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Re: Simple spur fix

 

Further experimentation with Farhan's method,

Instead of removing R27 47Ohms and putting the filter there. I removed C22
and soldered the filter there.

The spurs on 20 dropped even lower @5W the spurs were -55 to -60dbm!
With proper termination the results may be better!

Raj

At 05-09-18, you wrote:

This fix reduced the spurs by up to 10 db? and requires ONLY ONE part to be added.
There is big change above 10MHz in the board. There is some improvement below also.

Farhan method of the same..much simpler and CW will work.

1. Remove R27
2. Solder the 45Mhz filter two extreme ends to the pads of the resistor.
3. Solder the center lead of the filter to the nearest ground. R13 is very near with a ground via.
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