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Author Topic: ALPHA RF SYSTEMS  (Read 1235 times)

AE0Q

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Re: ALPHA RF SYSTEMS
« Reply #15 on: February 24, 2023, 08:36:44 PM »

Although they're all "brick-on-the-key", I don't think I'm gonna' do that with my Alpha 78 at 1500 watts, with 39 year old 8874's...

I sure hope not...  Don't forget that the brick on the key ad with the 78 was "legal Limit" of the day, 1000w DC INPUT power.   That's maybe 700w output :-)  Just keep a little reality here...   The 78 was never built to be a 1500w OUTPUT amp!

Glenn AE0Q
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KA4WJA

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Re: ALPHA RF SYSTEMS
« Reply #16 on: February 24, 2023, 09:44:37 PM »

Yes, Glenn, I'm aware the old Alpha 78 not a 1500 watt output "brick-on-the-key" amp.  :)
(sorry if I implied otherwise)
But, it was designed to output a lot more than 700 watts in SSB service!

Regarding its DC Input Power rating...Directly from the manual:
Quote
The ALPHA 78 is a self - contained , high frequency linear power amplifier capable of
continuous operation at input powers in excess of two kilowatts PEP/SSB and one
kilowatt average or continuous carrier, with no time limit .


Right in the manual, it states its max DC Input Power as 2.5kw CCS...PEP in SSB service.
Quote
Power Input : To 2. 5 kW PEP/SSB, 1 kW average or carrier, dc, CCS
Which of course would pegs the plate current meter on a constant single-tone or carrier...but as the plate current metering is only "average reading", it's way too slow to read any peak values in normal SSB Speech operations.
And btw, this does provide 1500+watts PEP output in SSB service....of course this is not brick-on-the-key carrier! 

And, since the big Hypersil transformer (2.4kva CCS, yes?) provides > > 2kw of DC input, and along with the 1200 watts of dissipation from those three, very linear, 8874's, the Alpha 78 is certainly capable of providing a wicked-clean output of ~ 1500 watts PEP in SSB service, CCS, with no time limit...with only ~ 30 - 35ma of peak Grid Current on old (original?) Eimac 8874's!





Heck, even though it was designed back in the days of "1kw DC input power" regs, the 78's manual even makes sure the operator knew this (when discussing the plate current metering, under SSB tune-up and operation):
Quote
The actual peak or envelope-crest value of plate current under these conditions may range from roughly 0.9 to 1.5 A, depends on such factors as microphone and operator voice characteristics, the exciter ALC system (if any), and the use of speech processing.
The actual PEP (peak envelope power) plate input might range from 2100 x
(0.9 to 1.5) = (1890 to 3150 W)-. .. all the way from about 1.9 kW to over 3 kW in
extreme cases. The average case will approximate 2 to 2.5 kW PEP at 1kW average
input ... roughly equivalent to the "rule of thumb" 2 kW PEP which is often-(mistakenly) referred to as "maximum legal power."
Yep, this is a direct quote from the manual, and no those are not typos....


So, since I've not only used the 78 well for a year or two, I've also done 2-tone testing (at 1650w PEP out, ~ 825w average) and found it very clean...I feel confident saying the Alpha 78 is a beautiful 1250 - 1500 watt PEP output amp, CCS / no-time-limit, in SSB service.
{oh, and those beautiful 8874's are certainly more rugged than their newer/bigger brother, the 3cx800's.....a triplet of 8874's (with 1200w plate diss) have 15 watts of Grid diss, total....versus a pair of 3cx800's (with 1600w plate diss) having only 8 watts of Grid diss, total....just wish they weren't so expensive....last year I paid ~ $425 each, for NOS 8874's...ouch! but now I've got plenty of spares...}


I know this was a bit of a long post....I started with just "yes, Glenn, I'm aware"....and, well....well, I just kinda' got on a roll.  Sorry about that.

Anyway Glenn, thanks for doing what you can with Alpha!  :)

73,
John,  KA4WJA
« Last Edit: February 24, 2023, 10:00:34 PM by KA4WJA »
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AE0Q

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Re: ALPHA RF SYSTEMS
« Reply #17 on: February 24, 2023, 11:33:01 PM »

Yes, Glenn, I'm aware the old Alpha 78 not a 1500 watt output "brick-on-the-key" amp.  :)
(sorry if I implied otherwise)
But, it was designed to output a lot more than 700 watts in SSB service!

SSB isn't brick on the key, that would be CW, yes ?  That's all I said...

Maybe I got spoiled picking up 8410 transformers every day, but that little 78/76A transformer isn't the same as a REAL 1500w, key down, transformer :-)

Glenn AE0Q
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KA4WJA

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Re: ALPHA RF SYSTEMS
« Reply #18 on: February 24, 2023, 11:37:33 PM »

No worries here, Glenn.  :)

I think we are in agreement.

73,
John,  KA4WJA

P.S.  Sorry about my ramble above....a bad week here.  :(
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KA4DPO

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Re: ALPHA RF SYSTEMS
« Reply #19 on: March 01, 2023, 09:34:43 AM »

Does anyone know the status of the new Alpha RF Systems that moved from Colorado to Ohio?  There is a Youtube video on July 11, 2022 taken at Hamvention 2022 where the new owner, Mike Dishop, presented all the new Alpha Products.  In fact, he said presently they have 100 Alpha 9500's under assembly.  The other new products will take a while since they are still having a problem getting parts.  Alpha does not show a phone number on their website, only 2 email addresses.  My email to both has remained unanswered.  Does anyone know if they are in fact open for business at the new location and providing sales, parts and service there?   Thanks, Joe - N1VJJ 

I am the one answering all the Service email at Alpha, I'm in Colorado.  I just tested the email listed on the web site and it is working, but we haven't gotten anything from you.  I answer Service email every day and have already corresponded with an Alpha owner in Japan today.

