What kind of filter is this? FM?

tomhouston

Member
Joined
Aug 28, 2011
Messages
10
Location
Chantilly, VA
I found this device (I think it's some sort of FM filter?) while cleaning out my fathers basement but have no idea what it is. I'm 100% sure it's his design/build but would like to know what it's actually used for if anyone knows.

IMG_Filter.jpeg
 

merlin

Active Member
Joined
Jul 3, 2003
Messages
3,131
Location
DN32su
This is a converter, Has a filter centered at 21.4 MHz. the small can is a diode ring mixer.
Bottom BNC is likely filtered IF output. Top left, from the protection circuit likely RF input(ant ?)
Top right, oscilator input.
So, the heart of this is the MD-108 mixer. with datasheet, you canuse this as some up or down converter.
 

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