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I'd like to make a preamp for 11m. Not sure where to start though. I think I would try using a geared variable capacitor in parallel with the best inductor I can build and have it resonate on 11m. The antenna jack would be tapped at a low impedance point on the coil and use ether one of these jfets or mosfets to sample off the top of the tank. Not sure how the antenna will load it down, but the fets shouldn't load it much. If I can keep the BW to a couple dozen kHz or so in that first amp and use one of those low noise parts there, I think i'd have it made. The noise figure on these low noise jfets and mosfets are both 1dB at 100MHz, so I'd think they would do better at 11m. I don't know...

[QUOTE="brandon7861, post: 812035, member: 53724"] I'd like to make a preamp for 11m. Not sure where to start though. I think I would try using a geared variable capacitor in parallel with the best inductor I can build and have it resonate on 11m. The antenna jack would be tapped at a low impedance point on the coil and use ether one of these jfets or mosfets to sample off the top of the tank. Not sure how the antenna will load it down, but the fets shouldn't load it much. If I can keep the BW to a couple dozen kHz or so in that first amp and use one of those low noise parts there, I think i'd have it made. The noise figure on these low noise jfets and mosfets are both 1dB at 100MHz, so I'd think they would do better at 11m. I don't know... [/QUOTE]

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