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Good evening,

I'm looking for ideas as to some sort of integrated RF amplifier for this, preferably one that has additional filtering to make sure the spurs are fully dealt with.

Matthew Pitts N8OHU
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Sent from my Android device with K-9 Mail. Please excuse my brevity.

First off, do the daughterboard relay trick to help with the existing low pass filters.

Then consider adding individual bandpass filters (they make them for contesters and there are design papers on the ARRL site i believe) to help with other issues.

Fix the close-in spurs by dealing with the 45 MHz IF (the version 5 board may be a better choice)

Then take some well-behaved amp board and pair it with some heavyduty output filters built for it as well. -- or just buy something already out there on the market (but then it will be in a separate box)

I've finally gotten my Siglent Spectrum Analyzer but I haven't yet put it on my prototype V3 duaghter-board-modified rig -- too busy working to solve a noise problem at the local EOC where the spectrum analyzer has been HUGE in documenting the problem.

However, one think I *did* find was that my Heathkit cantenna attenuator tap was NOT comletely "level" -- it attenuated higher frequencies LESS -- so it made the receiver S-meter tests that I did, appear worse at higher harmonics than reality.

I'll get the spectrum analyzer on the board sometime...and find out if I should have used tiny coax for the input/output instead of plain wire like I did. I still need to replace the toroid that I destroyed with clumsiness in my first efforts to hack the traces.

Gordon


________________________________________
From: [email protected] <[email protected]> on behalf of Matthew Pitts via Groups.Io <daywalker_blade_2004@...>
Sent: Thursday, May 2, 2019 9:34 PM
To: [email protected]
Subject: [BITX20] RF Amplifier suggestions

Good evening,

I'm looking for ideas as to some sort of integrated RF amplifier for this, preferably one that has additional filtering to make sure the spurs are fully dealt with.

Matthew Pitts N8OHU
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.