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[Articles Home]  [Add Article]  

Help, I Need a Cheap HF Amplifier II

James Benedict (N8FVJ) on April 16, 2018
View comments about this article!

I wrote an article over 10 tears ago on buying a cheap used HF amplifier. The field has changed and some of the cheap amplifiers are getting quite rare and others are getting more expensive plus may need some components replaced.

The recommended used amplifier list in my original article consisted of the Ameritron AL-811, Gonset GSB-201, Dentron Clipperton L, Hunter Bandit 2000B, over budget Collins 30l-1 & Heathkit HA-14. The Gonset & Hunter is getting rare plus the Hunter Bandit is rather expensive now along with the Heathkit HA-14 compact kilowatt amp.

Another problem is the excellent Cetron 572B is not found often and expensive now. The 811 & 572B tubes from China are not reliable. I know RF parts screens these tubes, but I am hearing some reports of 1500 hours tube life if the tube does not fail earlier due to internal arcing or complete filament failure.

As I said before it is truly no fun trying to talk SSB on 75 meters at night. The band is particularly noisy right now.

In my earlier article the Heathkit SB-200 was my top choice. 10 years ago reasonable cost Cetron 572Bs were available. Now those tubes cost over $200 a pair and getting rare. And, the Heathkit power supplies are really needing a rebuild. Plus cheap SB-200 amplifiers are not found often, This remarkable amplifier has performed well over the years.

If you want the Heathkit SB-200, I have seen it as low as $300. However, $425 to $500 is the average cost. Look for a SB-200 that already has the upgrades such as a new power supply board. The power supply board is old and the capacitors are starting to fail. Make sure the amp outputs 600 watts with 50-70 watts drive. Higher drive to achieve 600 watts indicates tubes that are getting soft. If the tubes are already soft, I would not buy the amp unless it is about $300 and a pair of $200 Cetron 572B are available. The NOS Cetron only show up on eBay every few months.

The Collins 30L-1 is still $600 or higher amplifiers. The Dentron Clipperton L uses four expensive 572B, Replacement tubes can absorb your entire budget.

The only other reasonable cost amplifier left is the Ameritron AL-811 and AL-811H. The AL-811 amplifiers are $400 to $500. The AL-811H that has four tubes and usually costs over $500 with an average of $600-$700 used. But I have seen a few around $500.

The problem with the AL-811 and AL-811H are the tubes. The amplifier itself is reliable despite what others may say. Pay no attention to those ham radio operators. They believe anything less that a $1000 to $4000 amplifier is junk. Hams did not used to be rude braggarts, but some are now. Due to this, I will not comment to replies on this article.

The only saving grace at this moment is the Russian 811A tube. These tubes are not well known. The Russian 811 is called a G811 and are available around $20 each on eBay. Search for G811 on eBay.

Now for the Ameritron AL-811 and AL811H. The output rating is a little exaggerated by the manufacture for long tube life. I would de-rate the AL-811 to 500 watts PEP and the AL-811H 650 watts PEP output. Also, do not tune the 811A tube amplifiers for more than 10 seconds or the tubes may be damaged.

Either way, your signal will be stronger with your new amplifier than your stock radio and at that output good for 90% of successful contacts.

Member Comments:
Add A Comment
 
Help, I Need a Cheap HF Amplifier II Reply
by MM0IMC on April 16, 2018 Mail this to a friend!
There will always be naysayers when it comes to the Ameritron 811 range of amplifiers, but they are a reasonably good first amplifier. The valves (tubes) are relatively easy to source and for the most part, they are easy to work on (except for what's behind the rear panel).
 
Help, I Need a Cheap HF Amplifier II Reply
by W0WCA on April 16, 2018 Mail this to a friend!
Half a dozen years ago I bought an AL-811 for $200. I replaced all three tubes and the parasitic suppressor board for $80 and have been using the amp at will ever since and am quite pleased with it.
 
Help, I Need a Cheap HF Amplifier II Reply
by VK3BL on April 16, 2018 Mail this to a friend!
Nice of you to thank your sources.

100% of your recommendations come from the very 'rude braggarts' you despise.

VK3BL/VK3HXT: Russian G811 is made by Ryazan who "made" the much loved Svetlana 811A.

KM1H et al: The 811H series is really a 500W Amp.

W8JI/Ameritron: Don't tune for more than 10 seconds.

You don't get to call the very people that informed you dicks, and then present the info as your own.
 
Help, I Need a Cheap HF Amplifier II Reply
by VK3BL on April 16, 2018 Mail this to a friend!
Yes, I really did cover the G811 situation and start the modern "revival" of their usage when I noticed the Ryazan logo on both the ebay specials and the Svetlana's.

