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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> 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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> End of Amps Digest, Vol 55, Issue 68
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