Carl wrote:
> To the obsessive I agree and I fit that description on 160M and VHF
> and up.
> However many dont get that involved and run 1" hardline, buy a
> hilltop, erect big towers and antennas, etc, etc (-;
>
> The 3-500 is rated to 110 mHz at full power and is a fine, efficient,
> 6M tube. The 572B is actually rated to 54 or 60 "mc" in some old
> descriptions. Ive yet to have a problem getting 40M performance on 6
> with them.
>
> Ive converted several 2 and 3 hole Alphas, its the tube cost that
> scares off many, a 2 holer isnt any more output than a SB-220 if you
> want long life.
>
> Id rather use a 2 3CX800 or a single 8877 and dont push it to 2500W
> unless you are a nitwit with lots of money.
Agreed, but what's wrong with 2 8877's? They should last forever at
1500 out in that 6 n' 2 amp in the handbook. <:-)) True, they're not
cheap, but if you want the best...Tubes should always be used as a pair,
except for 813's and 572's and then you use 4 of them.
I kinda like the looks of a pair of 833's for HF with a window that lets
you watch and partake of the "warmth" of those big bottles without
having to deafen yourself with fan noise. Put a pair of those in a glass
cabinet with the exception of the front panel (where you could still put
in a window). Admittedly the two pins on top with one being the grid and
one the plate can be a bit confusing and does look a little odd.
OTOH I used to get a "lot" of glow out of 4 813's on HF (80-10) with the
B&W tank coil. Even a pair of 813's seems to have surplus emission, but
I don't know how long they'd last.
Then again a pair of 6C21s/750THs in PP on 6, using a pair of vertical
pipes about 3' long for the tank circuit is impressive.
I have to admit there is a certain psychological rush to seeing those
big bottles light up. <LOL>
73
Roger (K8RI)
>
> Carl
> KM1H
>
>
>
>
> ----- Original Message ----- From: "Roger" <sub1@rogerhalstead.com>
> Cc: <amps@contesting.com>
> Sent: Wednesday, December 02, 2009 8:52 PM
> Subject: Re: [Amps] Advice
>
>
>>
>>
>> Carl wrote:
>>> Is a 1-2dB increase worth it?
>> "To me" chasing DX, working Aurora, or contests, every db counts.<:-))
>> Although the 3-500's and 572Bs are considered poor tubes for VHF due to
>> the long internal leads, they work quite well in a properly designed and
>> constructed circuit.
>>
>> I'd think the old Alpha 76 series would make really good subjects for
>> mods, but there many amps out there for less money that will suffice and
>> "in general" it is far easier to modify an existing amp than build from
>> scratch.
>>
>> 73
>>
>> Roger (K8RI)
>>> The LK-450 is built rugged and is a good
>>> platform. Since Ive converted over 200 SB-220's to 6M Ive got no
>>> complaints
>>> there but its easy availability is why it is so popular.
>>>
>>> Carl
>>> KM1H
>>>
>>>
>>>
>>>
>>> ----- Original Message ----- From: <Gudguyham@aol.com>
>>> To: <n8de@thepoint.net>; <amps@contesting.com>
>>> Sent: Wednesday, December 02, 2009 6:24 PM
>>> Subject: Re: [Amps] Advice
>>>
>>>
>>>
>>>> Excellent advice Don, But an Sb-220 is superior!! Lou
>>>>
>>>>
>>>> In a message dated 12/2/2009 10:48:06 A.M. Eastern Standard Time,
>>>> n8de@thepoint.net writes:
>>>>
>>>> Save money and time.
>>>> Sell the LK and buy a ready-made SB200 conversion from one of the
>>>> experts who do that. W1QJ is one of those guys.
>>>>
>>>> Standard disclaimer .. good guy to do business with from a satisfied
>>>> customer.
>>>>
>>>> Don
>>>> N8DE
>>>>
>>>> p.s. I might buy the LK if you want to sell it.
>>>>
>>>>
>>>> Quoting Phil LaMarche <plamarc1@verizon.net>:
>>>>
>>>>
>>>>> I have an LK 450 Amp Supply amplifier with vacuum relays etc that
>>>>> I'm
>>>>> considering the conversion to 6 meters. Want to hear from you if
>>>>> this
>>>>> is
>>>>> the way to go or should it be another model for conversion?
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Phil
>>>>>
>>>>>
>>>>> Philip LaMarche
>>>>> LaMarche Enterprises, Inc.
>>>>> <http://www.instantgourmetspices.com/>
>>>>> www.instantgourmetspices.com
>>>>>
>>>>> www.w9dvm.com <http://www.w9dvm.com/>
>>>>> 800-395-7795 pin 02
>>>>> 727-944-3226
>>>>> FAX 727-937-8834
>>>>> NASFT 30210
>>>>>
>>>>> K3 #1605
>>>>>
>>>>> CCA 98 00827
>>>>> CRA 1701
>>>>>
>>>>> W9DVM
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
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>>>>>
>>>>>
>>>>
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