See my blog post here.

https://vk3bl.wordpress.com/2016/02/11/ryazan-g-811-aka-svetlana-811a/
 
Help, I Need a Cheap HF Amplifier II Reply
by ANDREW30 on April 16, 2018 Mail this to a friend!
"over 10 tears ago".
That must have been, positively, very emotional experience. ;-)
 
Help, I Need a Cheap HF Amplifier II Reply
by AC2RY on April 16, 2018 Mail this to a friend!
Forget tubes. You can find solid state amplifier under $1000. Of cause it will be second hand, But no need to worry about tubes failing, excessive heat etc. We are in 21st century - time to move on to proven solid state technology.
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by K6AER on April 16, 2018 Mail this to a friend!
I am willing to bet the failure rate among solid state amplifiers is almost as high as tube units.

At least most hams can replace a tube.

Solid state amps do not tolerate high VSWR,

IMD on tube amps is much better.

Tube amps are cheaper.

Solid State PCB's are fragile to de-soldering the transistors.

A 2000 watt solid state amp is twice the price of a tube amp.

Solid state amplifiers have no head room.

Other than that they are perfect.
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by G3RZP on April 16, 2018 Mail this to a friend!
Spare transistors are needed for a SS amp. Just look at the number of RF power transistors and RF power transistor manufacturers that have disappeared, leaving the market to rip offs on ebay and the like.
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by W5DXP on April 16, 2018 Mail this to a friend!
> K6AER on April 16, 2018 said: Solid state amps do not tolerate high VSWR,<

My SG-500 is rated to work into a max SWR of 6:1. That's more than 1/2 of the forward power being reflected.
--
73, Cecil, w5dxp.com
 
Define "...CHEAP" Reply
by VE3CUI on April 16, 2018 Mail this to a friend!
OK, so I have a homebrewed linear amplifier that I built here some 25 years ago, or so, that uses 813 tubes...remember those venerable rascals?

I have squirrelled away SCORES of these jugs in my junque box over the years through selected purchases at various local flea markets, Hamfests, etc. --- but I will probably never ever use them in MY lifetime, because these ol' bad boys are just like the Ever Ready Energizer Bunny...

"...They keep going, and going, and going..."

Who needs high-tech kilowatt tubes & soldstate devices, anyway...? The station at the other end of my QSOs doesn't know --- nor CARE --- what active devices I might be using at my station: he just wants to hear me...& I just want to be heard.
 
RE: Define "...CHEAP" Reply
by NO9E on April 16, 2018 Mail this to a friend!
It will be nice to read "Cheap amplifier III" in 10 years.

Probably used Experts for $700 and ALS-600 for $300. SB-220 for $4000 as a museum piece (like 1955 Corvette).
Ignacy, NO9E
 
RE: Define "...CHEAP" Reply
by KB6QXM on April 16, 2018 Mail this to a friend!
If hams in general were not cheap, there would be no excuse for this article.

Instead of talking about old legacy amplifiers and blah blah blah about replacing old and hard to find tubes, how about an article on amplifiers that are new and a good value.

There are a lot of new modern amplifiers that are reliable, have a good factory warranty and do not require you to take out a second mortgage on your house for the purchase.

How about an article like that?

73
 
RE: Define "...CHEAP" Reply
by KC7MF on April 16, 2018 Mail this to a friend!
I am surprised by this article. I am not certain where the OP is coming from.

Let's see:

Are the tubes from China reliable? The author says he is "hearing some reports".... How about this. I run a net a few nights each week. People love to tune up on top of it. I could tune a piano in less time than they take to tune an amp. Chinese tubes are reliable. I have used them and had no problem. Five will get you fifty that when we hear of early tube failure, operator carelessness or inexperience is at the heart of it. RF parts gives a one year warranty on their tubes. The author may have "heard some reports" but that is not evidence. I have some RF parts tubes going strong with no problem at all. So here is a report that they are a good product.

For the majority of operators, the AL-811 is a great amp. It is well built, puts out 600 watts (if your experience is that it puts out less, I am going to make that same bet that you do not understand what to do before you put it into operation. Read your manual. Then tell me what watt meter you are using and how.) The tubes are reliable. They are rated properly. I really don't care what the author would do about "rating" these amplifiers but I would comment that there is essentially no difference between 500 and 600 watts, and that most hams do not know how to determine what their amp is putting out not have the correct equipment to do it.


Then the author said this:

""Hams did not used to be rude braggarts, but some are now. Due to this, I will not comment to replies on this article.""

I do not find those few who question the forwarding of unsupported assertions rude. We should question it. Did this author support any of his assertions about items in production with evidence? Nope. Unless you consider "I have heard reports" as evidence.

I am glad this article came out. It spurs a worthy discussion. My opinion is that there are many good used amps out there. They will require maintenance from time to time.


 
RE: Define "...CHEAP" Reply
by AB4D on April 16, 2018 Mail this to a friend!
The 3-500zg is still king for reliable and affordable RF power amplification applications in amateur radio.

That is what I always recommend to new hams looking for an amplifier, after they tell me they have maximized their antenna system. The AL-80b. Drake L-4B, and SB-220, provide the best value on the used amplifier market.

The 811 amps are training wheel amplifiers, prone to issue, and comparatively short tube life. Their only saving grace is cheap tube cost. However, the small savings buying the cheap 811 amplifier, quickly erodes, after a few tube replacement cycles. When many old L-4B and SB-220's are still using their original tubes, decades later.

J
 
RE: Define "...CHEAP" Reply
by K6AER on April 16, 2018 Mail this to a friend!
The OM-2000+ uses a FU728F Tetrode which is capable of 2.3 KW and cost about $350.00. Array Solutions has a 1 year warranty on the tube.

Can anyone name a transistor supplier that provides a warranty on transistors?
 
RE: Define "...CHEAP" Reply
by K6AER on April 16, 2018 Mail this to a friend!
The OM-2000+ uses a FU728F Tetrode which is capable of 2.3 KW and cost about $350.00. Array Solutions has a 1 year warranty on the tube.

Tubes will be around for a long time. They are by far the cheapest watt for the dollar bargain around.

With the exception of the MRF-150 I would like to know what other transistor, FET or LDMOS that the ham community can depend on for production 10-20 years down the road? The ham population does no buy enough new amplifiers to justify 1 one week production of a specific device. All of your amplifier designs have to tail end on the commercial use of a device. We are at the mercy of commercial designs and when a better device comes along our beloved device is obsolete and our sources dry up.

BTW....RF Can anyone name a transistor supplier that provides a warranty on transistors?
 
RE: Define "...CHEAP" Reply
by K6AER on April 16, 2018 Mail this to a friend!
Interesting it posted while I was typing.
 
RE: Define "...CHEAP" Reply
by K6UJ on April 16, 2018 Mail this to a friend!
Good overview on amps Jim !
You were smart to indicate you would not respond to the comments. The antaganistic nonsense ones like Jarads, VK3BL are evidence of your wisdom. hihi

Bob
K6UJ
 
Help, I Need a Cheap HF Amplifier II Reply
by KM1H on April 16, 2018 Mail this to a friend!
The Russian G811 IS NOT A 811A, it is a 811 plain and simple, compare it against a USA made 811A.and see the 3 U shaped fins added to the anode...as far back as 1947....to increase dissipation. The current Chinese version uses a simple top to bottom tab as a half a**ed dissipation improvement; they still fail trying to run at the levels in the Ameritron manuals which is a big fraud/scam IMO.

The G811 was the tube the Chinese copied and did a pretty poor job as they were easy to kill. Ameritron knew this and so did RFP; other sellers likely didnt know the difference and this article original poster has been in denial for over a year.

If you want a good laugh or a sad shake of the head read all about it on the Amplifier forum on here.
https://www.eham.net/ehamforum/smf/index.php/board,1.0.html

The SB-200, Hunter 2000B, Dentron Clipperton L are all good amps but go back to the 60's and 70's and need TLC by now such as PS board replacements, modern parasitic suppressors, a new fan, etc. There are several mods and web pages that cover old amps; a few are excellent and the rest are pure garbage or need careful cherry picking.

Also remember that all amps of that era were restricted to 1000W CW INPUT and 2000W PEP SSB INPUT by the FCC rules, That translates to about 600W CW and 1200W PEP OUTPUT on SSB without all sorts of audio processing and over drive by the new breed of non technical hams. Toss in no experience with high power vacuum tubes and of course even Cetron tubes will fail but those users are in denial and cant believe it was their fault.
Running those amps in the CW position is as linear as in SSB but output will be about half which takes a lot of strain off the tubes and power transformer. That 3dB less power wont even be noticed at the other end in casual conversations and in reality it is only a half S unit weaker.

All 3 of those amps were built for vacuum tube transmitters/transceivers and could tune into them with no trouble for full output. The SB-200 has a sort of a tuned input but it leaves a lot to be desired for SS exciters. The other two dont even have tuned inputs and a tuner is needed to get rated power on some or all bands...it varies. Some Clipperton L's had a tuned input late in their production life when SS was on the rise, results are as mixed as the SB-200.

