Good stuff! ?You are in for a treat!
Start with the 455kHz stage, injecting a signal at the centre frequency just strong enough to detect. ?Align the detector first for best non-distorted signal. Then start aligning the IF filters, decreasing the IF input signal as you get more gain. Once everything is peaked to the Max you may want to de tune ever so slightly to widen the bandwidth. Which coil goes high and which goes low depends upon the arrangement. ?But don¡¯t overdo it.
Then check the 10.245 MHz oscillator and get it right on frequency.
Then proceed to align the 10.7. And the same goes for the first IF too.
I did a receiver with 82MHz first IF, using filters from a cellphone base receiver. Took a while, but it has great performance.
Dave
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On Feb 15, 2021, at 09:41, qwert0173@... wrote:
?Hello Dave.
Thank you for the answer.
I am radio engineer who most of the working carrier ( 30+ years ) was close but not quite with the radio related staff. My current project is a way to get back to basics. I am building a lab which will let me measure and tune IF filters.? QRP-Labs is a good resource, I will check.
Thanks again, qwert.
