i4jmy@iol.it wrote:
>Statistically, the overall reliability is also an inverse function of
>the number of components used.
>The point if adopting some newer and more complex circuit, other than
>for didactical purposes, should always be related to the evaluation of
>the real advantages gained.
The main advantage is in reducing the risk to an expensive tube.
That's why I haven't got around to building OE5JFL's circuit yet -
GS35Bs are cheap!
On the other hand, many UHF QRO operators use TV transmitter tubes which
are not available any more, but they are the only ones that will deliver
the power at those frequencies. If their last good tube fails, the whole
amplifier is scrap, so they build in much more protection.
>> ---------- Initial message -----------
>>
>> From : owner-amps@contesting.com
>> To : amps@contesting.com
>> Cc :
>> Date : Tue, 28 Nov 2000 10:39:18 +0000
>> Subject : Re: SV: [AMPS] SB-220 Glitch Resistor ???
>>
>>
>> sm5ki wrote:
>> >
>> >How about a thyristor in paralell with the hi voltage? You make a
>simple
>> >STEPUP ignition transformer by simply passing the B plus lead
>through a
>> >multiturn coil. An old idea from an old SHORT WAVE MAGAZINE article?
>The guy
>> >who wrote it has been on this reflector and the article was part of
>a series
>> >of articles on a K2RIW. Very complicated but very informative, I
>remember.
>>
>> This keeps on coming around. OE5JFL now has an English-language
>version
>> of his thyristor crowbar on his own site, with readable schematics:
>>
>> http://www.qsl.net/oe5jfl/flashover.htm
>>
>> That solution is better than a glitch resistor, but it also requires a
>> lot more effort.
>>
>> 73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
>> 'In Practice' columnist for RadCom (RSGB)
>> http://www.ifwtech.com/g3sek
>>
>> --
>> FAQ on WWW: http://www.contesting.com/FAQ/amps
>> Submissions: amps@contesting.com
>> Administrative requests: amps-REQUEST@contesting.com
>> Problems: owner-amps@contesting.com
>>
>>
>
>
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.com/g3sek
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
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