Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
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
About eHam.net

donate to eham
   Home   Help Search  
Pages: Prev 1 [2] 3 4 5 6 7 8 Next   Go Down
  Print  
Author Topic: Looking for Linear Amplifier  (Read 31156 times)
K2GWK
Member

Posts: 707


WWW

Ignore
« Reply #15 on: July 24, 2017, 07:01:28 AM »

Never thought about power requirements. I can operate the Acom 1200S on my existing 120 volt line plus other station items. I am ordering the Acom 1200S as soon as the FCC approves. Looks like late summer to early fall of this year. Thanks all.

Don't hold your breath. The Acom 1200S was announced almost 2 years ago.
Logged

Guy
Lawn Guyland, New York

K2GWK Website
K7JQ
Member

Posts: 1316




Ignore
« Reply #16 on: July 24, 2017, 05:37:09 PM »

Never thought about power requirements. I can operate the Acom 1200S on my existing 120 volt line plus other station items. I am ordering the Acom 1200S as soon as the FCC approves. Looks like late summer to early fall of this year. Thanks all.

Anything Acom is quality. However, unless your antenna(s) are resonant across the bands at 1.8:1 or less, be prepared to shell out big bucks for a high power tuner. The amp by itself (no price released yet) might take you over your $4,000 limit, plus the tuner purchase. Again, I caution you running it at 120V, on the same circuit as the other items in the shack. Every time you key down at full power, the lights will dim, or worse.
Logged
W8JX
Member

Posts: 13268




Ignore
« Reply #17 on: July 24, 2017, 06:23:12 PM »

Again, I caution you running it at 120V, on the same circuit as the other items in the shack. Every time you key down at full power, the lights will dim, or worse.

Myself I would not run much over 600 watts or so on 120 even on a separate circuit. Voltage is far more stable on 240.

 
Logged

--------------------------------------
Ham since 1969....  Old School 20wpm REAL Extra Class..
KE4XJ
Member

Posts: 147




Ignore
« Reply #18 on: July 24, 2017, 11:13:43 PM »

As far as the 3- 500ZG goes, my Al-82, with two 3-500 ZG tubes, requires about 65-75 watts drive for 1500 watts out, measured with an Array Solutions Power Master II. I don't know where you heard that you need 150 watts drive in for full legal output.

 I wish I had known of the impending introduction of the OM Power 2000+ when I was shopping for amplifiers. They make very good equipment. I have heard nothing but good things about them. I have been very satisfied with my AL-82, but it does not operate on 50 mHz. My dealings with Array Solutions, who are the U.S. sales source for OM Power amps, have been great.

If you are going to run much more than about 800 watts out, you really need to use a 240 volt circuit for your amp's power. And the 800 watt amp could be the only thing on that 120 volt circuit - and this is really pushing the limits of the safety/dependability envelope .

Brad
KE4XJ
Logged
N3DT
Member

Posts: 1793




Ignore
« Reply #19 on: July 25, 2017, 06:11:11 AM »

Surprised no one has mentioned the AL80B, but it's not the tubes the OP mentioned, but it does put out a solid 800W with 70W in. Usually won't need to go to higher power coax, it comes with a lot of options from Grid Protection to QSK. I've been very happy with my used one I got for $900. A new one all set up may cost something over $2000. Very easy to operate and the tube is much more forgiving than any SS. It's not a quality amp, but they work perfectly fine. Then you can spend another $2000 on antennas or an LP100A.
Logged
K4RVN
Member

Posts: 261




Ignore
« Reply #20 on: July 25, 2017, 07:48:57 AM »

