Matching SA602 mixer to SA605
I am looking for a reasonably efficient method of coupling a 602 mixer
output to a 605 input at 45MHz.
I have tried a tuned circuit with coupling caps and did not get good
results. Both the 602 and 605 are working fine independently. (I tested
the 605 with a match up from 50 Ohms to 1k5).
I am wanting a receiver with around 10dB signal to noise ratio at -115
to -118dBm.
Signal frequency is 151 MHz.
1st IF is 45MHz, 2nd IF is 455kHz(+/-15 kHz bandwidth).
The input filter has a bandwidth of 6MHz.
The image should not be an issue as it is way down at 60MHz.
I don't want to loose much gain between the 602 and 605 (about 3-5dB
would be acceptable).
Thanks in advance
Regards
David
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