The Crystal Filter

The BSS, in it’s present incarnation, will have an IF at 9 Mhz and individual input RF bandpass filters for each ham band. The filters will be switched with FST3257 CMOS switches. A 6-pole, 9 Mhz QER crystal filter has been prototyped with low-cost ECS crystals from Digikey and looks very good. Here is the LTSpice design analysis:


9mhz_6P_QER

 

9M_6P_QER

 

Actual measured results are quite close. I’ll post them when I get a chance.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: