There has been a complete 8877 design in QST years ago for 6 mtrs with a
stripline by a guy Meade (second name ). He also designed a 2 meter amp.
Have no time to find the article right now, It may also have been in one of
the ARRL handbooks.
Prosit de Hans SM5KI member of RSGB
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>Från: "Chris Tran GM3WOJ" <gm3woj@talk21.com>
>Till: <amps@contesting.com>
>Ämne: [AMPS] 50MHz 8877 amp. plate circuit - Summary
>Datum: tor 11 maj 2000 20.36
>
>
>Thursday 11th May
>
>Thanks to everyone who replied to my posting - lots
>of helpful information,ideas and different designs.
>
>I'll collate all the responses and post them on my
>web-pages www.qsl.net/gm3woj/
>as soon as things are back to normal at qsl.net.
>
>My thoughts after having studied the information are:-
>
>1. With 4CX1000A, 4CX1500B and 8877 amplifiers,
>50MHz is approaching the max. frequency for using a
>Pi or Pi-L circuit. (I have a 2 x 4CX250B amp. which
>uses a Pi tank on 70MHz - just!)
>
>2. 'Established' 50MHz designs are not so easy to
>repeat in practise - many are very component-specific,
>layout-specific and/or operating-conditions specific.
>Even using identical components, layout and operating
>conditions does not guarantee that the amp. will behave
>as expected. Some designs seem to work by good luck
>rather than good design.
>
>These are pretty obvious statements I guess ! I've now
>got the tank circuit to resonate, but efficiency is only 48%
>so I've quite a few improvements/changes to make.
>(There is no DX to work on 6m from here at the moment!)
>
>Look for some photos of this 6m amp. and other amps.
>on my web-pages soon, and also check www.gm7v.com
>
>73
>Chris GM3WOJ
>gm3woj@talk21.com
>
>
>
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>
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