My amp related creds are building my first KW amp in 1957 while in HS using mostly WW2 surplus. Next came 4 years in the USN as an ET where I specialized in the high power transmitters.

That was followed by 6 years at National Radio where I was on the NCL-2000 design team and did most of the service work on them since I was familiar/comfortable with HV. Since then Ive serviced most brands and models of tube amps and have converted literally hundreds of some models to 6M and shipped all over the world.

Carl
 
Help, I Need a Cheap HF Amplifier II Reply
by VK3BL on April 16, 2018 Mail this to a friend!
BOB K6UJ,

If you find my post antagonistic, consider how myself and others may feel when they read an article plagiarized by a well known phony who won't even visit the amplifiers section anymore because they have been called out so many times.

This article itself is intended to antagonize those who tried to assist the author by stealing their ideas and presenting them as his own.

If you take the time to read through the various Ameritron AL-811 threads in the amplifiers section, you will easily see where I am coming from.

The credit for this article belongs to Myself (VK3BL), Carl (K1MH), Tom (W8JI) and many others who I have neglected to mention.

Where I'm from, plagiarism is a cardinal sin.

On another note, Carl K1MH is indeed correct that the Russian G811 is not an '811A' in any real sense, just like the Chinese FU-811 isn't either. If you manage to find the official data sheets both are rated at around 45W CCS with no ICAS values given.

The FU-811 & G811 are sold as '811A' tubes to AL-811 owning Amateurs who wouldn't know what a true 811A looked like if they googled it.

Tube life is short, but at least they are cheap and last 70% as long as a true NOS RCA 811A costing 3x as much.
 
Help, I Need a Cheap HF Amplifier II Reply
by K6YE on April 16, 2018 Mail this to a friend!
I have had excellent experiences with amplifiers utilizing 3-500ZG triodes. The Drake L-4B and Heathkit SB-220 are very inexpensive examples and are easy to tune. Note well that I did add Harbach mods to both but the overall price was still low. I also owned a Kenwood TL-922A, that had been modified with 10 meters, but I sold it in error.

Amp Supply had the LK series using 3-500s and are also good choices (cheap to purchase and maintain).

K6AER is spot on regarding pricing, operating, and maintenance of solid state amps. In the end, it is just a matter of personal choice. YMMV.

Good luck.

Semper Fi,

Tommy - K6YE
DX IS and CW RULES
 
RE: Define "...CHEAP" Reply
by AC2RY on April 16, 2018 Mail this to a friend!
People are running Yaesu and ICOM solid state amplifiers for over 20 years and do not experience catastrophic failures. It means that when well designed amplifier is used in proper environment - it just works without need of major repairs.

One day I forgot to connect antenna cable and accidentally transmitted from ACOM600S into 6 feet of coax not connected to anything. And you know what - nothing happened. Amplifier just reported error and switched to standby mode. It worked perfectly well after connection to antenna was restored. Many tube amplifiers will experience flash over which destroys tube and surrounding circuit under the same condition.

 
RE: Help, I Need a Cheap HF Amplifier II Reply
by KJ4DGE on April 17, 2018 Mail this to a friend!
I think HAMs in general are wanting, like most folks a "deal" on equipment. Who doesn't? That being said a tube amp has its place by those who run AM or need the power to be heard while running a net on a daily basis like the Maritime Mobile folks and others. It cuts through the noise under bad conditions, but with propagation being so bad on HF over the past couple years the net we have has relied on Echolink as a backup when conditions are really bad. Most of the time if conditions are good you can make solid contacts just running 100 watts and sometimes much less. Maybe your wanting a cheap amp will be read by the same folks in China that sell cheap HT's and they will make a one that fills the void but I doubt it. Right now they are competing with Japan on the QRP HF market with some gear that seems to be OK. In another 10 years who knows where the hobby will be?
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by ZENKI on April 17, 2018 Mail this to a friend!
The Drake L4B should be on your list. I own 6 that have seen 30 years of contest use. The only thing that I have done to them is put in Vacuum relays and changed the power supply capacitors. They are all switched by vacuum relays and I have 1 tuned for every band. You can pick them up for 500 dollars and 160 meters is very easy to add to this amp.

Highly recommended, and does 1kw all day long. You can even throw in 4-400's into them with all the grids grounded. My 10 meter amp has the original Eimac 3-400zs in it. The only other mod you need to do is either change the blower or add some muffin fans to the top of the fan. The l4b uses a full pressurized socket system and chimneys, you will never melt the filament pins like other fan cooled 3-500 amps. Blind Freddy can fix a L4b.

After this, just build a 3cx3000 amp and be done with it. It should last 100 years without replacing the tube in ham service.

