>At 10:22 AM 29/02/2004 -0500, Ed Briggs wrote:
>>Regarding glass windows, I've seen them in pictures, and always wanted an
>>amp with one, but was always concerned about RF leakage and the possibility
>>of long term exposure to VHF harmonics, particularly when I got up close to
>>the window to admire the tubes.
>>
>>Are there practical techniques to safeguard against these issues in HF amps?
>>I like the way a 4-1000a looks too..
>
>
>
>Surely, a front door glass and screen from a microwave oven would do the
>trick.
** No screen is needed since a 15cm by 10cm or so viewing window would
be a waveguide below cutoff for anything a 4-1000A could produce.
cheers, Alek
>
>Alek, VK6APK
>
>
>>(The emphasis here is on safe nostalgia, not contemporary design
>>techniques.)
>>
>>Regards to all
>>
>>Ed
>>----- Original Message -----
>>From: "Mike McCarthy, W1NR" <w1nr@eecorp.com>
>>To: "P. Coppin" <copa054@cira.it>; <Amps@contesting.com>
>>Sent: Saturday, February 28, 2004 9:26 AM
>>Subject: RE: [Amps] 2 x 8877
>>
>>
>> > The Alpha SX had issues on 10M because of the capacitance of the two
>> > tubes. Also, 2x8877 is more expensive than 3x3cx800. With the 3cx800,
>> > the plate voltage is lower, required capacitance is lower, voltage
>> > ratings of tank components is lower translating into a more cost
>> > effective design.
>> >
>> > Still, nothing impresses me more, at least visually, than a pair of
>> > 4-1000's built into a cabinet with windows...
>> >
>> > Mike, W1NR
>> >
>> >
>> > -----Original Message-----
>> > From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
>> > Behalf Of P. Coppin
>> > Sent: Friday, February 27, 2004 8:29 AM
>> > To: Amps@contesting.com
>> > Subject: [Amps] 2 x 8877
>> >
>> >
>> >
>> > First of all, sorry for my poor english.
>> >
>> > I would like to know the reason why the amps manifacturers build linear
>> > amps
>> > using three 3cx800a7, 2 3cx1200a7, one 3cx3000a7 and ruskies but no one
>> > build a linear amplifire with 2 3cx1500a7 (8877) such as the Alpha sx.
>> > What problems they could have ?
>> >
>> > 73
>> > Paul i8ixo
>> >
>> >
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>> >
>> >
>> >
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>
>http://www.qrz.com/vk6apk
>http://profiles.yahoo.com/vk6apk
>
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