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SUMMARY- Best amp for DXpedition

Subject: SUMMARY- Best amp for DXpedition
From: KA9FOX@aol.com (KA9FOX@aol.com)
Date: Tue Sep 13 20:03:07 1994
Thanks to the following for their much appreciated input:  AA4GA,
AA6KX/ZF8BS, AB6FO, K0GU, K1KP, KR0Y, KU4J, NU6S, VE4GV, VE6SH, VR2GO, W0CP,
WB0GAZ, WB2K, WB4FLB, WB9TIY, WJ2O, and whoever Glenn mgvinson@crl.com is
(sri OM - no call listed on message).

If I can find one reasonably priced, it looks like the Dentron MLA-2500 amp
is the one to get.  Only bad thing about this amp is the price of replacing
the 8875 tubes.  Hope you find the following comments helpful:

DENTRON MLA-2500--------------------------------
     "I've owned lots of different amps, but I'd have to recommend
a Dentron MLA-2500 if you can find a good one. Why? It fits the bill of a
contester. First off it's 160-10m (no amp on 160 = wimp city). Second it's
full power, not just 600-700w. Third, hefty compact chassis. Not real heavy
considering what it puts out. Fourth, runs of 110 or 220v. Can come in
handy sometimes. Drawbacks...It runs 8875's which are hard to find, but I
ran mine for years without a problem. No tuned input, but I ran it with
rigs that didn't have a auto-tuner and it was fine." -WB2K
     "I bought an MLA 2500 for $425 for my XE trip. With the tubes that came
with it (well worn) it ran 700-800 watts 10-160. New tubes cost more than the
amp, so
that isn't worth it. It isn't pretty, but it is built like a tank and you
can't beat the price. I've seen them advertised on a regular basis in HTYS."
-AB6FO
     "Here's a suggestion--and it's a suggestion only, because I won't part
with mine.  I have a used Dentron MLA-2500B I bought for only $400, and it is
exactly the item for expedition trips.  This thing will handle 160-10 and put
out just about a KW with 100w of drive.  It can be wired for either 110 or
220 very easily.  Most important, it is just small enough to fit under the
seat in front of you on a plane and so qualifies as "carry-on" baggage.  (But
it does take practice to carry  this thing around without showing how much it
weighs!)  This is the same kind of amp Lloyd & Iris used to lug around.  If
you can one for about $500, I'd say it was a fair deal.  P.S. I'll be
dragging this amp down to ZF8 for CQWW-CW" -AA6KX/ZF8BS
     "See if you can find yourself a MLA2500 that still has good tubes.  I
used one of those for 4 straight years in the Carib and racked up close to
100,000 Q's between contests and pre-contest operating.  Never had a problem.
 Damn thing was close to bulletproof.  CAUTION: You don't even WANT to know
how much tubes cost!!" -WB9TIY
     "Most guys I know bring a Dentron. They are smaller, lighter, and less
fragile. But I dont have one." -NU6S
     "Some old Dentron MLA2500 around that are 10-160m but they use EXPENSIVE
ceramic tubes." -KR0Y
     "I've been on several contest trips where we carried MLA2500's.  The
tubes
are expensive, and the power supply caps are sometimes a problem, and 
sometimes they arc....but  they're probably the best watts/dollar/pound
solution." -AA4GA

DENTRON GLA-2500--------------------------------
     "Watch out for the Dentron GLA-1000 series, which is very compact and
inexpensive, but costs lots of $$ to retube." -WB0GAZ
     "You know people will laugh but I have used an old Dentron GLA1000B when
I DXpedited years ago(ZB2 and EA8)-yeah I know it only runs 500W tops but its
easy to fix and the tubes are cheap and easy to find-runs on 120/220 etc.
 Heck they only cost $200-300 down your way." -VE6SH

DENTROL CLIPPERTON-L--------------------------------
     "This maybe out of your price range, but a Clipperton "L" may be the
ticket. These things are tough as nails if you get a good one and it is
painfully simple to deal with. I'm sorry I sold mine (VR2IH has it now)."
-VR2GO
     "Clipperton-L  a good choice (10-160). I had one but sold it. Abt $350."
-KR0Y

HEATHKIT SB-220/200--------------------------------
     "Believe it or not, the SB220 will fit under the seat infront of you. I
usually disconnect the AC cord for travel and attatch a handle.  So far it
has survived KH6, VP2M, P40,  with side trips to V2, KP4, KP2, PJ2 and
numerous trips to other W6 QTH's. It also has never let me down (unlike 2
different Alphas that I used during contests). Just be careful not to break
the 3-500's."-NU6S
     "If you wanted something bigger, but cheap and less power, I guess
and SB220, but that's a hog to haul around." -AA4GA
     "SB-200.  It is light, 110/220v, tolerant of bad antenna matches, and
fits  your budget.  We have used it in 2 rtty contests.  We have also used
bigger and more expensive amps which are very useful but don't fit your
criteria." -mgvinson@crl.com

