[HomeBrew] Direct conversion receiver

[James Kearman]

R. Blackman wrote:
> I have replaced the  MRX-40 oscillator with the DDS input, and the input filter / gain pot with the bandpass filters.
>   

What is the insertion loss of the filters?

> although selectivity is very good, the sensitivity is weak. If I inject a signal generator in place of the antenna, wow, nice and loud!

Does your signal generator have a true 50-ohm output impedance? Your
results imply your receiver matches to the sig-gen impedance better than
to your antenna.

73,

Jim, KR1S
http://qrp.kearman.com/