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Re: Spurs/Harmonics fixes for v4 based on v5 board design?

 

What inductors did you use, please share a pic.

There is always a carrier leak at 12Mhz and 12-7 = ~5 Mhz could be what you see.

Most spurs are created by the harmonics of the carrier feeding back to the first BiDi amp. Changing to Axicom relays
eliminates a lot of these dancing dervishes.

Raj

At 02-02-19, you wrote:
Thanks I'll try the two tone test next. Tonight I replaced L5 and L7 Raj's fix to see if I noticed any differences. Using LSB on 7.15 into 40db attenuator get-55db main signal and I see some sort of spur at around 5MHZ that is about -85db, doesn't fluctate with voice it's constant when I key the transmitter. Wonder what could be producing around 5 MHZ.

I wonder if the v5 board redesign changes next might help. Might see if I can figure out where on the board that could be introduced.
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