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Re: ubitx spurs? Added LPF

 

John,

Very neat job on L5 and L7.

Make the 45MHz IF new filter with SMD parts. What seems to be the culprit is any vertical wire leads in that area
causes trouble. Solder the SMDs directly on the board.

When I get back to town tomorrow I will try it.

Raj

At 13/04/2019, you wrote:

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Well, that didn't go well.

Looking at it, the two toroids on the left are a little close.
I have a layer of grounded copper foil between
the PCB and the filter (insulated of course).

I might rebuild the filter lying flat.
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It looks like I only have 40m and 30m for SSB now.
Input is 1KHz 50mv p-p.

Harmonics on CW follow the spur tables.?? Only 80m is not usable there.

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