FRUKU Oktra - DIY Build

As the fall season is upon us, we found ourselves going through our backlog of modules and came across the FRUKU Oktra. We have had this kit for some time, and now it was finally time to bring it to life. The Oktra has four independent outputs which can be controlled simultaneously with one knob (Macro Knob).

The four outputs all feature an attenuverter and two output sockets. If you also plug in an external signal, the macro knob is then bypassed and the module will function as a attenuverter/multiple. Sounds fancy eh? Let’s get on with the build shall we?

Links and more links…

Below are a series of links that have been provided by FRUKU to help assist with the use, building and buying of the Oktra.

Of course, we are here for you as well if you have any questions while building the module. Just hit us up on our Contact Page.

Resistors and Diodes

As with all DIY kits, start here first. The resistors do not have a specific orientation due to their lack of polarity so you can place these according to the BOM. Diodes on the other hand have polarity that matters. Make sure to match things up with the PCB silk screen and tack everything down. 

IC Socket and Power Header

Next up, we mounted the power header (on the back of the PCB) by placing the part and then adjusting with solder as we tacked it down. This helps keep things lined up as you place the part. When soldering the IC sockets, keep the ICs out for now. You will place these right before you complete the module. 

FRUKU Oktra - Time Lapse Build

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There are 2 different types of caps on the FRUKU Oktra. You have 2 electrolytic caps that will need to be placed on the backside of the PCB (next to the power header). Since polarity matters with these caps, make sure you have the long leg of the cap line up with the “ + “ sign on the PCB.

When this is complete, tack them into place and trim the leads. As for the rest of the caps, they are box/film caps that do not have a specific orientation. Pop these into their homes and flip the board over to solder them into place. 

Jacks and Pots

Before calling it complete, don’t forget about the 9 jacks and the 5 pots. The jacks can be placed in sections and it helps to tack down the ground leg as you move along. This way if you need to adjust anything, you can reheat the leg and move the part. After placing all of the jacks, start mounting the pots. There is one metal pot and 4 plastic pots that make up the Oktra. The metal pot is your macro knob and is mounted with a nut and washer.

FRUKU Oktra - Build Gallery

Wrapping Things Up...

When you have completed mounting the jacks and pots, place your ICs and set the front panel. 

We used our IC leg bending tool to ensure that the legs were a perfect 90 degree prior to mounting them. Lastly, place all of the nuts on the jacks and tighten everything down followed by mounting the clear knob on the metal pot. You have now completed the Oktra module by FRUKU!

Final Thoughts

Prior to patching, we tested our module in our test rack and it all worked flawlessly. In the end, the Oktra by FRUKU was a fun module to build. It was quick and easy and didn’t really require a lot of “brain” power to complete the build. Aesthetically speaking, the Oktra matches its brethren modules by FRUKU. There is a clear macro knob and its’ panel is black with white design elements. It looks great! 

Since it is a utility module, we will be tinkering around with it throughout our studio/synth time. As of the time of this review, we have patched the module multiple times and we have to say its pretty fun to tinker around with. Although this module is not a “must have”, it is definitely a “really nice to have” module. Head on over to FRUKU’s page and pick one up today!

If you have questions about the build process or suggestions/feedback about this article, feel free to let us know by contacting us. We look forward to hearing from you!

Until the next build …

~ f i N

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