 
Help, I Need a Cheap HF Amplifier II Reply
by KE2TR on April 17, 2018 Mail this to a friend!
Not one ham here said anything about the old Yaesu FT2100B/F, these were the japan built versions of the SB200 amp, a little harder to work on but the F model did have 160. These amp's are still around but as far as modifying and working on the SB200 is king.
 
RE: Define "...CHEAP" Reply
by KE2TR on April 17, 2018 Mail this to a friend!
VK3BL is the ham who is posting video's on YouTube, he is or at least he says he is a Telecommunications Engineer yet he uses an SDR receiver at his station as a spectrum analyzer, WTF? An sdr radio is NOT a calibrated spectrum analyzer in which to measure the IMD of a radio, neither is the band scope on an Icom,Yaesu,Kenwood or Flex radio but some out there do think this. I would not trust this fellows point of view here at all, maybe if he had real RF background it might be different but I think Jarrad's been in the outback way too long, lol....
 
RE: Define "...CHEAP" Reply
by VK3BL on April 17, 2018 Mail this to a friend!
KE2TR - I'm not quite sure I've ever claimed an SDR is equivalent to a lab grade spectrum analyser. It is however a good enough instrument to allow a Ham to setup their station in order to produce the minimum level of interference. All in all, I can't quite understand your objection to that.
 
Help, I Need a Cheap HF Amplifier II Reply
by W8QZ on April 17, 2018 Mail this to a friend!
Only personal experience with an amplifier is with a Clipperton L.
With the non-tuned input (as most of them are), it does NOT make my Flex 5000 happy (was OK with a tube-final exciter); I've inserted a small MFJ tuner in between (for TX only), which solved that, but it adds 3 more knobs to twiddle for a frequency change.

Also, the amp acts unstable on the upper bands 15M - 10M) - which aligns with recommendations by W8JI (it really needs neutralization - a project that awaits attention).

Just recently replaced the PS section, with a kit from Harbach Electronics - went smoothly, and resolved the distorted signal issue I was having (likely due to dried out capacitors & hum).
 
RE: Define "...CHEAP" Reply
by ZENKI on April 17, 2018 Mail this to a friend!
Theres nothing wrong with using an SDR receiver to check 2 tone IMD. You have to ask yourself what instrument do hams have in their shacks that have a 1 or 2db accuracy. Also the better SDr radios like the Perseus have a better dynamic range than most old or cheap spectrum analyzers. Check the specifications of a cheap Rigol they are not much better in terms of accuracy on their Dbm scale. Many of the cheaper spectrum analyzers have bad phase noise performance and many SDR radios have much better phase noise performance.

Then lets talk about speed. Most of the old spectrum analyzers that hams can afford have insufficient dynamic range and speed to actually see and capture low level IMD that still cause interference. They are sweeping instruments that dont always capture low level IMD unless its very bad. SDR receivers can capture these products in a much more reliable fashion especially when using a waterfall.

Its all about understanding the limitations of ham level SDR technology and understanding the limitations of the instrument and your measurement methodology.

Fact is that you can spend 10,000 on a IC7851 or a IC7610 and get a useless uncalibrated s-meter that has 300% inaccuracy. Something like the new SDRplay SDR radios can be calibrated to be very accurate. For the 200 dollars its has much more precision than the over priced ham transceivers that cause a lot of splatter and that have useless s-meters that cant measure much. Its almost an insult telling other hams how many Db difference there is on these expensive radios that cant measure anything.

SDR receivers are useful tools than most ham grade receivers cant match. Its certainly better than a monitor scope for measuring really dynamic SSB imd or splatter.
 
RE: Define "...CHEAP" Reply
by VK3BL on April 17, 2018 Mail this to a friend!
Cheers Zenki.
 
Help, I Need a Cheap HF Amplifier II Reply
by W6CAW on April 17, 2018 Mail this to a friend!
Thanks for the heads up on the G811. I bought a used 811 5 years ago and it is still working great with the Taylor 811H tubes installed.
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by N9AOP on April 17, 2018 Mail this to a friend!
As I remember it, Dentron amps allowed you to meet all your neighbors.
Art
 
Help, I Need a Cheap HF Amplifier II Reply
by KB4MNG on April 17, 2018 Mail this to a friend!
I think today, the best amp on the new/used market is the 3-500z Al 80 b. One can be had under $1K. Good tubes are still being made and will last a life time if treated properly.

I'm sure the 811 is a good amp but just don't like the tube replacement offered.
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by NN2X on April 17, 2018 Mail this to a friend!
I just sold an Emtron Amplifier DX 3SP, with a pair of FU-728F (2 X 4CX1500).

The sale price $3,500 The amplifier can generate 5KW PEP..(I had sell / for my son's private school! Otherwise I would had never sold).


My point is, when you can buy an amplifier, for a dollar a watt is a great price...Anything lower is fantastic!

I had a few AMP, such as QRO 2500DX, SSB 220, SB 200 and Kenwood 922 all very good. All around the dollar / watt price expect for the SB 220 & SB 200..


 
RE: Help, I Need a Cheap HF Amplifier II Reply
by N6JSX on April 18, 2018 Mail this to a friend!
Forgot two more really good amps, Swan-Mk1 and SB-230, both hard to find but work great! I have an AL811 & SB-230 that cruise at 400W.

With as poor as the bands have been for the last decade plus we need that little bit more to be serious. I figure if most DX Countries outlaw Amp usage the best barefoot they have is 200W. (you know I do not ever recall working a DX using a Swan-350/500) If I'm 3dB better it makes the DX comfortable hear me, I'll snag the contact and even have a nice QSO (maybe a strain for me but that's why I have IF DSP).

Pile-ups/contests I just avoid as the USA big guns running +1500W dominate and 100W barefoot pea-shooters and even 500W have minimal luck while the USA big boys continually stomp us into the noise.
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by G3RZP on April 18, 2018 Mail this to a friend!
>>> (you know I do not ever recall working a DX using a Swan-350/500<<<

KW Electronics in the UK pretty well copied the Swan 350, but turned it through 90 degrees so it wasn't so obviously a copy. Sold over a couple of thousand, split between the UK, Canada and other parts of the world.....
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by KE7FD on April 18, 2018 Mail this to a friend!
I consulted the 800 pound gorilla in the room who said it may be time for some guys to put their hard earned cash into a new[er] solid state amplifier instead of pouring more money into some old tube unit that is on its last leg. When I challenged him saying that some of us are die hard fixer-uppers when it comes to keeping stuff going, he simply asked me if money grew on trees? My retort to him was that something "new" would cost an arm and a leg (after all, some of us would rather duct tape our rusty cars together than buy something we don't have to worry about). He just replied that the purchase of a solid state amp would be more than less, a one time purchase, and not a continual hunt for vacuum tubes from the nether regions of the world.

I don't know if I trust his judgement, he's just a monkey after all, who by the way ridicules anyone who doesn't think like him. I refused to argue with him any longer and went outside to hitch up my wagon to the team to fetch a sack of sugar to make some sarsaparilla for the hoedown tomorrow night.

-.-
 
Help, I Need a Cheap HF Amplifier II Reply
by KM1H on April 18, 2018 Mail this to a friend!
The Russian G811 IS NOT A 811A, it is a 811 plain and simple, compare it against a USA made 811A.and see the 3 U shaped fins added to the anode...as far back as 1947....to increase dissipation. The current Chinese version uses a simple top to bottom tab as a half a**ed dissipation improvement; they still fail trying to run at the levels in the Ameritron manuals which is a big fraud/scam IMO.

The G811 was the tube the Chinese copied and did a pretty poor job as they were easy to kill. Ameritron knew this and so did RFP; other sellers likely didnt know the difference and this article original poster has been in denial for over a year.

If you want a good laugh or a sad shake of the head read all about it on the Amplifier forum on here.
https://www.eham.net/ehamforum/smf/index.php/board,1.0.html

The SB-200, Hunter 2000B, Dentron Clipperton L are all good amps but go back to the 60's and 70's and need TLC by now such as PS board replacements, modern parasitic suppressors, a new fan, etc. There are several mods and web pages that cover old amps; a few are excellent and the rest are pure garbage or need careful cherry picking.

Also remember that all amps of that era were restricted to 1000W CW INPUT and 2000W PEP SSB INPUT by the FCC rules, That translates to about 600W CW and 1200W PEP OUTPUT on SSB without all sorts of audio processing and over drive by the new breed of non technical hams. Toss in no experience with high power vacuum tubes and of course even Cetron tubes will fail but those users are in denial and cant believe it was their fault.
Running those amps in the CW position is as linear as in SSB but output will be about half which takes a lot of strain off the tubes and power transformer. That 3dB less power wont even be noticed at the other end in casual conversations and in reality it is only a half S unit weaker.

All 3 of those amps were built for vacuum tube transmitters/transceivers and could tune into them with no trouble for full output. The SB-200 has a sort of a tuned input but it leaves a lot to be desired for SS exciters. The other two dont even have tuned inputs and a tuner is needed to get rated power on some or all bands...it varies. Some Clipperton L's had a tuned input late in their production life when SS was on the rise, results are as mixed as the SB-200.

