Re: SMD inductors for L5 and L7 replacement


I did notice from the v5 schematic that it still uses toroids, not shielded inductors. I am debating with myself a bit how necessary they are. In my own unit, the toroids seem to he okay, only displaying sensitivity on 40 meters, maybe mostly on CW. This has me thinking that my v4 experiences RF coupling into L5 on 7 MHz, where it then gets amplified by the BiDi amp and cancels with the excitation piped into the biased mixer (that then isn't a mixer but a resistive coupler). But why only on 7 MHz? I would guess it may be coupled from PA output. I should try same measurement of power into a dummy load for ssb, evaluating touch sensitivity of L5. My cw output dips a couple watts on 40m only, so its mostly a curiosity.  A visit to spectrum analyzer has been delayed, so no data yet to see if only adding input relays on a daughter board plus a 45 MHz LC filter is enough to cure spurious.

73 Curt

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