Re: a simple spur fix
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So no second 45mhz filter, no surface mount inductors at L5,L7, L1,L2,L3,L4 ?
TP13 is not shown in the v3 schematics, only in the v4 schematics.
I assume these mods work will work on the v3 boards too.
TP13 is the node at T2-pin3 in the first mixer.
I assume "across TP13" means that we add the cap and inductor in series from that node to ground.
Will be interesting to see if it matters where we physically place it, at T2-pin3 would be nice
because it could be added to the bottom of the board directly to the ground plane.
The second series cap and inductor get placed across C202, in the middle of the 30mhz low pass filter
on the far left side of the schematic.
So just leave C202 as it was, but add the cap and inductor from
the through hole pin for L2 (or L3) to the ground plane.
Will be interesting to see how picky we have to be about those inductors.
If we're lucky, they can be most any small surface mount inductor.
On Fri, Nov 9, 2018 at 07:35 AM, Ashhar Farhan wrote: