Bo Hansen DI layout

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thewotan said:
First of all, thanks to everybody for your comments!

I checked all the components with the multimeter and seemed OK, so after that I rechecked the board for any bad soldering and found a couple of spots that seemed strange, so I tried to resolder only to find that the pad from the PCB was gone :-\ 

Don't throw that board away, you can just run a jumper wire from that component leg to the next one and make it work.

I lost a trace on one of mine, too. Those boards seem a little delicate.
 
thewotan said:
I had my iron at around 300º (or that was my cheap soldering station marked...). Was that too hot and that was what caused the pads to go away?

That's really too hot for 98% of the work that's done in this forum.

For these type of boards and small components I use a 11w soldering iron.
I would not go over 30watts for any kind of this work, and thats even a bit too much sometimes.

index.php



Like Ricardus said, a broken or damaged solder pad or trace is easily fixed with wire or a jumper.



 

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I was so bummed it wasn't working and then so happy it did that I didn't think about running a wire from the leg of the component!

I supposed that 300ºC was too high, but it was having trouble melting at (supposedly) 230ºC. Again, it's a cheap station. I hope to improve on that department soon enough.

Here are the pics! If you have a "Worst Soldered PCB of the Year" contest in the forum, let me know so I can submit this ;D ;D
 

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Wow! Only 1 pic per post?


Here it is mounted on the base of the box. I'm waiting for some stepped drill bits to ruin the front trying to make the holes  ;D

It's a big box for the OEP transformer, but I thought that I could fit two cards inside to make a stereo one
 

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thewotan said:
Here are the pics! If you have a "Worst Soldered PCB of the Year" contest in the forum, let me know so I can submit this ;D ;D

Don't be so hard on yourself. There's at least one or two good joints on that board!  :D

Is that the "bad" board you mentioned first? Because I think I see the missing solder pad.

A bunch of those joints need to be reflowed and the leads trimmed shorter.

I've built DIs with all three transformers (and some with other transformers not supported on the board) and feel I can say you'll be very happy with the OEP.
 
Ricardus said:
Don't be so hard on yourself. There's at least one or two good joints on that board!  :D

Hahahahaha! That's I start, I guess!

Yeah, I have to clip the leads and clean it a bit better. I thought about reflowing it but as it is working maybe it's better to leave it be :D

Good to know about the transformers! Truth to be told, it sounds pretty amazing on my bass with the OEP, so I might use that money on making a preamp if I ever get locked down at home with no possibility of going out...  ???

Thanks for your pointers, Ricardus!
 
Guilty of replying to an old thread apologies in advance.  I can't find anyone with these PCBs available anywhere.  Does anyone fabricate them anymore?
 
parkay909 said:
Guilty of replying to an old thread apologies in advance.  I can't find anyone with these PCBs available anywhere.  Does anyone fabricate them anymore?

This thread is ongoing because it's a pretty popular build.

Contact Volker:

Bo Hansén Active DI-Box 1975:
PCB: EUR 6,50 each + shipping + VAT where applicable
Haufe ST8456 transformer: EUR 33,50 each + shipping + VAT where applicable
(other transformers are possible but need to be purchased elsewhere)

contact sales[at]51xAudio.com if you have any interest.
 
parkay909 said:
Guilty of replying to an old thread apologies in advance.  I can't find anyone with these PCBs available anywhere.  Does anyone fabricate them anymore?

Hello Parkay,
welcome to the forum. Hope you have a great time here.

You don't have to apology for writing in an old thread, in GroupDIY no one has any problems with threads continuing some years after... No one will be upset with you for reviving any old thread. But in this case this is not even an old thread, this is an active project and active thread.

On the other hand there's something that is in the forum rules, "Search and read before posting", and not doing that will rightfully upset people.
The source for the PCB's is clearly stated in the FIRST post of this thread.
So in the future please read a little more and have a bit more effort before posting.

Hope you buy the PCB's and complete this project, if you do so , let us know how it goes.
 
Just wanted to say thank you to Bo Hansen for this awesome design and thank Volker for keeping the PCB available.

I've never considered myself a DIYer with electronics but I wanted to change that. This was my first project and although it did not work at first, I was able to determine from previous posters that I installed my transistors backward. I used 2N4401 and 2N4403 but overlooked Bo's note about rotating one half turn. Swapped those around and it sounds beautiful!

Thank you again to everyone involved here.
 
rounder said:
This was my first project and although it did not work at first, I was able to determine from previous posters that I installed my transistors backward. I used 2N4401 and 2N4403 but overlooked Bo's note about rotating one half turn. Swapped those around and it sounds beautiful!

Thank you again to everyone involved here.

Welcome to the forum Rounder, hope you firsr post is the first of many.

Congrats also to be able to finish your project and troubleshooting by reading here before posting.
Most new members overlook the wealth of knowledge and common shared experience that is already in the projects threads

best regards
 
Hello There!

I have read about the Bo Hansen Di Box a lot in this forum an now I am starting to build one on my own.

I was thinking to add the Pad-Mod to my build and came up with a question:

Is it really necessary to use a DPDT switch? Wouldn't a single poled one also work ?

Thanks for the reply Bo. Is this diagram correct?

Basically use DPDT SWITCH (ON-OFF-ON) wired so....

I accidentally bought a SPDT (on-off-on) switch and came up with this diagram:

Pad.png
So will this work or am I missing something?

J.Z
 
Hello There!

I have read about the Bo Hansen Di Box a lot in this forum an now I am starting to build one on my own.

I was thinking to add the Pad-Mod to my build and came up with a question:

Is it really necessary to use a DPDT switch? Wouldn't a single poled one also work ?



I accidentally bought a SPDT (on-off-on) switch and came up with this diagram:

View attachment 80637
So will this work or am I missing something?

J.Z
That wiring seems basically right. I think the switch is upside down though. There is another drawing way back in the thread that I used as a reference. And yes, a SPDT (on off on) is what is used.

I think the way you have that wired would be:

UP -20 dB
Middle -10 dB
Down 0 dB
 

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Fo those who have used the Hammond 1455N1201 enclosure how are you mounting the PC board? I see it has channels to hold the standoff screws on the sides but they are too narrow for the board. I'm hoping to do something more elegant than having 4 screw heads protruding from the bottom.

 
Fo those who have used the Hammond 1455N1201 enclosure how are you mounting the PC board? I see it has channels to hold the standoff screws on the sides but they are too narrow for the board. I'm hoping to do something more elegant than having 4 screw heads protruding from the bottom.

I made 6 of them with that case and just epoxied the standoffs to the inside of the base of the enclosure. These pics are actually from a different enclosure, but the idea is the same.
 

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Fo those who have used the Hammond 1455N1201 enclosure how are you mounting the PC board? I see it has channels to hold the standoff screws on the sides but they are too narrow for the board. I'm hoping to do something more elegant than having 4 screw heads protruding from the bottom.

Here's one using the Hammond where I used a Carnhill trafo and mounted it off the PCB. You can see the epoxied standoffs.
 

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