At 09:43 AM 2/24/97 -0800, Charlie Lofgren, W6JJZ wrote:
>Jim,
>
>One question--
>
>For the transmit preamp, you wrote: "A 270 pF capacitor should be added
>to the output of the U4B stage."
>
>Is that from the output to ground? (That is, in parallel with the 220
>ohm resistor, as you've redone the circuit?)
>
>Thanks,
>
>Charlie, W6JJZ
>
>
Indeed Charlie, in parallel with the 220 ohm resistor. I know it
in some ways doesn't make a whole lot of sense, but the results
on the scope are rather astounding. It also reduces the harmonics
the poor old IRF510 is amplifying by several dB. Good stuff for
such a simple change.
72....Jim
Jim Kortge, K8IQY (ex NU8N) | BMHA, NorCal, QRP-L
jokortge@tir.com | __o Cascade 17/40 SSB
Fenton, MI |_`\<, Mizuho 17/40 SSB
.... .. .. . . .. . (*)/(*) . . . . . ..
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