220 or 1K resistors 4-pole mission

I swear I saw 1k marked on the control board of the 4-pole so thats what I used, anyway, I am getting all LED’s on and am thinking I should have stuck with the 220’s instead?

I am using standard green and red LED’s

I did see 1k on the control board!

Should I stick with the 1k resistors or go with the 220 like on all the other Shruthi control boards?

“The 220R resistors soldered at this step are current-limiting resistors for the LEDs - they set the brightness of the LEDs. The 220R value printed on the circuit board is suitable for standard low-intensity green, yellow or red LEDs - and a lower value could indeed damage the LEDs. For blue or white LEDs, a higher value, such as 1k, must be used.”

It’s all here: http://mutable-instruments.net/shruthi1/build/digital

Thank you elthorno, so I should desolder these 1k’s and put in 220’s instead? Would using the 1k resistors be a reason why my Shruthi is not booting?

If the LEDs don’t look too dim to you, the 1k resistors are fine.

These resistors just control LED brightness, and are not related to the boot problem you’re experiencing.

EDIT - see above.

Its working yeeeeeeeeeeeeeeeeeeehaaaaaaaaaaaaaaaaaaaaa

The CPU wasnt pushed in properly Everything works, everything,

I cannot believe I got this working first time, wow This Shruthi sounds so good!

Video of it working here

Olivier, I think I might love you a little bit, you are so talented and creative it just blows my mind how great these Shruthi synths are, the 4-pole is just incredible

Well that didnt last long…made sure all was working, put it in the case and now its not working lol

weak connection between the two boards?

or maybe a short caused by the metal tab of one of the regulators touching the control board?

I don’t know, It turns on now but the filter sounds odd, like the resonance is screaming…

I am not going to trouble you, or anyone else on here re my Shruthi builds…I’m sending it off to get repaired before I start messing about with it and ruin it

I suspect you have forgotten to save the “4PM” filter setting.

Take it out of the case and try it again. Check the 4PM filter setting as Olivier recommended, and make sure nothing is shorting or getting disconnected when you put it into the case. But, first of all, if you’re frustrated enough to send it for repair, walk away for a couple of days and then come back to it.

I sent an Anushri away for repair, paid for shipping both ways and the only problem was a disconnect in one of the IC sockets caused by using cheap sockets. I also ended up sending a complex Eurorack VCO (Dual Ultrafade from J3RK) to England for repair and the only problem was a bad batch of TL072 ICs. Expensive shipping from Canada to find a defective five cent part.

I also had a Dual 258J VCO that I could not figure out. Ended up leaving that on the shelf for a few months before getting back to it and getting it working. I may be stupid but at least I’m tenacious.

I did forget to save it first time around :slight_smile: but have since saved it and it still does odd things.

Thanks piscione, sound advice! I might try a couple of things and check for shorts as Olivier says, but if this not working like it was 1 hour ago, its going to a professional…

I have a spare TL072, I might try replacing it to see what happens :smiley:

Try touching the board, pressing ICs, pushing parts… while it is powered, it’s a good way of finding loose connections and solder joints.

Okay will do, thank you :slight_smile:

Now my unit is fffffffffffffff ed

Its just flashing on and off, the screen and the LED’s

I am sending it off to be repaired

The 2164 is fried, I took it out and the unit booted, but the powerside of the board got hot quickly so I tuned it off…

Took me two weeks to get that freaking IC grrrrrrrrrr

With the board upside down, I am checking voltages on the main power input, the pins on the jack socket are only giving me 3v, tried a different psu, same problem…

What could cause that? the LT1054? A capacitor?

Probably because there’s a short somewhere draining all the power your poor PSU can deliver.

First of all, remove all ICs, and check that you get a good +5V. If your V2164 is fried, it’ll short the power rails. And the V2164 can fail because of a missing negative rail. And the negative rail might be missing because of a short somewhere else or a problem with the LT1054.