James,
3CX800A7 matched pair of Taylor tubes made in China are less than 900 a pair from RF Parts. Pentas are somewhere around 450 each coming soon. Eimacs are 1495 each.
The Ameritron AL 800H is a nice amp the size of an AL 80B desktop. It has a 3 minute warm up for the tubes, also grid trip out and overload protection. The amp also has a transformer trip out for overload protection I think.  The amp sells new for  about 3845 .
I bought mine used and enjoy it very much. It takes about 50 watts drive for 1200 watts out. I have used 60 watts drive briefly for 1500 watts out. My 3CX 800 A7 tubes are 5 years old with full output. I am using my AL 800H on 40 meters at 1200 watts with 50 watts drive. Tubes should last a very long time with all the protection provided in the AL 800H. The blower noise is not a problem in my opinion even with forced air cooling of the tubes. The amp does not put out a lot of heat. 1500 watts out is not hard on the AL 800H.
I replaced an AL 80B and use the same 240 volt plug in that served the AL80B. I subscribe to what JX wrote about using 220- 240 volts for amps in this power range. My supply here is 240 volts fused @ 20 amps.

Frank
« Last Edit: July 25, 2017, 08:00:08 AM by K4RVN » Logged
W8JX
Member

Posts: 13268




Ignore
« Reply #21 on: July 25, 2017, 08:46:11 AM »

Given that single tube AL800 is rated at 1200 watts PEP little is gained with 2 tube model as same chassis, switched and power supply is used in both. Also, ceramic power tube life is more function of actually burn time or filament lit time as emissions from cathode decrease with burn time at same rate idle or full load as long as it is operated within acceptable limits for tubes. That being said, two tubes will not last twice as long as a single tube. They would last same amount of time and you will need to replace two when times comes vs one with single tube version.
Logged

--------------------------------------
Ham since 1969....  Old School 20wpm REAL Extra Class..
K4RVN
Member

Posts: 261




Ignore
« Reply #22 on: July 25, 2017, 09:01:29 PM »

The 800 amp 3CX800A7 is rated to run 1250 SSB watts by Ameritron. I am running the 800H 1200 watts with two so the amp is loafing. James,  I can't say that running 1200 now or 900 on the AL 80B is enough difference to write home about. The difference is plenty of headroom and the 800H will do over 1500 watts if one is not careful. I really like the 800H after owning 4 amps plus building one years back. The extra 300 watts seem to help on long haul contacts. I'll crank it up to 1500 after I get the feel of it. I only had the amp about 6 weeks now so taking it easy. I would suggest that you get a full legal limit amp if you can afford it now, not later.
I was glad to see RF Parts had spares but doubt if I will ever need them as this one has the Eimacs only 5 years old and not abused.
Having the same transformer in a one tube or more amp is not a negative as long as the voltage required is the same and the additional current capacity is provided in the same transformer. At least that's my experience.

Frank
Logged
W8JX
Member

Posts: 13268




Ignore
« Reply #23 on: July 26, 2017, 07:47:32 AM »

The 800 amp 3CX800A7 is rated to run 1250 SSB watts by Ameritron. I am running the 800H 1200 watts with two so the amp is loafing.

It is not really "loafing: anymore that with one tube at 1200 out. It has same power supply and a 3cx800 does not last any longer "loafing" or a full output, which many do not understand about ceramic power tubes, if properly cooled and since even same cooling fan is used in both models the single tube is well cooled.
Logged

--------------------------------------
Ham since 1969....  Old School 20wpm REAL Extra Class..
KC4ZGP
Member

Posts: 1961




Ignore
« Reply #24 on: July 26, 2017, 09:02:48 AM »


Don't you mean the 2100?

I have been beating myself up looking for the 1200.

Kraus
Logged
K4RVN
Member

Posts: 261




Ignore
« Reply #25 on: July 26, 2017, 04:28:07 PM »


Hey John your cup appears to be half empty while mine is half full. That's OK with me. This is my first experience with ceramic tubes
but have not read one thing about early failure on these. I don't have any experience with the 3CX800A7 but starting now to use them. I don't know squat about ceramic tubes. As for the cooling, it runs really cool and there is a mod. that lets you reduce the cooling on SSB because the article reads the 800H is overcooled for SSB and noisy. Have you seen that? I am hard of hearing so what noise?
http://hamradiomarket.com/articles/quieting%20the%20blower.htm

W8JI, Tom,  hit a home run on this amp in my opinion, and it sure puts out the watts without straining.  I really like this amp
and looking forward to using it for the years I have left.

