Power Modification Photos Uploaded
- I have just added two photos showing how to modify the power input of
the SoftRock. This is one way to provide power if you do not want to
run it from the USB port. Some have reported a lower noise-floor when
isolating the radio's power from the PC. Q1 is replaced by 78L05 5
volt regulator. R1 is not installed. In it's place, a higher voltage
version of C2 is used. I recommend something with a rating higher than
the 16volt cap supplied for C2 in the kit. I used a 35volt tantalum
cap. The original position for C2 is filled by a jumper wire. This
makes a convenient ground poit for testing.
In the close-up photo, you can also see C8, the coupling cap from the
local oscillator, has been mounted in a 2 pin header. This makes it
easy to disconnect the onboard oscillator. This way, you can use an
external clock source, like a DDS, in place of the crystal oscillator.
73, Bruce N1RX