Pavel, US4ICI and his team from vhfdesign.com are building a nice preamp for 23cm. Details can be found here:
http://en.vhfdesign.com/lna/lna-for-23cm-mmic-sky67151.html
It is doing a nice job:
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| 23cm LNA |
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| Passband with filtercurve from the ceramic filter, quite good input return loss |
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good suppression on 70cm
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| Noise figure measurement with HP 346B and Eaton 2075, with 10dB attenuator in front of the LNA its a bit worse abt. 0.5-0.6dB (for unknown reason) |
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| because the preamp is going to be used for tropo the second stage was removed, the gain is now lower |
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| its now 22dB @ 80mA |
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