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Reviews For: ACOM 2000a

Category: Amplifiers: RF Power - HF & HF+6M

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Review Summary For : ACOM 2000a
Reviews: 105MSRP: 6850 USD
Description:
ON4UN demonstrates the ACOM 2000A Automatic HF Linear Amplifier
Product is in production
More Info: http://www.acom-bg.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
251054.9
DL1GLH Rating: 2004-01-20
FB AMP Time Owned: more than 12 months.
Using it for 2 years now. Nice amp, no problems at all.
N5HTY Rating: 2003-10-10
Smooth Operation Time Owned: 0 to 3 months.
I only have 150 hours on the amp but so far it has operated flawlessly. Yuo do not even know it is there. It is like having a 1.5kw transceiver. The remote RCU is nice so you may have the amplifier positioned several feet away from yoour operating position, although the amp is very quite anyway. My Alpha 87a's would fault every once in a while when I would change bands. So far the Acom 2000a has never missed a beat.
LY2TA Rating: 2003-06-25
FB AMP Time Owned: more than 12 months.
Using ACOM 2000A since 1999 February. Nice amp, no problems. After that we buy second and third...
K4HW Rating: 2002-11-07
Can't imagine anything better Time Owned: more than 12 months.
The amp is located on the first floor on a specially made shelf up near the ceiling. This is a pretty inaccesable location but fortunately there has never been a need to open the case since it was first installed over 6000 hours ago. It is feeding a remoted MatchMaster tuner which goes a long way to keeping the reflected power meter dark. The amp is controlled with the RCU in the shack on the third floor. I continue to be very impressed with this piece of equipment.
REMOVED_K3KO Rating: 2002-05-30
@2200 hrs Time Owned: more than 12 months.
Mine arrived fall of 2000 and has 2200 hours on it now. Has been back for repair twice.

1) Two incidents of tube failures
2) Heater connectors.

Been 16 months since last trip to Krassy.

Only complaint is that at the least little power line glitch the unit shuts down. This is quite inconvenient in a contest (earphones on and can't hear the beeps) and in a pile-up.

Some kind of electrical inertia is needed to ride out the small power line voltage dips.

Also, the access for bias adjustments when tubes are installed requires dropping front panel and disabling a lockout. I would not object to two holes in the front panel to get at these controls. Put an ACOM logo over them or something to hide if the purists object.

This amp is impossible to troubleshoot in the usual fashion due to protection circuitry. Something as simple as determining which tube is bad is impossible without a spare to plug in.

No excuse for filiament connector problems!
OH2DK Rating: 2001-12-03
Nice functionality, bad designed Time Owned: more than 12 months.
ACOM 2000a is really a great amplifier when it works. But...After some 1000 QSOs it started to alarm low heater (filament) voltage. It was warranty repaired in a shop recommended by the dealer. The heater voltage was low because the connector was burned - not designed for 3.5A. Others have reported the same problem. Recently the same problem returned again, probably the heater voltage connector to the other tube need to be bypassed.

In between my ACOM stopped working because of detected control grid current leak. There was no real current leak. The opamp of the grid current measuring circuit was oscillating because of illegal opamp biasing (biasing well outside data sheet spec, input outside leagal region). Proper redesign of the circuit would have required a lot of changes - the dangling components would generate a reliability risk. I selected to add a resistor to artificially force the amplifier from the oscillation turned off state to a slightly active state. This stopped the oscillations and eliminated the problem without disturbing the intended functionality of the circuit - verified by thorough testing.

In case of problem, the SW switches the amplifier off without letting you seek for reasons. It also forgets to cool the tubes in those conditions. I would like to redesign the ACOM SW to handle fault conditions reasonably.

I would hesitate to use ACOM as the only linear on an expedition - the risk to get in Jukka's situation on Pitcairn is too high. The concept is good, but design quality is far below what would be expected of a product of this price category.
K6ANP Rating: 2001-07-16
Excellent Amp. Well constructed Time Owned: 6 to 12 months.
It is the best amp I've ever owned. It is very easy to setup and operate. I ordered the 2000S remote switch with it. The combination can't be beat. Changing band and antenna is automatic. Late in the contest when fatique sets in and changing bands while forgetting to switch antenna can happen. The A2000 amp and switch combo removes the potential. Construction and quality is excellent. All critical measurements are monitored and if any are out of limits the amp automatically switches to standby. The best feature is the built in automatic antenna tuner. The second best feature is that the amp sits on the floor away from the top of the operating position. The remote control unit roughly 5"X 6.5" is the only thing that takes up operating space. The amp is very quiet even during contesting the blowers do not increase speed emulating the sound of a 707 during take off.

I would recomend the amp without hesitation.
EA5DFV Rating: 2001-04-12
I'm very happy with it Time Owned: 6 to 12 months.
This is a modern tube amplifier. It tune very fast and with accuracy. I don't need the automatic tune capability in the contest, but in this days, with the packet running fast, it perfoms very well chasing DX.

It is very easy to install and use, and with the remote control unit, you can know any parameter and measurement important in the amplifier.

But, for me, the very very impressive of this amplifier is its support and service: I ask to Acom about the heater light blink by e-mail and have the reply in few hours. Also I have a minor problem with the comunications between the rcu and the amplifier, and Acom send me a lot of test and procedures to fix it, but due to my poor electronic knowledge I need to send the amp to Acom: they only need one and half day to fix it, test it, and return to me.

I use it in the past CQ WW, CQ WPX and EA RTTY contest, and the amplifier works fine, quiet and precise.

The problem for me now is that I like it more that my old Collins 30L-1
PA1KW Rating: 2001-03-08
the best Time Owned: 3 to 6 months.
I have this linear amp now for about 5 months.
I was using a alpha 91 and a tl922 before, this are also great linears, but the Acom is the best i ever had.
It runs very easy 1500 watts out, and you don't now that you are using an amplifier.
It runs cool, you don't hear it at all, and sometimes i forgot to switch it in standby for local qso's
Now problems until now, only sometimes when the mains is low the heater led lights.
Short to say simply the best on the market.
They only forgot to send me the famous christmas card that owners received arround christmas time (hihi)
If you are looking for a new amp, buy it and you will be satisfied.

Bert PA1KW pa1kw@amsat.org
S51TA Rating: 2001-01-16
ACOM is great Time Owned: 0 to 3 months.
I was working with Acom in 1999 at cn8ww. I was amazed and still am. I think ACOM is great amplifier except price! Maybe students should get some special price and WWYC members!
MAybe this would be another good way for getting some youngsters into hamradio!
Once again, great amp but will have to wait few years to have one, pitty!

73 Ted, s51ta, age 21