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Re: sBITX

 

Not the ceramic ones, you get xtal ones.. a little pricy but sharp stopbands.
Basic ones are 7.5 KHz, I am sure wider ones are there. Probably in 21.4MHz.

At 05/06/2021, you wrote:

Raj,?
I evaluated a few 10.7 mhz fm filters. Their stop-band rejection was hardly 50 dB, not enough for HF radio.
Btw, the sbitx scheme does not stop using a narrow cw crystal filter. The entire IF strip is broadband. So, you switch in the?? cw filter (lets say at 9 Mhz) and change the LO and BFO by reprogramming the Si5351.
- f

On Sat 5 Jun, 2021, 9:32 AM Raj vu2zap, < rajendrakumargg@...> wrote:
Farhan,

Use a 10.7 filter!

Raj

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