Doodlebug - USB Isolator
Jan 27, 2015 at 12:18 AM Post #256 of 305
  jdslabs do an 8cm mini USB, if that's any help

 
Egad, that is ridiculous on the other end of the spectrum. Still, dirt cheap, so may be an option.
 
 
Hey beefy, happy Australia day mate :wink:

 
Heya Dingo! Australia, f'yeah! If you don't love it, leave! Oh wait......
 
Jan 27, 2015 at 12:34 AM Post #257 of 305
 
You nailed it, Beefy.  I've been looking for one, but haven't found any that are reasonably priced.  If someone could point me in a good direction, I'll start including them in the kits.
 
P.S. Monoprice was the first place I looked.  I can't find anything under 1.5 feet.  When I've found the shorter ones, they're expensive and no volume discount.

 
1.5 feet is the perfect length for me, i use these from my isolators to DAC's.  The larger 24 gauge power wiring is what initially caught my interest, they also include a ferrite and gold plated connectors for a couple of $$'s, what more could you want
normal_smile .gif

 
http://www.monoprice.com/Product?c_id=103&cp_id=10303&cs_id=1030302&p_id=5446&seq=1&format=2
 
Jan 27, 2015 at 7:42 AM Post #258 of 305
That one looks pretty good.  However, I have some questions:
 
1. What is meant by "28/24AWG?"
2. Would you guys prefer white or black?
3. I've also found some black ones that just say they're 28AWG, but they're only 1 foot long.
 
Is the ferrite core important in this application since the DoodleBug performs complete isolation?
 
Jan 27, 2015 at 9:25 AM Post #259 of 305
  That one looks pretty good.  However, I have some questions:
 
1. What is meant by "28/24AWG?"
2. Would you guys prefer white or black?
3. I've also found some black ones that just say they're 28AWG, but they're only 1 foot long.
 
Is the ferrite core important in this application since the DoodleBug performs complete isolation?

 
1) 28AWG wiring for the two data lines, and heavier 24AWG wiring for the two power lines.  Same format as the Belken cable i also use, e.g.
 

 
2) Black or people will think its made by Apple
rolleyes.gif

 
3) Ferrite probably does nothing, but cant do any harm IMO.
 
Mar 8, 2015 at 3:18 PM Post #260 of 305
Hey guys. Is this an appropriate place to post troubleshooting questions about my recent doodlebug build?

I can't get my computer or my phone to detect my ODAC through it. I previously used my Note 4 through an OTG cable straight in to the ODAC.

the psu section seems fine and I've tuned the voltage between 5-5.25V in various tests. I can pick up 5.1V coming from my phone to the main chip.

When I plug the mini usb cable in I get continuity between R2 and R3 through the chip. the 6 pins connected to C3 and C8 give 3.36V relative to their respective grounds. I don't read any DC at R2 or R3 but I get about 4V at R5 and 3.6V at R4...They're supposed to be data lines though..
 
Mar 8, 2015 at 3:45 PM Post #261 of 305
Hey guys. Is this an appropriate place to post troubleshooting questions about my recent doodlebug build?

I can't get my computer or my phone to detect my ODAC through it. I previously used my Note 4 through an OTG cable straight in to the ODAC.

the psu section seems fine and I've tuned the voltage between 5-5.25V in various tests. I can pick up 5.1V coming from my phone to the main chip.

When I plug the mini usb cable in I get continuity between R2 and R3 through the chip. the 6 pins connected to C3 and C8 give 3.36V relative to their respective grounds. I don't read any DC at R2 or R3 but I get about 4V at R5 and 3.6V at R4...They're supposed to be data lines though..


Pic?  We might be able to spot something obvious.
 
Mar 8, 2015 at 5:20 PM Post #264 of 305
the soldering isn't as neat as I'd have liked :hushed:

That's OK - we bare all around here.  It's the price in asking for help.
wink.gif

 
The DoodleBug has tremendous ground planes, so it is difficult to solder some of the ground connections.  Still, I'd say your PCB would benefit from some re-flowing over the entire PCB.  Use some good flux to help the heat transfer.  Messiness from flux can be cleaned quite easily.  Messiness from solder can mean the project won't work.  It looks like you may not have the pin next to R2 soldered at all.  Photos can be deceiving, though.  I half expected that you may have soldered the ADuM chip in backwards, but everything looks OK from a parts standpoint.
 
The ADuM chip could stand to have its pins rolled with the soldering iron - as described here in the 3rd and 4th paragraphs and pics on this webpage:
http://diyforums.org/Doodlebug/DoodleBugsolder.php .  Also, your photo doesn't show the pins from the mini-USB jack.  If those look similar, clean them up and give them a roll to finish off the pins.  Take the Wima capacitor out of there for the time being, if you have to.  The other chips and through parts - same thing - try to up the heat with more flux and get that solder smooth.  What you need is high temperature, but don't leave it on the joint too long.  If the solder doesn't melt right away, all you're doing is getting the ground planes hotter and you could burn the PCB.  This may be difficult on the pins connected to the ground plane, but there's no reason not to get all the other joints looking smooth and liquid-ey.
 
Finish up with some 90%+ alcohol to clean off the flux you use.  Let us know if you need recommendations on good flux and solder.  Again, this is described on the DoodleBug website at the same page mentioned above. 
 
Mar 8, 2015 at 6:13 PM Post #266 of 305
I bought a 1mm tip especially but my solder is probably too thick. I don't have a flux pen either. I did find it difficult to solder ground connections even with my iron on full heat

 
You'd probably want a thicker tip for better heat transfer. Most soldering is done without sticking the solder directly onto the soldering iron, but heating the part and letting the solder flow into the direction of the heat. Took me a lot of amateurish attempts to understand that concept of fluid dynamics.
 
Flux also helps the solder to flow better, and it has made soldering so much easier.
 
Mar 9, 2015 at 7:52 AM Post #267 of 305
My two cents...

 
Heat the board, not the component.
I just use a Weller WES51 with a standard tip at 550 to 600 degrees.

 
Another thing I noticed was that if you are using a device for the first time
or have just reloaded your computer, you may need to directly connect your
device to the computer before it will be recognized. Subsequently, it will
work properly through the Doodlebug.
 
May 13, 2015 at 10:38 PM Post #270 of 305
 
  Any one else built a DoodleBug?  Have experiences to share?  Pics to post?

I'm looking at building one.  I have a triad 12v unregulated wallwart.  Will it be safe to use?

 
If that's 12V DC, then yes.  If 12V AC, then it may be too much.
 

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