HELP Wiring Beesneez BV12 to D-U67 circuit.

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FarisElek

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Joined
Oct 26, 2019
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509
Hello. I've had the Beesneez BV12 mis-wired to the D-U67 for months now. My caridoid seemed good, figure 8 was dull, and omni was weak and didn't have enough low end. I know it's from because my polar patterns didn't sound right. When I altered the wiring today to another configuration, Cardioid sounded even better, Figure 8 no longer was dull, and Omni is now dull and has no high end, and they all now contain a high-pitched transformer buzz.

The Beesneez BV12 doesn't have a datasheet and what I got from Ben doesn't really explain to me how to wire it to this circuit. It merely shows which pins are secondary, primary, and tertiary. I compared the T67 to the Beesneez BV12 and attempted to match primary, secondary, and tertiary windings and the side of the transformer that winding is on to the circuit. I think I'm close, but I think I have some of the sides swapped simply because it doesn't work quite the same way as the Tab Funkenwork.

If there is anyone out there familiar with this circuit or transformer, please help me. I am so close.

I've attached a picture that has the drawing Ben sent me, and the circuit.

If you need any info from me, just tell me how to record the data and I've got it covered.


Thank you,
Ryan

 

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Here is a JPEG version of the photo.
 

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This was confusing for me to figure out as well.  These are my notes, hopefully you can figure it out!

I translated the german to the vintagemicrophonepcb layout.  I used a moby transformer.
 

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I've done a ton of studying of other transformer wiring. Unfortunately, It didn't help. I just don't know how to find out what primary, secondary, and tertiary pins are audio in/out, and where they're supposed to go on the PCB.  None of the other transformers are mentioned in this way in there wiring diagrams.

Thank you reaching out though.
 
Pull up the schematic, my notes show how the pcb pads relate back to the schematic and how it is all hooked up. There are 6 pads on the pcb and 6 pins in his picture.

Primary is audio into the transformer, secondary is out from it.  Tertiary is the feedback for the eq in the mic.  The phase is relational, meaning it doesn’t matter which primary goes to which primary pin, but you need to have it the same from then on or you’ll flip the phase, and I would assume the feedback part would not work right.
 
I’m not 100% that I understand. But I think t11 + t44 are primary, t1010 + t77 are secondary, and t1212 + t55 are tertiary. From there I made The primary from one side of the transformer to t11, and the other side to t44, and did the same for the others.

Does this sound correct?

Ryan
 
I just tried the configuration I mentioned above and it yields the best results I've gotten, but it still have this weird problem. the Figure 8 is noticeably duller sounding. The "air" disappears, and the omni feels weak. This is the case whether you're standing far from the mic or not.

It it seems that I've wired it correctly. Could it be that it is incorrectly wired to itself? Is there a resistance each winding should be at? How do I check?

Update: I just checked and can say with certainty that the backside of Figure 8 and Omni sounds good/like the frontside of Cardioid.

What is happening!?

And in your notes, what do the roman numerals mean? I thought primary went to ground and C9, but you have III written there.


Ryan

 
Interesting notes on my tranformer:

1) primary appears to be 1.68k resistance
2) Secondary is 49.5R
3) tertiary is 73R

when I send in 19.22VDC into the one primary "primary"

I get

1) 19.22vdc out the other primary
2)  .026 out the secondary
3) .010 out the tertiary.

I'm going to take a wild guess and say the transformer is either faulty, or that it's completely wired wrong to itself.

 
FarisElek said:
Interesting notes on my tranformer:

1) primary appears to be 1.68k resistance
2) Secondary is 49.5R
3) tertiary is 73R

when I send in 19.22VDC into the one primary "primary"

I get

1) 19.22vdc out the other primary
2)  .026 out the secondary
3) .010 out the tertiary.

I'm going to take a wild guess and say the transformer is either faulty, or that it's completely wired wrong to itself.
Hey, just a double check. Are you sending 19.22 VDC or Ac? I hope you made a typo
 
I did not. I’ve understood my mistake  :(

I already bought a new transformer. That has more info on it so I can rule out the transformer as being a problem. It could have been something else all along.
Now that I actually know how to test the Beesneez transformer I’ll test it right and hopefully I didn’t break it. Maybe I can use it on another build in the future.
 
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