Studer 169 EQ in API 500 format

[PatchDog]

Hey DIY friends! I'm a bit new to DIY without instructions and so on. With that said, I bought an LED holder/LED with built in resistor.

Is there a way to connect it to this F2UEE switch? The other threads were a bit fuzzy answering this question.

The unit works flawlessly other than that.

Thank you!
Mike

I bought the DPDT version of that switch (You have the DPST) and I just bent the last 6 pins legs to fit on the board, then I could use the extra throw to send power to the LED. You can see it here:

 

[mooksnook]

Hey gang, would someone please post a link to a toggle switch that's suitable for the frequency selection?

From what I've seen it seems to be working with a double pole switch for both hi and low switch?

All the best

 

[mooksnook]

After some months of slowly putting this EQ together I am finally done! Built myself a pair with LED's installed, Neutriks and Capi OA10 opamps.
They sound fantastic!!

 

[boombipbass]

wow! how cool is this, did your friend actually made it? i want to for sure!
but the files on adjusting the filters and such to my own likings can;t be found anymore
any chance in re-uploading those?

would be highly appreciated

 

[mooksnook]

wow! how cool is this, did your friend actually made it? i want to for sure!
but the files on adjusting the filters and such to my own likings can;t be found anymore
any chance in re-uploading those?

would be highly appreciated

All info that is needed can be found in this thread. You need to read all pages. I've spent hours reading through this thread and learned so much. Part of the fun!

 

[mooksnook]

Hello all future DIYers. I have compiled a Google drive folder for everyone to make things way more simple.
This is hours upon hours of research for a beginner-mid experienced DIY guy like me.

The BOM I've made is for neutrik in use and LED.

https://drive.google.com/drive/folders/1qycG9mJdc9bn-qeUScphqYrZyHtNWb7x

 

[mooksnook]

wow! how cool is this, did your friend actually made it? i want to for sure!
but the files on adjusting the filters and such to my own likings can;t be found anymore
any chance in re-uploading those?

would be highly appreciated

https://drive.google.com/drive/folders/1qycG9mJdc9bn-qeUScphqYrZyHtNWb7x

 

[yayastudios]

Dumb question but I'm brand new to this hobby. I'm currently building two of the Studer 169 EQs and it calls for a 1k6 resistor, all I currently have are 1k5 resistors. Would this be fine to substitute without causing potential problems to the circuit and/or functionality?

 

[soulsonic]

Dumb question but I'm brand new to this hobby. I'm currently building two of the Studer 169 EQs and it calls for a 1k6 resistor, all I currently have are 1k5 resistors. Would this be fine to substitute without causing potential problems to the circuit and/or functionality?

If you're not trying for Swiss precision, 1K5 should be fine.

 

[yayastudios]

I was looking at the BOM and it lists C21 and C22 as 100nF, but does not say whether they need to be excluded if you are using a DOA. I know the other parts that fit into the DOA slot like the 22p capacitor and the IC socket are only to be used if you don't plan on using a DOA. My question is do I need to install the 100nF capacitator even if I plan on using a DOA or is this one of the components that can also be excluded if I'm using a DOA. The BOM wasn't clear on this.

 

[dmp]

I think those are on the power rails and should be included. Check the schematic. I don't think there are any parts that need to be excluded to run the DOA. You can have everything installed and run either type

 

[mooksnook]

I was looking at the BOM and it lists C21 and C22 as 100nF, but does not say whether they need to be excluded if you are using a DOA. I know the other parts that fit into the DOA slot like the 22p capacitor and the IC socket are only to be used if you don't plan on using a DOA. My question is do I need to install the 100nF capacitator even if I plan on using a DOA or is this one of the components that can also be excluded if I'm using a DOA. The BOM wasn't clear on this.

When using DOA you should skip C16, C17, U2 and U3. I did just that and mine work perfectly.

I made my own Google drive folder with BOM for a more simple approach. Follow that and you should be fine.

 

[mooksnook]

I was looking at the BOM and it lists C21 and C22 as 100nF, but does not say whether they need to be excluded if you are using a DOA. I know the other parts that fit into the DOA slot like the 22p capacitor and the IC socket are only to be used if you don't plan on using a DOA. My question is do I need to install the 100nF capacitator even if I plan on using a DOA or is this one of the components that can also be excluded if I'm using a DOA. The BOM wasn't clear on this.

https://drive.google.com/drive/folders/1qycG9mJdc9bn-qeUScphqYrZyHtNWb7x

 

[soulsonic]

I have not been able to find any explanation for why the original layout called for dual gang pots wired in parallel where a single gang would work. Is it just to be specific to the Omeg center detent pots that were available at the time?

 

[MidnightArrakis]

Cheers @DarkSky, as you suspected all went well, no mods required.

Everything's tracking very well and the detented gain pots are a massive improvement as I tend to use these in stereo most of the time.

Guess it's time to add some pics to the thread then. The panels still only have the drill guide on there, will finish them off later.

[Guess it's time to add some pics to the thread] -- Even though I'm about a year late in joining this party, I just wanted to add a comment here saying.....based upon what I am seeing here with your solder-joints, you either don't have your soldering-iron hot enough or you're not leaving your soldering-iron on the component-pins and PCB-pads long enough to heat them up properly to adequately melt and flow the solder.....or, both.

The end result of these types of solder-joints can range from intermittent operation, scratchy-noise when rotating the pots or even a break in the signal not being able to pass-thru. I really hate to say it, but.....these are all very low-quality solder-joints!!!




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[MidnightArrakis]

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