Merman motorboating, oscilating

[Bluz]

Hey,  It'd been a while since I built a pedal.  So I decided I needed three (3) VFE overdrives.  Blues King, Pale Horse and the Merman.  I am having issues with the Merman.  The pedal works but with very low volume, drive etc.  And when I turn up the drive to full or off, it makes a motor boating type sound.  Any ideas?  Here's the voltages:
IC 1                       IC 2                        IC3
1  2.39   5  4.99      1  2.34    5  5.99      1  5.0     5  5.00
2  2.39   6  2.00      2  2.39    6  2.63      2  2.40   6  2.64
3  1.53   7  2.39      3  2.41    7  2.36      3  3.10   7  1.44
4  2.90   8  2.39      4  0         8  2.41      4  0.00   8  0.00
I was using an ONE Spot when checking voltages which it was putting out 9 volts.   I also checked the voltage of the switching board at V+  and it measured 5.00.  I am thinking this may be the problem???  Not sending 9v to the board?  Thanks for the help and advise!!! 

Thanks, Bluz.

[madbean]

Well, you've definitely identified the problem which is voltage related. But there's no way to know why unless we can see some pics of the build. That might provide a clue as to what's wrong. Also, all the usual - check soldering check for solder bridges, etc.

[Bluz]

Ok, so here in KY we had a LOT of rain.  Lake Cumberland/Wolf Creek Dam is at 753 feet.  Think that's a record.  I also had a flooded basement as well.  Built my house 20 years ago and first time ever.  Pumped out about 200 gallons of water.  So, I took some pics with my crappy camera.  It's very difficult to see the soldering side since the pots etc are mounted.  I am thinking it is the switching board.  Shouldn't it have 9v at V+ going out?  Thanks for the help!  Mike.

[Bluz]

Ok, feel like I am talking to myself since I just posted the pics....haha.  When I looked at the switching board after making the pics, I looked at the regulator LP 2950.  I ordered my components from mouser.  On the regulator I installed reads KY 5050.  So I looked on the shipping package from mouser and it reads LP 2950 and the other 2 regulators inside the package read KY 5050.  Would this be the problem?   I had one spare regulator LM78L05 from a previous build and used it in the Pale Horse and it works just fine, may look to see if I've got another one.  Mike.

[fair.child]

That 4u7 on switching board is killing me. It works but you should consider use Low ESR cap for the next build.

KY5050 is correct LP2950. Your switching board looks fine to me. The problem could be on your main board.

[Bluz]

The cap is one I had on hand and I wanted to use up some components.  I'll use a low ESR on the next one.  Anyways, I did find a couple resistors I used that are 1/4 watt and the leads are touching the "body" of the itself. would this cause a short or any issues?  I am gonna redo them or at least make some space between.  I used 1/4 watts because I have a boat load of them and need to use some up, maybe should of bought some 1/8 watt resistors.  Thanks.

[Bluz]

What should the output voltage be on the switching board?  Mike

[Bluz]

Well, got home from work an finally had time to work on this issue.  Ive got the correct voltage reading on the IC's.  It is an issue with the switching board.  I am trying to track down the component.  I will also finish the Blues King in the morning....hopefully without issues.  The problem with the switching board is it now doesn't toggle between on/off, no power to LED.  Anyone with suggestions?  I have not done anything to the switch board at all, just rewired the connection between the two boards with better quality wire.  I'm sure its a short in the wire?

[Bluz]

I have checked voltage on the switching board, there is 9v on everything I check.  Any help or suggestions would be greatly appreciated.  The foot switch is working properly too.

[Bluz]

Problem solved!!!!!  It was the switching board, a bad component.  Just finished up the Blues King as well.  All 3 will be on the pedal board and using with our praise and worship band.........

[destro]

Glad you figured it out! I'm in Lexington. Yeah, we've had quite a bit of rain consistently. It's like Seattle. ha! I've got a sump pump in each corner of my basement after having experienced flooded basement in 06....been dry since.

[zgrav]

what component was bad on your switching board?