7 Jul 2012

Ceramic filters on 472-479kHz?

An eBay seller from Hong Kong has 100 off 472kHz DIP ceramic filters on sale for £5.31 delivered to the UK. See item number 400305093888.

Some filters similar to this have useful bandpass characteristics and acceptably low insertion loss (around 3dB), so may be seriously useful for 472-479kHz rigs and transverters. For example, as a roofing filter to protect a RX after a small gain stage, or as a filter to clean up the output of a transverter at low level before applying a signal to a driver and PA. I guess they must also be useful in a ceramic stabilised oscillator.  Anyone used these in similar applications?

1 comment:

Erwin said...

They claim that it is a SFU465B filter. However, as far as I know Murata uses the next type number convention :


where LLL is the the series name, NNN is the center freq. in KHz, and T is the type.

So a SFU465B should have a centre freq of 465 KHz.