Polyvoks page : No power test?

Hello ! I’m back !

I’m building a polyvoks filter, but i didn’t find any power test to do (the schema with blue, green and red point.) There is something somewhere ? I can create it if you want. You just have to tell me where are the point to check.


Well, seeing that what your testing for is that you’ve set up the power supply properly and you aren’t going to fry your chips you should grab the schematics and make sure you complete all the parts in the power supply section. If you compare some of the other test point photos and check out out some of the data sheets for any of the chips you’ll notice that the test points are the /- voltages for the chips. So look at all of your chips and google for their data sheets. Look on data sheet for the/- pins, measure the corresponding voltages in the socket for those pins.

Ok, i checked the datasheets. Am i right ?

I think on the TL084 it should be pin 1, but I’m on the road and have no data sheet. The Decoupling 100N is on Pin i so i suspect this… BTW, you can’t damage anything by measuring remittances so my personal PowerCheckProcedure™ is just to poke around somewhere near i remember the power could be (next to the 100Ns) and see if i can get somewhere a nice ± 5V. I highly doubt that a PCB is faulty so i don’t check every chip…

I think on the TL084 it should be pin 1, but I’m on the road and have no data sheet
no, on quad opamp packages the power pins are the middle pins. It looks right to me. Don’t forget to check on the 4053 and the 595 chips - I think it’s 8 (negative supply) and 16 (positive) but I might be wrong.

MicMicMan is right - i just got a Datasheet thru T-Mobiles snails speed EDGE delivery… I’m a bit confused about the position of the decoupling Cap…

The 595 being a pure logic chip has only GND at Pin 8 and Vcc(+5V) at Pin 16, the 4053 being kind of hybrid digital/analog needs an additional negative Supply if you want to switch Audio on PIN 7(above the GND).

Should i be worried remembering all this by memory?

the decoupling cap is perfectly ok if you look at the traces.

Should i be worried remembering knowing all this by memory?
well… if you have enough v2164 on stock this should be alright…

yups, i was a bit confused by the 100N near pin 1. I shouldnt look at Polviks PCBs while traveling in a Car in the Rain. At least i remove away my Wifes Music from the USB Stick - i am so clever :wink:

I remember that VEE = 0V, and VCC = 5V

So it’s pin 7 or 8 for the 0V (Because it’s GND or VEE or Q7)

Also, I remember that yesterday I tried to mesure between GND and 5V on J6, but I just had 0. Is it normal ?

I will check that tonight, and give you my mesurements.

have a nice day ! Bye

it should be GND (blue dot) for both 4053 and 595 pin 8. If you look closely those are thermal pads, thus they are connected to ground :slight_smile:
Some pins of the opamps and the OTAs are connected to the GND as well, but I doubt that it’s very useful to check it with your multimeter - you could label them as an exercise though (look at the schematics for that)

Ok, filter board was perfect ! the other board now !