Yep I was thinking about hacking that trace up. have to search around to see if there is a ground but I couldn't find anything that looked near by on the schematic.? But maybe probing around might find something.? ? I'm hoping it wouldn't impact anything else except the spur.? What did you use to measure spurs on your board?
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On Wed, Jan 23, 2019 at 04:43 PM, Curt wrote:
Dave
I am thinking avoid drilling hole.? one must disconnect at R27 somehow to insert this new filter.? I think grounding C205 to some location near where you new filter will sit is most important - find a part connected to ground (use your DVM as continuity checker) and solder one end of a leaded cap there.? now find some way to place your 2 inductors together - could even be on a tiny piece of circuit board hacked into 3 islands, or a trace attached to TP13.? I am looking to try this mod myself but still thinking how I may do it.? After installing I need to verify it does not affect CW (like the xtal filter I tried) and then see if the mixer spurs are sufficiently reduced - I need about 10 dB per measurements we made at club building session.?
Curt
