
> > 13000 watt amp when the tubes cost 4 times as much?
> > >
> > > I'm sure I'm overlooking something here, but not sure what.
> > >
> > > Thanks!
> > > Rusty
> > > K0FE
> > >
> > >
> > >
> > >
> > >
> > >
> > ________________________________________________________________________
> > ____________
> > > Yahoo! oneSearch: Finally, mobile search
> > > that gives answers, not web links.
> > > http://mobile.yahoo.com/mobileweb/onesearch?refer=1ONXIC
> > > _______________________________________________
> > > Amps mailing list
> > > Amps@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/amps
> > >
> > >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
> >
> >
> > ------------------------------
> >
> > Message: 3
> > Date: Fri, 27 Jul 2007 08:30:05 -0700 (PDT)
> > From: Robert Dorchuck W6VY <w6vy@yahoo.com>
> > Subject: Re: [Amps] Ameritron amp purchase decision questions
> > To: Amps@contesting.com
> > Message-ID: <400225.60603.qm@web53910.mail.re2.yahoo.com>
> > Content-Type: text/plain; charset=iso-8859-1
> >
> > Not any more - the AL1200 and AL1500 are $2899 or more at
> > all the major radio stores (Texas Towers, HRO, AES, etc).
> >
> > The best bang for the buck is probably the AL-80B.
> >
> > Bob W6VY
> >
> > --- shack <noddy1211@sbcglobal.net> wrote:
> >
> > Your right no one pays 3500 for it, more like> 2600.
> >
> >
> > ------------------------------
> >
> > Message: 4
> > Date: Fri, 27 Jul 2007 11:41:40 -0400
> > From: W2XJ <W2XJ@nyc.rr.com>
> > Subject: Re: [Amps] Ameritron amp purchase decision questions]
> > To: amps@contesting.com
> > Message-ID: <46AA1234.8060308@nyc.rr.com>
> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> >
> > To a degree you are looking at apples and oranges. The AL 572 uses 4
> > tubes, the RF parts replacement cost is $144 to $239 -depending on the
> > quality - not $60. The Al 80 Tube cost is $139 to $159 While you can
> > tube the AL-800 for $459. The real difference is in how you want to
> > operate. If you are only operating SSB than the differences are features
> > and tube preference. You should do some research into the future
> > availability the tubes. The most expensive of the batch - the 3cx800A7
> > is still a current Eimac product.
> >
> > If you are interested in other modes than there is a bigger difference.
> > The 80B is rated 500 watts RTTY (or many digital modes), The AL-800 is
> > rated 700 watts RTTY and has better key down specs. The AL-572 does not
> > have a listed RTTY rating. This is not just the tube capability it is
> > also the power supply rating. I have a Kenwood Linear with a 3-500
> > final. It will be replaced by either an AL-1500 or a very robust solid
> > state amp. I am still looking at those options. Since I like digital and
> > CW, I want and AMP that will sit key down at 1500 watts output for a
> > long time without problems.
> >
> > If you only operate sideband or don't care if your digital and CW power
> > is reduced than your choice might be different. Of course you also need
> > to look at the required driving power of the amps. There is no benefit
> > of having a robust amplifier if your transceiver can not drive it in
> > digital modes.
> >
> >
> > R Atkins wrote:
> > > I'm looking over all of the ameritron amps and having trouble
> understanding something... a quick breakdown reveals the following (from
> their web site)
> > >
> > >
> > >
> > > AL-80B: 1000 watts,
> > > tube cost $249. $1399 list
> > >
> > >
> > > AL-572: 1300 watts,
> > > tube cost $60. $1495 list
> > >
> > >
> > > AL-800: 1250 watts, tube cost $535. $1995 list
> > >
> > > Without getting into the "why would anybody pay $3500 for the
> AL-1200/1500 for 200 watts more?" questions, let me ask...
> > >
> > > Why would anybody pay $500 more for the AL-800 than the AL-572 when it
> has slightly lower power output and the tubes cost 9 times as much?
> > >
> > > .. and why would anybody pay only $100 less for 1000 rather than a
13000
> watt amp when the tubes cost 4 times as much?
> > >
> > > I'm sure I'm overlooking something here, but not sure what.
> > >
> > > Thanks!
> > > Rusty
> > > K0FE
> >
> >
> >
> > ------------------------------
> >
> > Message: 5
> > Date: Fri, 27 Jul 2007 11:42:20 -0400
> > From: W2XJ <W2XJ@nyc.rr.com>
> > Subject: Re: [Amps] Gassy Tubes/Technology Museum looking for
> > artifacts]
> > To: amps@contesting.com
> > Message-ID: <46AA125C.5010905@nyc.rr.com>
> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> >
> > It was mentioned earlier in the thread that the 7th pin was to prevent
> > 807s from being plugged in by mistake.
> >
> >
> >
> > Karl-Arne Markstr?m wrote:
> > > It appears that the date quoted on the German web-site for the 1625
was
> > > wrong.
> > >
> > > In the 1942 edition of the "RCA Guide for Transmitting Tubes" that
> > > went to press
> > > in October/November 1941 the 1625 was included and
> > > was described as "Similar to 807 but has 12.6 V heater ... Especially
> > > Useful in Aircraft Transmitters"
> > >
> > > So the 1625 was around before Pearl Harbor.
> > >
> > > Any reasons for RCA to choose the 7-pin base for the 1625 were not
> > > mentioned, and they are probably buried deep into the sediments of
> > > corporate logic. My guess is as good as anyone elses.
> > >
> > > Regarding the 8018, it seems to be an interesting variation of the
> > > 807.
> > > I found some variants, one with a normal phenolic base but quoting a
> > > higher transconductance than the "regular" 807, and two with ceramic
> > > bases, the RAF VT-60 and VT-60A.
> > >
> > > The electrode system in the VT-60 shown at http://www.tubecollector.
> > > org/vt60.htm
> > > appears to be somewhat "skinnier" than the regular 807. If this may
> > > have affected the VHF performance is uncertain.
> > >
> > > 73/
> > >
> > > Karl-Arne
> > > SM0AOM
> > >
> > >
> > >
> > >
> > >
> > >
> > > ----Ursprungligt meddelande----
> > > Fr?n: g3rzp@g3rzp.wanadoo.co.uk
> > > Datum: Jul 27, 2007 11:20:22 AM
> > > Till: amps@contesting.com
> > > ?rende: Re: [Amps] Gassy Tubes/Technology Museum looking for artifacts
> > >
> > >
> > >>Wild guess: to prevent plugging a 6.3v filament tube in a 12.6v
> > >
> > > socket?
> > > Maybe 807's were also used in other applications in that era.<
> > > It seems a bit illogical, because there were 6 and 12 volt octal
> > > tubes with the same base connections - 6K7, 12K7, 6SG7, 12SG7 etc.
> > > Further back, there were 2.5 volt and 6.3 volt tubes on the same UX
> > > base - 2B7 and 6B7 come to mind. So why go to the bother for 1625s,
> > > when they needed more metal for the two extra pins? And the quantity
of
> > > 1625s made meant that must have been a fair weight of brass for those
> > > two extra pins.
> > > 807s were around pre war, and there was one of the early RAF VHF
> > > transmitters used something called an 8018, which my father told me
was
> > > an 807 selected for more output at 120MHz - he actually instructed on
> > > that equipment when he was in the RAF. He said it was awful speech
> > > quality, using the device as a sort of linear with low level grid
> > > modulation on the preceding frequency multiplier, and running grid
> > > current in the 8018.
> > > 73
> > > Peter G3RZP
> >
> >
> >
> > ------------------------------
> >
> > _______________________________________________
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> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
> >
> > End of Amps Digest, Vol 55, Issue 68
> > ************************************
> >
> >
> >
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