No big science here, the venerable NE602 working as a mixer....again...
This was part of a NAVTEX receiver experiment. NAVTEX signals are around 490 and 518 Khz so I first built an PLL oscilator for those frequencies (for a DC receiver) but the PLL never worked like I wished so the idea was first to make the conversion to 4Mhz and then built a direct receiver around that frequency. Never did built the receiver but tested the converter against my TS-50 and it did received great.
The PCB schematic is not exactly the same in the paper (different input filter) but any design with the NE602 will work.
4 comments:
Schematic is close to unreadable.
Hello Tom,
Thank you for the comment.
For similar schematic with better re-ability see also here:
https://vk3ye.com/projects/projlfco.htm
https://circuit-diagramz.com/sw-converter-for-am-radio-schematic-circuit-diagram/
73!
Hi,
They say the NE602 performs better at a supply voltage around 8V.
73,
HA5OZ
Hello Zoltán,
Thank you for the input.
You are correct, with 8.5V conversion gain is a bit higher and noise figure lower but only noticeable above 30C.
73 de Ricardo/CT2GQV
Post a Comment