Salas, sorry for the slight offtopic, but could you please post a link to the L-Adapter schematic?
I downloaded and burned on mini SD card this image from your list of players to test. I use Foobar on W10 mini PC myself. I don't know how to go about this cruel RPI decapitation stuff 😀
Attachments
Not proof finished yet. When it will work well on its own power source and PCB, it will also get its own thread with full info.
OK I also burned that one's image and run it. 522mA max (moments) and 212mA average during boot. Then it turns the HDMI off, the green lights don't blink anymore, and it pulls 217mA steadily.
Attachments
Hi,
I've built the +- ultraregs for 15V and they are running fine.
Built up a +V ultrareg for 5V.
These are tea-bags pcbs & kits. The +5V kit came with PF5102
jfets marked as 8.9 4.4 9.0 .
For the J3 position I used the 4.4 jfet.
Powered up the pcb with a 9volt xfmr and no load on the output
and the output voltage is 12+ volts and cannot be adjusted with
the pot.
Any suggestions as to what I can check for, all solder joints look
good and none bridged. I need to verify resistor positions and
values, all resistors were metered before installing.
Thanks Ichi-
I've built the +- ultraregs for 15V and they are running fine.
Built up a +V ultrareg for 5V.
These are tea-bags pcbs & kits. The +5V kit came with PF5102
jfets marked as 8.9 4.4 9.0 .
For the J3 position I used the 4.4 jfet.
Powered up the pcb with a 9volt xfmr and no load on the output
and the output voltage is 12+ volts and cannot be adjusted with
the pot.
Any suggestions as to what I can check for, all solder joints look
good and none bridged. I need to verify resistor positions and
values, all resistors were metered before installing.
Thanks Ichi-
Attachments
Then Q2 & Q3's Vbe. Circa 0.61V each would be healthy. By the way when having a 20k voltage trimmer (VR1) it may take quite many turns before it will respond for lowish settings. Since that value is to cover a large 5V-40V output range, and as it comes midway set from the factory, it should be trying for about 25V in this circuit.
No shorts of tabs to HS.
Will check Vbe s .
On the pot I ran it all the way up & back, with no voltage variation.
What the wha ?
I just checked the op voltage again and twiddled the pot and got it down to 5V steadt ??? 😱🙂 😕
I just checked the op voltage again and twiddled the pot and got it down to 5V steadt ??? 😱🙂 😕
I had to dig out my skinny meter probes to get down to r7 and it reads .54V
and now the Vbe of q2 & 3 is 0.6V ----
and now the Vbe of q2 & 3 is 0.6V ----
That's 2mA Iq. Both that and the Vbe spot on by the book. Run over the pot's joints with the iron and some extra solder. Just in case it was about a bad joint.