Mike Dishop answers the Sales email, he is pretty busy at the plant in Ohio where all the Alpha physical things are located now.  If you have questions about ordering products, email him but it might take a day or two for him to answer.  I can help with repair information or anything related to servicing Alpha amps.

Glenn AE0Q

Glenn, since you are the guy who answers the mail on service, is Alpha presently repairing any amplifiers? 

Looks like they moved everything to Ohio some time ago, seems like they should be up and running by now.
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AE0Q

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Re: ALPHA RF SYSTEMS
« Reply #20 on: March 01, 2023, 12:31:21 PM »

Glenn, since you are the guy who answers the mail on service, is Alpha presently repairing any amplifiers? 

Looks like they moved everything to Ohio some time ago, seems like they should be up and running by now.
There is a tech working with Mike and they are taking amps for repairs.

Why do you ask, did you break your Alpha amp working 3Y0J ?
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KA4DPO

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Re: ALPHA RF SYSTEMS
« Reply #21 on: March 14, 2023, 02:30:02 PM »

Glenn, since you are the guy who answers the mail on service, is Alpha presently repairing any amplifiers? 

Looks like they moved everything to Ohio some time ago, seems like they should be up and running by now.
There is a tech working with Mike and they are taking amps for repairs.

Why do you ask, did you break your Alpha amp working 3Y0J ?

No, but I did inavertently put a brick on the key. ;D
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KA4DPO

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Re: ALPHA RF SYSTEMS
« Reply #22 on: March 15, 2023, 12:49:06 PM »

Glenn, since you are the guy who answers the mail on service, is Alpha presently repairing any amplifiers? 

Looks like they moved everything to Ohio some time ago, seems like they should be up and running by now.
There is a tech working with Mike and they are taking amps for repairs.

Why do you ask, did you break your Alpha amp working 3Y0J ?

If you go to the Alpha website, it says they are not taking on any repairs at this time.

https://www.alpharfsystems.com/?page_id=1519

I assume you still have a stake in the company.  If so, you may want to update the webpage to reflect more recent conditions.  You have to admit that almost the entire site for Alpha RF Systems is way out of date. 

I'm still waiting to hear what happened to Emtron.
« Last Edit: March 15, 2023, 12:51:42 PM by KA4DPO »
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KA4DPO

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Re: ALPHA RF SYSTEMS
« Reply #23 on: March 21, 2023, 10:42:55 AM »


"This is a reply to K9HZ that Mike Dishop N8WFF has asked me to post

-----------------------------------------
"If you want support and hand holding then BUY A NEW AMPLIFIER.  Every Alpha comes with a four year warranty except for the tube.  That’s 2200  dollars a year for the peace of mind that you have my support.  At the end of the four years, sell it for 75% of the value and order another new one and you will have four more years of warranty and support."

Steven M. Dishop"

If this is in fact his business model then Alpha may be in trouble.  IMO few hams will cough up $7-8.8+K every 4 yrs for a expensive new amp.   Alpha's customer base was built on their amps robustness and support for a long-life.   He thinks ham's are gonna buy a new $8K amp every 4 yrs and resell the old one for 75% of new??
The used tube amp market is already depressed and likely to worsen.  Especially with no Alpha support for legacy models.

NA4M

I didn't pick up on this post first time around.  The notion that you could sell a used amp for 75% of it's initial cost is pretty wishful thinking, even with inflation.  As far as hand holding service, I had to laugh at that one since the store page paints a pretty bleak picture as far as service goes.

 But if they are serious, then I would assume that Alpha will pay for shipping to and from the repair facility, and absorb the cost of all parts and repairs.   Then there's the bridge in New York.  Sounds a lot like the old street vendor cartoon, with a sign that read, Double your IQ, or no money back.   ;)
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VE3WGO

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Re: ALPHA RF SYSTEMS
« Reply #24 on: March 22, 2023, 06:46:32 AM »

It sounds like owners of old (and new) Alpha amps are expecting lifetime warranties.

Is it true?

73, Ed
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KA4DPO

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Re: ALPHA RF SYSTEMS
« Reply #25 on: March 22, 2023, 09:58:33 AM »

It sounds like owners of old (and new) Alpha amps are expecting lifetime warranties.

Is it true?

73, Ed

That was not what I came away with Ed, I don't think anyone is dumb enough to expect a lifetime warranty on electronic equipment.  I don't know of any amateur radio manufacturer that offers a lifetime warranty.

Actually, 4 years is a lot longer than most amateur radio companies offer, it's normally one year from date of purchase.  however, in order to execute such a warranty, they would have to sell some amplifiers first and no one knows if that has happened.
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K7JQ

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Re: ALPHA RF SYSTEMS
« Reply #26 on: March 22, 2023, 02:08:22 PM »


I don't think anyone is dumb enough to expect a lifetime warranty on electronic equipment.  I don't know of any amateur radio manufacturer that offers a lifetime warranty.


Here's something novel. The KM3KM Mercury amplifiers have a one year warranty, parts, labor *and* shipping. After one year, they charge for parts and shipping, but labor is free. No time frame on labor noted, so I assume it's lifetime.
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