Call Search

New to Ham Radio?
My Profile

Friends Remembered
Survey Question

DX Cluster Spots

Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement

   Home   Help Search  
Pages: [1]   Go Down
Author Topic: Opinions on ACOM 1000, 1010, & 1011 Amps  (Read 3340 times)

Posts: 109

« on: March 21, 2013, 06:40:41 AM »

I'm considering a new 500 to 1kW amp, and among the tube amps, I'm looking at the ACOM 1000, 1010, or 1011 (listed in descending order of price).  The 1000 and 1010 use a single 4CX800A/GU74B, whereas the 1011 uses a pair of 4CX250Bs.  The 1000 uses a larger transformer than the 1010, has a more rugged build (higher quality components) than either the lesser 1010 and 1011, supports full QSK, and covers 160-6m - whereas the 1010 and 1011 are 160-10m only.

Although the 4XC800A/GU74B has not been discontinued by Svetlana, their production runs are sporadic, and it is becoming more expensive (currently around $300 NOS), as are all tubes of course.  On the the hand, the 4CX250B remains rather plentiful, and certainly less expensive.

What's the general consensus on ACOM's lower-priced (relatively speaking of course) amps, and their long-term reliability.  The amps are sold, and backed, by Array Solutions here in the USA - a very fine and reputable company which offers excellent customer service.

The amp for this application would be used primarily on SSB, as I have another full QSK amp I use on CW.  Although it never hurts to have another full QSK capable amp in the shack...  the price differential between the low-end 1011 and the 1000 is $1,000.

I am also considering a couple of solid-state amps in the 500 to 1kW range.

Any thoughts would be appreciated...

Don W9CW

Posts: 1816

« Reply #1 on: March 21, 2013, 07:42:16 AM »

The 1000 was my at the top on my Dayton shopping list several years back, so my the data which forms my opinion is a few years old.  Nicely made with a great tube.  If you don't abuse it, the GU74B may last for many years. It covers 160-6 meters which is rare.  I was sold.  HOWEVER... I was turned off by the the sales team at Dayton which featured the owner K1LZ and his (at the time) US sales rep. So I moved onto the Emtron booth and received a warm welcome from their US rep and owner Rudi who pulled the covers off their DX1d, an amp which featured the same GU74B tube but which didn't have the 6m option.  That was a negative.  But I liked the sales force was friendly and willing to answers any questions.  The amp was beautifully constructed with a rugged chassis and transformer.  Is it unreasonalble to expect to be treated at least cordially when you've got a roll of $3500 in your pocket to drop on a hobby?  I didn't think so.  I went with the Emtron.

I guess if you buy from a distributor, you won't encounter personalities that make you form a general opinion of the product.  But at the time, neither amp was sold by a retail outlet (Emtron still isn't) so you were forced to seek out the individual that represented them in the US.
« Last Edit: March 21, 2013, 07:46:26 AM by K3GM » Logged

Posts: 3524

« Reply #2 on: March 21, 2013, 10:08:24 AM »

Everybody can have a bad day. Don’t let that color your technical considerations. In my opinion the 160-6 meter amplifier by Acom (1000) is one of the best bargains out there. Six meters is a very desirable band and having to buy only one amp for all the useful HF bands are a plus.

The cost of an amplifier is what it depreciates. ACOM  has a stellar reputation, the amplifier design is mature, many have been made and their resale is very good.

The 4CX800A7 (GU-74B) is very available and is also being made by the Chinese. This tube will be around for a long time.  The key to tube life is not trying to get the last 10% of power out of the tube.

As far as solid state amplifiers go remember they have a hard power output limit. Unlike tubes that go into power compression softly, transistors when they hit the rail voltage are very nonlinear. Also they are not tolerant of VSWR issues and will blow out instantly if the load is less than perfect.  If you use an antenna tuner to resonate the feed to your antenna, I would not use a solid state amplifier. One sleepy oppsey can be expensive.

Posts: 109

« Reply #3 on: March 21, 2013, 10:38:17 AM »

Thanks Mike.  BTW... I enjoyed our dinner together with Molly Hardman at Chili's at the 2010 Huntsville show, and the unscheduled stop at Walgreens on the way back to the hotel to pick up some Aleve Smiley. This, of course, was prior to my retirement from CQ at the end of that year. 

Yes, the ACOM line look like a nice amps, and well engineered with super build quality and well-protected.  Re. solid-state amps and VSWR protection, especially as to its use with an antenna tuner... it appears the Elecraft KPA500 is well-protected against most loads, and other "oops" moments.

Posts: 4719

« Reply #4 on: March 21, 2013, 03:30:04 PM »

I'm serously thinking about an Acom 1500 - one reason being that I have a couple of good 4CX1000 in stock. I've figured that I am now not in good enough health to do the building and the question before buying an amp is what the doctors are going to tell me about life expetency. The pension guys are giving me an 8% return on the pension pot which doesn't bode that well.....

Getting old is a sh*t, especially at 66..............just the alternative is worse.

But the Acom 1500 looks very good......and likely to outlive me.

Posts: 95

« Reply #5 on: March 25, 2013, 03:17:59 PM »

I do not own on of these amps, but I got to operate the 1000 for SS in Nebraska this past year ... both CW and SSB ... as K0S.  The 1000 is superb.  Very quiet.  We were driving it with a K3 and it operated very well.  Ran full power on CW and never had a glitch with it.  Works just as well on SSB. I would love to own one of these gems.

Lee - K0WA

Posts: 72

« Reply #6 on: March 27, 2013, 05:02:41 PM »

Don - I've had and operate an ACOM 1010 basically since they were first available in the U.S. - early 2006.  With a solid distributor like Array Solutions things will only be better.  Even back then, the ACOM distributor was extra friendly and I had direct support from Bulgaria that was top-notch.

I've abused this amplifier!  It's been on a dozen plane rides with me.  The only problem I've ever had was that with all this banging around, and with this early design, I needed to replace and mechanically reinforce a capacitor.  Also, back then there was a popular mod that reduced the fan speed, which was unnecessarily fast.   Neither of these is any issue with new models, no worries - my point is that the factory guided me promptly and flawlessly through the issues.  A++ for responsiveness!

Honestly, the extra few watts to upgrade to an ACOM 1000 are not really an issue for me.  The fully automatic operation really is kind of tempting, though!  However, the tune-up for the 1010 is very easy with well thought-out readouts.  It doesn't have fast inter-character QSK, but the transmit/receive switching is good enough for high speed CW, definitely for SSB.

This amp is, for me, just so second-nature that I can't imagine replacing it.  Bulletproof, easy to use, and just works. 

Mni 73 es gud DX de David AB0Z

Posts: 743

« Reply #7 on: March 30, 2013, 04:42:35 AM »

I have read stories about the finals and that they must be special hand-picked and matched by Acom. The amp or your defective finals have to be sent back to Acom to get it right.
Any truth to that?

Posts: 109

« Reply #8 on: March 30, 2013, 08:05:22 AM »

Well, in the case of the ACOM 1000 and the 1010, there is only one tube - no tubes to match.  The statement in the manual regarding tube replacement, e.g. sending it back to an authorized ACOM dealer, is based upon EU liability laws, not applicable here in the USA.  If the final tube needs replacement, I am sure any technically-inclined ham could do so - with the technical assistance of Array Solutions if necessary.  No truth whatsoever that you would have to send the tube or the amp back to ACOM, or an authorized dealer.  Array Solutions has all of the technical info on tube replacement and can easily "walk you through" the tube replacement scenario if necessary.  Using the amp properly, the GU74B should last a very long time.

Pages: [1]   Go Up
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!