James I would suggest that you have or install yourself a 220/240 dedicated circuit for 20 amps and quit looking for a legal limit or other amp that will run on 110/120 volts. The amp will thank you for it and you will be happy down the log book. AS for the amps made in China, I still remember the Yugo autos sold by our Ford dealer. With relations becoming more negative due to sanctions and other problems I would sure consider another amp of the same quality made elsewhere.

Frank











h
« Last Edit: July 26, 2017, 04:39:16 PM by K4RVN » Logged
KM1H
Member

Posts: 5559




Ignore
« Reply #26 on: July 26, 2017, 05:52:19 PM »

Ameritron has too many amps that are mostly cut and paste copies of each other and no one model is a big seller beside the AL-80 and AL-811 family.

The AL-800/800H is mostly an Alpha clone using many common parts from other Ameritron amps.

IMO the AL-1500 with the Chinese 8877 is the best $$/performance value of the litter.

Carl
Logged
KC4ZGP
Member

Posts: 1961




Ignore
« Reply #27 on: July 26, 2017, 06:28:34 PM »


Say Carl,

I noticed that too. Why doesn't Ameritron just produce two quality amplifiers instead of

ten mediocre amplifiers. Low power/high power or tube or solid state.

Andy Rooney asked the same of the car manufacturers-just produce a quality car.

Kraus



Logged
K6BRN
Member

Posts: 1354




Ignore
« Reply #28 on: July 26, 2017, 10:18:11 PM »

James (N8FVJ):

Repeating earlier comments by K7JQ and W8JX and hearing that you have $4K to spend, if you are going to run over 600 watts out from an amplifier, plus run all of your other station gear from the same 20A 120V outlet, you'd be very wise to spend $200 and get an electrician to run a dedicated 220V line to your "shack" and run the amplifier off of that.

Otherwise you should limit amplifier output power to about 600 or so watts.

Why?

Well, 1200 watts out of the amp means about 2200 watts AC in (give or take) plus you will likely need about 200-300 watts to power your exciter at full bore (depending on 12V power supply efficiency), plus whatever computer you are running (maybe 100-200 watts) and then maybe you have a rotator, lights and other radios to power - cal it another 100-200 watts.  That adds up to about 2900 watts, or about 24 amps at 120v.  Not a good place to be.  And even counting on low duty cycle transmit time and minimizing other power demands, you will have little power margin.

Put in 220V.  Do it right.

Brian - K6BRN
Logged
K4RVN
Member

Posts: 261




Ignore
« Reply #29 on: July 27, 2017, 08:03:55 AM »

Kraus,
By definition, Mediocre means of moderate or low quality, value, ability, or performance :  I have found my four owned Ameritrons good performers, good values, and the ability to get all continents, US counties and the Grid squares without even trying. Have you ever owned an Ameritron? I think you went a little heavy on Ameritron, and Ameritron owners calling our amps mediocre.  I suspect that unlike Carl you don't know enough to document what you posted. Ameritron and MFJ allows many of us to enjoy the hobby at a reasonable cost, and I for one appreciate their amps. My 28 year old AL80A is still going strong and used most every day. I don't
accept that as mediocre. I posted this so the original topic poster doesn't have to believe that Ameritron amps are not a good value.
I own two at present and enjoy both as good bangs for the buck with parts available and technical support plus repair service.
I'm done now on this subject, no offense intended just a qualified opinion.

Frank
Logged
Pages: Prev 1 [2] 3 4 5 6 7 8 Next   Go Up
  Print  
 
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!