Two assumed matching optocouplers do not provide the same linearity as a servo optocoupler with a single diode and two phototransistors. That is because the current to light and reverse linearity of the phototransistor is higher than that of the diode. Btw thermal droop is also a significant effect in the diodes and vary strong with the mounting thermals.
I noticed that some of your silk screen reference designators (ie R2, C5, etc...) were placed under the component. This means once the parts are installed you won't be able to see those designators. I always try to place them outside the part so after the board is assembled you can still see the R number or C number or whatever.
@@IMSAIGuy That microcap software looks interesting. But I use Linux and as far as I know, there's only kicad that will simulate on it. BTW I'm completely new to electronics, so I'm learning a lot. Thanks.😁
@@bigbazer I recommend TINA (Texas Instruments) as it is also free. Kicad will simulate but its very young and tricky to use if your not an advanced user, it is work in progress.
regarding that cut out if i dont have enough space should i do it under the tht parts or the smd parts ( i have a few isolators and a SIP7 smps that is isolated, what do you think?
The cutouts on these types of circuits is good standard practice mainly for visual indication of where an isolation is occurring, so technically not critically necessary. The dielectric of the fr4 is, in most cases, sufficient enough by itself. Just leave enough space on the traces to galvanically separate both sides of your circuit without capacitive coupling and you'll be fine
I found if the boards are very small you may get 15 for the magic $5. I sometime use tiny boards for the WH148 potentiometers. Solder the board to the pins and then the wires to holes in the board. About 15-20mm square.
Strong feeling it wouldn’t work without the dog on the PCB.
IMSAI Dog is always in control 👍
Good to see you selected a green board - as they say: Green is good for the environment :)
Geting output to optical fiber might be interesting. For high noise imunity preamps.
Two assumed matching optocouplers do not provide the same linearity as a servo optocoupler with a single diode and two phototransistors. That is because the current to light and reverse linearity of the phototransistor is higher than that of the diode. Btw thermal droop is also a significant effect in the diodes and vary strong with the mounting thermals.
In KiCad you can use num-slash to change where to place the bend at 4:00 before clicking to place the track.
You can reduce the grid size for routing so that the router has more flexibility.
I noticed that some of your silk screen reference designators (ie R2, C5, etc...) were placed under the component. This means once the parts are installed you won't be able to see those designators. I always try to place them outside the part so after the board is assembled you can still see the R number or C number or whatever.
Should have used U1B as the virtual ground.
You are right. Forgot I had a free one
Thanks 👍
9:01 the +12V LV side from the header to the decoupling cap is taking quite a detour through a via. Are you building an LC filter? 😉
Good ref for unused op amps:
You Tube: “Engineer It: How to terminate an unused op amp.”
Thank you for the kicad demo, it's definitely a great bit of free software.
Is it possible to simulate your circuit in kicad?
I recommend microcap (free) ua-cam.com/video/MsFkJTpsgdI/v-deo.htmlsi=wj63F77rc86FjejH
@@IMSAIGuy That microcap software looks interesting.
But I use Linux and as far as I know, there's only kicad that will simulate on it.
BTW I'm completely new to electronics, so I'm learning a lot.
Thanks.😁
@@bigbazer I recommend TINA (Texas Instruments) as it is also free. Kicad will simulate but its very young and tricky to use if your not an advanced user, it is work in progress.
@@andymouseHi, unfortunately it looks like Tina is a windows base software 🫤
@@bigbazer Oh sorry ! good luck with your search :)
regarding that cut out if i dont have enough space should i do it under the tht parts or the smd parts ( i have a few isolators and a SIP7 smps that is isolated, what do you think?
The cutouts on these types of circuits is good standard practice mainly for visual indication of where an isolation is occurring, so technically not critically necessary. The dielectric of the fr4 is, in most cases, sufficient enough by itself. Just leave enough space on the traces to galvanically separate both sides of your circuit without capacitive coupling and you'll be fine
@@sgctactics thx, i left 5mm solder mask/fr4 empty space i think this is enough then
What name of the CAD software you are using?
KiCad
I found if the boards are very small you may get 15 for the magic $5. I sometime use tiny boards for the WH148 potentiometers. Solder the board to the pins and then the wires to holes in the board. About 15-20mm square.