EURO x0x-heart - Complete "Kit"

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Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sun Jan 24, 2021 7:59 pm

drop that to a 24k.
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constantG
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Re: EURO x0x-heart - Complete "Kit"

Post by constantG » Sun Jan 24, 2021 8:05 pm

Brilliant, it won't look good tho ;) Cheers for the help

Remann
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Re: EURO x0x-heart - Complete "Kit"

Post by Remann » Tue Jan 26, 2021 5:23 am

Hey guys,
I have a problem and don't know where to go from here.

I've built x0x-heart and peacemaker but I was so eager to finish so I soldered LM78L05 instead of bigger 7805 regulator as I thought that it should handle the max current that was reported 80-90mA, regulator rated at 100mA. What I didn't realize that it will not handle power dissipation and will not regulate properly. So after plugging in I've got 10.1V on the output instead of 5V. It took probably several seconds from powering up to the measurement but I switched off once I realized it's so off. Nothing blew up, no smoke, no visible damage on any of the boards.
Then I've got proper 7805 regulator, exchanged and powered up. Now all voltages are good but no sound at all.
I have 5.336V on J4-pin1 and 11.92V on pin3.
I measured voltages on power pins of all ICs and it looks good.
I tried different gate and CV sources in different combinations but no luck.
So questions are
How can I check if any of the ICs are burned?
What other voltages can I check to narrow down the problem?
Just to clarify, I checked all the small transistors that where pain to solder and there are no solder bridges. I re-flown them about 3x, taking care to not overheat but maybe they are more heat sensitive than regular SMD elements?

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Re: EURO x0x-heart - Complete "Kit"

Post by guest » Tue Jan 26, 2021 9:32 am

if nothing is getting hot, and your powersupply rails are good, then its probably safe to plug it in and test the signal path. you need to apply a CV over 1.5V to get sounds out, so make sure a CV is there. then check for CV out on J5. if that is good, then check for audio signals on J6. if thats good, then check for audio signal on J8. if thats good, check for audio signal on the volume knob. if thats good, check for audio on J7.
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constantG
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Re: EURO x0x-heart - Complete "Kit"

Post by constantG » Wed Jan 27, 2021 5:30 pm

I started building this and now realise that unlike every other build you don't just go ahead and throw everything on and hope for the best. So I soldered all the resistors on the pacemaker board. Can I still follow the guide from here or should I cut my losses and desolder and start again. i.e. can I still carry out the step by step testing with the resistors fully populated?

Cheers ;)

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Re: EURO x0x-heart - Complete "Kit"

Post by guest » Wed Jan 27, 2021 5:44 pm

yes, it should be fine. if numbers come up funny, post back and we can see if thats due to parts already being on the board.
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Re: EURO x0x-heart - Complete "Kit"

Post by Remann » Wed Jan 27, 2021 5:55 pm

Ok,
So I applied 5V square wave to V/oct and get:
J5 pin2 - 4.9V
J6 pin1 - up to 10V pin3 - up to 7.155V
J8 pin1 - 5V and slowly going down pin3 - 5.337V
But nothing on the volume connector nor J7. I tested max CW and CCW in case something might be inverted. Rest of the knobs in about the middle position. So does the heart values look ok?
I re-soldered all peacemaker pcb and found out that I have a spare LM555 so I switched to a new one but no luck and also changed TL072 - also no change.
Should I change the rest of the ICs or is there a way to test which one it would be? Unless it's one of the caps?

I'm also thinking - shouldn't I get some signal out if I plug in CV to cutoff or to VCF-IN? I tried all the switch positions i.e. square/triangle, internal/external with looking at signal on VCF-OUT or VCA-OUT but it's completely flat. No signal at all.

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Re: EURO x0x-heart - Complete "Kit"

Post by guest » Wed Jan 27, 2021 7:22 pm

do you have an oscilloscope? when you measured the voltages on J6, was that AC or DC?
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Remann
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Re: EURO x0x-heart - Complete "Kit"

Post by Remann » Fri Jan 29, 2021 3:57 pm

No, unfortunately no oscilloscope just multimeter. I have module with oscilloscope but I doubt has a proper resolution for it.
For J6 I measured DC. Should it be AC?

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Re: EURO x0x-heart - Complete "Kit"

Post by guest » Fri Jan 29, 2021 5:14 pm

yes, measure AC for J6. and you can try your scope module.
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Re: EURO x0x-heart - Complete "Kit"

Post by constantG » Sat Feb 13, 2021 9:34 am

I only have the Thonkiconn type jacks, can I use these but extend the ground pin with a resistor leg and if so, what would be the orientation? I'm guessing that P1 is the tip and P2 is the ring. Also, the pots I have are again from Thonk and have a larger foot on the side than the sweetwater ones in the BOM, are these purely used for stability?

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Re: EURO x0x-heart - Complete "Kit"

Post by guest » Sat Feb 13, 2021 4:21 pm

the thonk pots look the same as the smallbear ones in the BOM - alpha 9mm, so i suspect they will work. which part of the pot seems bigger? as long as its not the part that goes through the hole, its probably fine. as for the jacks, its hard to say without trying. im guessing there would be a way to make it work, though. on the pcb, the tiny hole and the one opposite that are both sleeve, the pad closest to the center is the normal switch, and the one further from the center is the tip.
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constantG
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Re: EURO x0x-heart - Complete "Kit"

Post by constantG » Thu Feb 18, 2021 11:57 am

I'm troubleshooting my build and have the following:

12V, 0V and 5V on U6
5.61V and 12.46 on pins 1 and 3 of J4
CV at J6

I have sound from the VCA but it is very filtered and extremely quiet. I can tell that the gate works but v/oct does not seem to track.

what else could I check and specifically what needs to be connected (ie. jumper wires etc) to test further

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Re: EURO x0x-heart - Complete "Kit"

Post by guest » Thu Feb 18, 2021 5:16 pm

connect everything up for testing and apply 2V or more of CV. if you dont get something out of the VCA, check the VCF out. if still nothing, apply an external signal to the VCF in and listen at VCF out and VCA out. if those work then its an issuse with the VCO.
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constantG
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Re: EURO x0x-heart - Complete "Kit"

Post by constantG » Thu Feb 18, 2021 9:12 pm

Thanks pal, I will check tomorrow (today)

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