FL-2100-------------------------------------------
     "In the early eighties I used an fl2100b for short dx trips.  They sell
used now for about $400. Uses a pair of 572B's."-W0CP
     "I suggest an old FL2100 series amp. Relatively cheap, can be hand
carried with appropriate mods for handle."-VE4GV

AMP SUPPLY LA-1000 / LK-500----------------------
     "Stay away from sweep tube amps. The're small but the LA-1000 I borrowed
and carried to 6Y5 land lasted all of 5 qsos."-VE4GV
     "I have an AMP SUPPY LA-1000 that I've taken on several trips. It uses 4
sweep tubes and puts out about 500 watts.  It is small in size and easy to
pack and carry on the trip."-WB4FLB
     "...or an AMP SUPPLY LK-500 type, 10-160 pair of 3-500Z.  Thats what I
have now, about 600 bux."-KR0Y

OTHER AMPLIFIERS--------------------------------
     "We took a 30L1 in its custom travel case with us to ZF8. It provided
plenty
of poop and travelled well, and I think it fits your budget."-K1KP
     "We ended up using Ameritron AL-811A's from VP2VFP. We had the 4 tube
version but with line regulation in the Carribbean you will be lucky to get
the full rate 600w output. I believe it weighs about 35 lbs, there is nothing
else in that weight class next step up is in 50lb - 75 lb range." -KU4J
     "Scott this doesn't really fit your profile but thought I would pass it
along anyway. I travel with my Alpha 76PA. I got the small hypersil for the
76A (1.5KVA). I have a old woodside suitcase that the Alpha fits in
perfectly. I take out the xformer and carry it on in a shoulder bag (gets
interesting looks at the X-ray machine). The 76PA in the suitcase survived a
eight foot fall onto concrete at the Guyana airport. You MUST get a VERY
reliable amp for traveling that can easily be converted to 120 or 220 volts."
-K0GU
     "I take my Yaesu FL7000 on most of my trips, but I hate it and it cost a
lot more than $400 to $500.  It is constantly tripping out it's protection
circuit (antenna currents have to be darn perfect), and I've never got it up
to the 600 watts it's rated for.  Typically run 300 watts out.  Even 300
watts is a hugh improvement over running barefoot.  The good things about
this amp.  Automatic band switching and I can configuring the wiring to
accept many different ac voltage inputs from 110 to 240." -WJ2O

MISCELLANEOUS COMMENTS--------------------------------
     "Some tubes are cheaper and more readily available than others.  Avoid
8874's. Some tubes are probably more rugged during transport than others.
 Avoid 4-1000's, 3-1000's, and maybe 3-500's.  Sweep tubes are getting
expensive. Watch out for the Dentron GLA-1000 series, which is very compact
and inexpensive, but costs lots of $$ to retube." -WB0GAZ
     "Power transformers are _heavy_, and when the amp is in shipment,
bouncing it around could bend the chassis or transformer mounting hardware.
Reinforce the appropriate spots on the chassis, and/or use an external HV
supply."-WB0GAZ
     "Don't believe the hype, run <500w in contests."-W0CP
     "If you are going to running off of generator power....avoid anything on
the new side for they don't like unstable voltages. I keep an Alpha 374 (not
the 374A) in top shape because its old, and it really pumps when being fed by
portable power. Not even a flinch. -- As a rule of thumb....avoid anything
with IC's for portable operation."-VR2GO
     "Bring a good tuner also. I picked up a used Drake MN 2700 that covers
10-160 for about $250."-AB6FO

ABOUT ME TURNING 30--------------------------------
     "Congrats on the BIG 3-0!!! I had mine in June of this year. After
turning 
30 you begin to look at things differently. Don't let it scare you.  Happy
birthday!!!" -VR2GO
     "Happy Birthday Scott, you can now look forward to growing a spare tire,
having your hair fall out, periodontal (gum) surgery, prostate problems,
lack of stamina in contests, and realizing that the babe you just ogled could
be your daughter. (Honestly officer, she looked at LEAST 18) "What a drag it
is getting old " Jagger and Richards 1965.  Oh to be young and stupid!"
-VE4GV (38 kicking and screaming toward the big Four O)
     "Congrats on turning 30, but beware, it is a tough one, at least it was
for me.  40 was easy. Still have a way to go to the big 5 oh.  By the way, is
your babe file for real, or just a spoof?" -AB6FO (Yes, unfortunately the
trials and tribulations of my babe search are very real!! -Scott)
     "You think 30 is bad wait until someone refers to you as middle
aged!!!!!! (Happened two weeks ago at a pub-I'm only 34!)" -VE6SH
     "Your just a kid! I turn 40 tomorrow and all my equipment seems to still
function fine......:-)" - K0GU








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