My amp related creds are building my first KW amp in 1957 while in HS using mostly WW2 surplus. Next came 4 years in the USN as an ET where I specialized in the high power transmitters.

That was followed by 6 years at National Radio where I was on the NCL-2000 design team and did most of the service work on them since I was familiar/comfortable with HV. Since then Ive serviced most brands and models of tube amps and have converted literally hundreds of some models to 6M and shipped all over the world.

Carl
 
Help, I Need a Cheap HF Amplifier II Reply
by KM1H on April 18, 2018 Mail this to a friend!
The Russian G811 IS NOT A 811A, it is a 811 plain and simple, compare it against a USA made 811A.and see the 3 U shaped fins added to the anode...as far back as 1947....to increase dissipation. The current Chinese version uses a simple top to bottom tab as a half a**ed dissipation improvement; they still fail trying to run at the levels in the Ameritron manuals which is a big fraud/scam IMO.

The G811 was the tube the Chinese copied and did a pretty poor job as they were easy to kill. Ameritron knew this and so did RFP; other sellers likely didnt know the difference and this article original poster has been in denial for over a year.

If you want a good laugh or a sad shake of the head read all about it on the Amplifier forum on here.
https://www.eham.net/ehamforum/smf/index.php/board,1.0.html

The SB-200, Hunter 2000B, Dentron Clipperton L are all good amps but go back to the 60's and 70's and need TLC by now such as PS board replacements, modern parasitic suppressors, a new fan, etc. There are several mods and web pages that cover old amps; a few are excellent and the rest are pure garbage or need careful cherry picking.

Also remember that all amps of that era were restricted to 1000W CW INPUT and 2000W PEP SSB INPUT by the FCC rules, That translates to about 600W CW and 1200W PEP OUTPUT on SSB without all sorts of audio processing and over drive by the new breed of non technical hams. Toss in no experience with high power vacuum tubes and of course even Cetron tubes will fail but those users are in denial and cant believe it was their fault.
Running those amps in the CW position is as linear as in SSB but output will be about half which takes a lot of strain off the tubes and power transformer. That 3dB less power wont even be noticed at the other end in casual conversations and in reality it is only a half S unit weaker.

All 3 of those amps were built for vacuum tube transmitters/transceivers and could tune into them with no trouble for full output. The SB-200 has a sort of a tuned input but it leaves a lot to be desired for SS exciters. The other two dont even have tuned inputs and a tuner is needed to get rated power on some or all bands...it varies. Some Clipperton L's had a tuned input late in their production life when SS was on the rise, results are as mixed as the SB-200.

My amp related creds are building my first KW amp in 1957 while in HS using mostly WW2 surplus. Next came 4 years in the USN as an ET where I specialized in the high power transmitters.

That was followed by 6 years at National Radio where I was on the NCL-2000 design team and did most of the service work on them since I was familiar/comfortable with HV. Since then Ive serviced most brands and models of tube amps and have converted literally hundreds of some models to 6M and shipped all over the world.

Carl
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by KM1H on April 18, 2018 Mail this to a friend!
How do I delete the dupe??

 
RE: Help, I Need a Cheap HF Amplifier II Reply
by VK3BL on April 18, 2018 Mail this to a friend!
You don't Carl.

Never hurts to say things a few times ;)
 
Help, I Need a Cheap HF Amplifier II Reply
by W5GNB on April 19, 2018 Mail this to a friend!
I have Several Amps, an SB-200, SB-220, Ameritron 811H, and an Alpha 99S. All these amps perform flawlessly with cheap tubes, except for the Alpha, it uses the 4cX800's and are quite expensive. The secret is to NOT push the amp to the limits of its power output, run them a bit soft. In the end, you get what you pay for. If you buy a cheap amp and cheap tubes, and you push the limits, you will get limited performance and a short life from the amplifier.
 
Cheap HF Amplifier III Reply
by WD9IDV on April 19, 2018 Mail this to a friend!
My personal favorite is the SunairT-10000B 10 KILOWATT HIGH POWER TRANSMITTER SYSTEM. Easily deployable and capable of STANAG 4444 Frequency Hopping.
 
RE: Cheap HF Amplifier III Reply
by N9AOP on April 19, 2018 Mail this to a friend!
I was all set to get one of those but I don't have 3 phase AC in the shack.
Art
 
RE: Cheap HF Amplifier III Reply
by WD9IDV on April 19, 2018 Mail this to a friend!
"I was all set to get one of those but I don't have 3 phase AC in the shack."

