SHAKA TUBE POWER HELP

[mrfirstime]

HI Guys

I have built the power part of the shaka tube and everything looked great.  When I measured  the dc voltage out it only registered as 2.8 volts or so.  I double checked the wiring and it all looked correct.  Is there something I've done wrong.  Here is a pic of it so far.  .

Linton

[petemoore]

  The traces/joints look like they were cooled by adding solder, never reached bonding/connecting temparatures.
  Clean parts is always a good preparation, vigorous rub on clean denim or lightly fine sandpapered then wiped off works.
  Hot tip is cooled by solder.
  Consider ways to break down very large heat-sinking joints [large thermal mass], use of leads above board work for me, be sure there is ample physical structure, other than that fairly short leads and connections is the goal.
  Make sure the right tip [I like flat screwdriver looking tip <1/8'' wide] is hot and tinned.
  Make sure all the parts are prepared as best possible, so the soldering will go well:
  Clean, fixed in place somehow [testclips, tape, bent around the edge...whatever so it doesn't move around and splash solder.
  Position the board/components so the iron tip has good access [preplanning what goes on the board first helps, for instance with IC sockets I work toward the ends from the middle, nothing worse than an IC socket pin that is between two others where the iron can't easily access around the 'other stuff'.
  Ok, hot, clean, freshly tinned iron touches a lead at a solder joint, it might take the second small touch of solder before the heat actually begins the 'fast transfer' process. Allow the heat to transfer for a short time before adding more, cold, solder...add more solder so the heat travels through it instead of the teeny touch point between wires which are only slightly heat conductive compared to having a little bit of solder wetting/enlarging greatly the heat transfer area.
  Don't use much more solder, only enough to make the structure structural, or to get it all the way around the joint [very small dabs with pauses, that way the joint doesn't get all the heat sucked out of it by heating lots of new, cold solder.
  I would go over every solder point on that board, then use DMM to check them.

[anchovie]

I'd like to suggest that you have one thread about this project. You're starting a new one with every enquiry that you have. Please also supply a link to the schematic that you are using - plenty of people like to help but it makes our lives easier if we don't have to go searching for diagrams ourselves.

[Paul Marossy]

I don't know why you are having this problem, but I did notice that the resistor to the left of the diodes is a 1/4 watt. It should be a 1 watt resistor. Does it get real hot? Also, did you use a 10 ohm for the aforementiond resistor?

[mrfirstime]

Sorry about the thread thing I didnt realize it worked like that it worked like that.

HI Paul

Yes it is a 10 ohm and I did ask the sales dude to make sure all the wattages were correct and no its not getting hot. I think Im gonna check the battery on my multi

thanks

[Paul Marossy]

Yes it is a 10 ohm and I did ask the sales dude to make sure all the wattages were correct and no its not getting hot. I think Im gonna check the battery on my multi

OK, was just a thought.

[mrfirstime]

I just discovered that I was using a 470k resistor instead of 470ohms.  I put the new ones in and I still get a strange voltage reading over the + - and bias out puts.  I am now reading 29V.  Is this right

[slacker]

How are you measuring it? If you're measuring with one probe on V+ and one on V- then 29 volts is about right. The power supply should give you +12 volts and  - 12 volts, or 24 volts if you measure between V+ and V-, without anything else attached the transformer or wallwart will put out more than it's rated voltage so 29 volts seems reasonable.
If you measure from ground to V+ and ground to V- you should get about +- 12 volts, again probably a bit higher with nothing attached.

If you measure from ground to bias it should go from +12 volts to -12 volts depending on where the pot is set.

[Paul Marossy]

Now you're in the ballpark. 

[mrfirstime]

Hey thanks

I was abit confused about how to read it but what you have told has sorted out and Im gonna proceed to the next step.

[GERRY_MAN]

I was having a similar problem also, I had a 10K instead of the 10ohm resistor on the power supply. Woops!!
The voltage now reads the same on my board at 29 Volts DC.

Thanks guys!!

-Gerry

[mrfirstime]

Great and hows the pedal working out.  Have you had any other problems

Linton