Thanks Gyula, HA3HZ, for your indications on how to lift the pins of the IC's U6 and U7. I have done so, but the Softrock remains the same, the 5V voltage keeps dropping and I can't find the cause. I have uploaded some pictures where you can see PIN 8 of ICs U5 and U6 separated from the board. I would like to recall that the replacement of the 78L05 was carried out because I thought that the voltage dropped because it had been damaged, but I was wrong, unfortunately I broke it and had to replace it with a 7805 instead.
Thank you Chuck Nolin, WA6LTV / 4, for your guidance. I also attach photos of the Si570. This afternoon I checked that the oscillator works perfectly, connecting the Softrock to the USB cable of the computer, starting the CFGSR software and tuning the output frequencies of the Si570 with an hf radio. The jumpers of J2 i'll correct at the future.
Thank you Ismo, OH2FTG, for your indication about the 7805. Before mounting the 7805, I read its technical data sheet and also checked -outside the Softrock- that its operation was correct.
I would like to recall that the receiver was working perfectly at the end of the RX OpAmps part, but it all broke the moment I completed the TX OpAmps part.
In the TX OpAmps stage, I have checked with a multimeter the value of the resistors, they are all correct, but the values measured in R21 and R22 is does not correspond to that of the real resistors. The resistor on the board R21 and R22 are 2.21K, but I measure 1.1K.
Also in the Dividers stage, the same thing happens, the resistors R13 and R14 do not correspond to that of the real resistors. The resistors on the board R13 and R14 are 10K, but I measure 5K.
The values of these resistors are divided by two in the circuit. Is this correct, or is it the consequence of a fault in another part of the circuit?
I have uploaded new images of all these comments. There are here:
/g/softrock40/album?id=269060Thank you very much for the help you are giving me.
73,
José María, EA4B