Arthur,

3 phase should not be an issue. Other options exist, like being able to plug directly to your Tesla car.
Or use the hamster wheel generator option to supply power. (3 hamsters required, but not supplied).
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by KM1H on April 19, 2018 Mail this to a friend!
"Amp Supply had the LK series using 3-500s and are also good choices (cheap to purchase and maintain)."

Ive had a LK-500ZC since new in 1986 when I received it as partial payment for consulting work. Even after a decade plus of extremely heavy contest use by the op KQ2M, and heavy DXing by myself and later as an AM linear the original Eimacs still run 1200W which is where I always ran it with reduced drive. The TS-940 IMD was much better plus the tubes werent driven into compression.

Mine had the QSK option as well as the PAC-5 external power transformer (standard on the LK-550)and I added a 2 speed fan switch.

The only failure was a small 'lytic and a relay on the QSK board plus one of the reduction drives. New filters and parasitic suppressor resistors were a PM measure only. The plate choke was replaced by the Ameritron version.

Carl
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by KM1H on April 19, 2018 Mail this to a friend!
"Not one ham here said anything about the old Yaesu FT2100B/F, these were the japan built versions of the SB200 amp, a little harder to work on but the F model did have 160. These amp's are still around but as far as modifying and working on the SB200 is king."

Probably since it is not high on any list at least in the US. Squirrely on 10/12 due to a halfassed neutralization circuit, poor layout leading to instability, clunky relays resulting in hot switching, and insufficient bias cut off voltage for many import tubes.

Ive converted over 100 to 6M monobanders and fixed the problems.

Carl
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by K1ZJH on April 19, 2018 Mail this to a friend!
It is odd that out of those choices he'd mention a HA-14 and ignore the SB 200, which has always been a proven workhorse. And no accolades for the FT-2100? This person has very little real world exposure to reasonably priced VIABLE, reliable, inexpensive vintage amps. And no mention of which lacked tuned cathode input matching?
 
Help, I Need a Cheap HF Amplifier II Reply
by N6KP on April 19, 2018 Mail this to a friend!
Thanks for the good article.
.RE the SB-200 I restored many of them since I was part of the Heath design team back in the 60's.
I think RF Parts had a company in China redo the 572B tubes recently. Once you did the Harbach mods, you have a perfectly good amp.
The HA-14 was just the SB-200 set on it's side. Made a great car heater in the Michigan winters. Could set off a corona ball 2 inches when the weather was damp!

If you can find a clean SB-220 or 221, many are still using the same tubes. I still have several and when the PW-1 dies will put them back on the table.

Ted, N6KP
 
RE: Help, I Need a Cheap HF Amplifier II Reply
by NN2X on April 19, 2018 Mail this to a friend!
I saw on a early comment on this post for a 10KW amplifier (SunairT-10000B 10 KILOWATT)

There is a Emtron Amplifier DX 4 or 5 (A pair of 4CX 2500) generating 10K WATTS for $6K or $7K...

I believe that is cheaper than SunairT-10000B 10 KILOWATT

Cheers

NN2X
 
Some Good Amps Can Be Had Cheap Reply
by W8ASA on April 20, 2018 Mail this to a friend!
A friend of mine in Dayton Ohio is selling a couple of amps:

Drake L4B in very nice condition @ $900.00
Henry 2K4 in very nice condition @ $1,400.00

Both are respected amps. You don't have to spend $3-4K to get a reliable amplifier.

Ken W8ASA
 
RE: Some Good Amps Can Be Had Cheap Reply
by KD0ZGW on April 23, 2018 Mail this to a friend!
I am a relatively new ham. (1st licensed Feb 2014). After about a year I bought a like new AL811H at a swap meet for $500. Used it for about 650 watts SSB. It immediately made a huge difference for me getting heard working DX as my QTH is low noise.

Several months after I bought it during a contest I made an operator mistake and damaged it. Got help, repaired it, and sold it for what I paid.

Learning from the experience, my 2nd amp is an ALS-600 with the interface module for auto band switching. I bought it 2 years ago on swap.qth.com for about $900. It's very forgiving and gives me about 600w. SSB. I made this change because I'm an excitable type that would've certainly made a repeat mistake with the tube amp.

Very rarely do I wish I had more power when working DX. Once my 80/160 antennas are complete I will add a 1500w. amp for those bands.

I offer this because with all the back and forth about models, reliability, tube vs. SS, and actual radiated power this thread would be very confusing for a rookie which I was not so long ago.

IMHO, after a little research, for less than $1000 a ham can get a nice, reliable, moderately powerful amp that will make a noticeable difference in his ability to make contacts. Excitable types should spend the money up front for an amp that is a lot more forgiving than a simple tube amp like the AL811.

My 2 cents.
 
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