I know, just making a point that the tube will easily do more than 1500
watts, as the other guy stated. I am more than happy having that tube
running at 1200 watts and hopefully lasting for a few years that way.
I am sure the IMD plots would look wonderful at 2600 watts SSB:-) I would be
the only station on 17 meters.
By the way Karl, I was going to buy a spare tube and I see some for sale for
around 600 bucks, but they are imports, I guess Chinese, are they as good as
my Eimac 8877 original?
Mike
-----Original Message-----
From: Carl [mailto:km1h@jeremy.mv.com]
Not unusual since it is seriously overdriven. Id love to see the IMD plot on
SSB at the same power.
Carl
KM1H
----- Original Message -----
From: "Mike" <noddy1211@sbcglobal.net>
To: "'Amps Reflector'" <amps@contesting.com>
Sent: Thursday, July 24, 2008 9:16 PM
Subject: Re: [Amps] Fwd: Re: Bill Orr comment
> My Al-1500 (8877) will do 2,600 watts into a dummy load key down on 17
> meters with 100 watts of drive as measured on an LP-100.
>
> Mike
>
> -----Original Message-----
>
>
> Bill Orr was hardly a quack. Very knowledgeable and nice guy, met him
> several times over the years. An 8877 will get pretty darn close to 2 X.
> It
> was used in at least one 2.5 KW commercial FM transmitter that I know of
> and
>
> by FCC rule the transmitter had to be capable of 110% rated power (2750W).
> And that is CCS!
> 73's
> Chuck
> W6RD
> ----- Original Message -----
> From: <k9mk@flash.net>
> To: "Commander John" <crazytvjohn@yahoo.com>; <amps@contesting.com>
> Sent: Wednesday, July 23, 2008 11:01 AM
> Subject: Re: [Amps] Fwd: Re: Bill Orr comment
>
>
>>
>> I can't speak to todays class of ceramic tubes but in the 70's I
>> built
>
>> a number of 3-1000Z amps. The rule of thunb for a well designed AB amp
>> was 2:1, output power vs. dissipation. So, yes I agree with the Orr's
>> "rule of thumb" here. The 3-1000Z typically did 2:1 RF out 80m-15m but
>> it
>
>> did require a well thought out RF deck. I will not name names here but I
>> saw a dozens of what I call stressed 4-1000A amps that made it to the
>> 2.5:1 ouput ratio.
>>
>> It is probably related to the manufacturers design but I have never
>> seen 3KW from an 8877 or even 1600W from a 3CX800... Either something is
>> being lost in translation or it kinda makes you wonder about the claims
>> surrounding our modern ceramic tubes...
>>
>> 73's Mike K9MK/5
>>
>>
>>
>>
>> -------------- Original message from Commander John
>> <crazytvjohn@yahoo.com>: --------------
>>
>>
>>>
>>> Commander John wrote: Date: Wed, 23 Jul 2008 10:23:38
>>> -0700 (PDT)
>>> From: Commander John
>>> Subject: Re: [Amps] Bill Orr comment
>>> To: Peter Voelpel
>>>
>>> Who is this "quack" guru?
>>> john w9zy
>>>
>>>
>>> ~~~~~~~~~~~~~~~~~~~~w9zy
>>>
>>> Peter Voelpel wrote:
>>> 2-2.5 times the dissipation is normal.
>>> Assume 1500 out, at 70% efficiency that is 643W dissipation,
>>> 1500/643=2.33.
>>> Eimac claims 75% efficiency on their 3CX3000A7 datasheet in AB2.
>>>
>>> 73
>>> Peter
>>>
>>> -----Original Message-----
>>> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]
>>> On
>>> Behalf Of Gudguyham@aol.com
>>> Sent: Mittwoch, 23. Juli 2008 18:30
>>> To: amps@contesting.com
>>> Subject: [Amps] Bill Orr comment
>>>
>>> I was reading the Bill Orr handbook and on his section about amplifiers
>>> he
>>> says.....A properly designed grounded grid amplifier should produce 2 to
>>> 2.5
>>> times the plate dissapation of the tube in output. He did not put any
>>> limitations on the statement as to IMD or anything like that. He did not
>>> say if the tubes ratings would be surpassed (I am sure they would), but
>>> I
>>> think what he was saying is that the tube should continue to make power
>>> to 2
>>> to 2.5 times it's dissapation before it would not make any more power
>>> and
>>> flatten out.
>>>
>>> Upon speaking with an amp "Guru" about this subject, he procalimed that
>>> Bill Orr was a "QUACK". The basis of his claim was that he was never
>>> able
>>> to build an amplifier that obtained that kind of results.
>>> What say you? Lou W1QJ
>>>
>>>
>>>
>>> **************Get fantasy football with free live scoring. Sign up for
>>> FanHouse Fantasy Football today.
>>> (http://www.fanhouse.com/fantasyaffair?ncid=aolspr00050000000020)
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>> _______________________________________________
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>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>>
>>>
>>>
>>>
>>>
>>> W9ZY
>>> .... Commander John ....
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> W9ZY
>>> .... Commander John ....
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>> _______________________________________________
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