Monday, December 14, 2009

HF radio (4)

...The first sound.... not quiet what I was expecting but already some reception. The radio is a little deaf (no rf preamp and no rf input filter at this moment).
Made some more tests after this video, changed the first if preamp schematic a little bit but not much improvement, still have to check levels on sbl-1 mixers and verify all the if gain part of the cristal filter and mc1350. Basically at this point is copying equivalent to S2/3 on a commercial normal transceiver... I want a little more, also I already verified that the lower the noise the better to distribute the gain so will separate all the oscillators and different modules with some pieces od PCB.

Here's is another video at 20m band. Note that I changed the cristal filter relay in the middle of the board for a smaller one.

No comments: