Bumble Bee No Effect

[BRGPollen]

Hello all,
         I am perplexed that I seem to have the same signal when bypassed as when engaged with my Bumble Bee.  To Preface, I am not one of the fx wizards here on the forum, however the Bumble Bee is my 13th (yes lucky # 13) pedal build.

        I have gone over all of the solder joints countless times, cleaning and reflowing anything that might be suspect.  I have checked all of the Emitter, Base and Collector pin outs for all three transistors until I am blue in the face.  I have replaced the Input and output leads twice, thinking that some how I might have a stray hair wire touching that was sending input to output.

        I always put the pcb's on the breadboard testing rig before I box them up.  The rig is powered by a 9volt battery and I have checked it's voltage.

        My question at this point is one seeking advice.  Should I go the rout of the audio probe or start looking at voltages next.  This is my first build that I have run into this problem.  

        Usually if I don't have signal, I break out the audio probe and see where the last point the audio is present and work from that.  This time there IS audio at the output, it is just the same as when the effect is not on.  To make sure I was hearing the circuit, I disconnected the input, switched the effect on and there was no output.  Thus, I have verified that the problem is not in the switching of my test rig.  Any Ideas?  I'm sure this will lead to a DUOH! moment.  But I look at it as a puzzle to be solved and a lesson to be learned.  Any help is appreciated.

"B"

Edit:          Jon, The Pots do not change anything at this point.  I am using Chromesphere's Russian germanium transistors (ufo style) for Q1 (Current = 547va Leakage = 36va HFE = 56.7) and Q2 (Current = 566va Leakage = 24va HFE = 60.2) and a Russian tophat for Q3 (Current = 1445va Leakage = 214va HFE = 136.7).  I am totally slammed with Daddy duties today but will get voltages tonight when I get the kiddo's down.  Thanks again for the direction.


EDIT #2    After a little time with my audio probe and my radio shack  multi-meter I am even more confused.

           Leaving the output connected to the test box out, no matter where I place the input probe I get the same signal (un-effected).  When I reversed the process and left the Input connected to the test rig same thing!   I also get audio when I probe the c6 electro! I thought being the first thing in line with the power that is a little odd! I doesn't matter whether I have power or not during these tests, I tested both ways.  That brings me to my next conundrum

          I tested a 9v battery this am & it read 8.7volts by the time I had finished all of the testing it read 7.46.  All of these numbers have to be wrong
          Q1: .561
                .563
                .563
          Q2: .553
                .562
                .655
          Q3 .732
               .739
               .766
"B"

[hammerheadmusicman]

It's probably not this, but, i have had some real issues with flux recently, i would make sure that you clean all flux off porperly, with some kind of alcohol, like IPA.. I was building up a tubescreamer recently and i fired it up, it didn't work, cleaned the flux off, and there it was!

Like, i said, this probably isn't the solution, but more of a tip for future reference..

Good Luck

George

[midwayfair]

Barrett, do the controls change the sound at all? Does the sustain pot lower the volume? Does the timbre pot change the tone? Does the sound shut off when the balance pot is fully counterclockwise?

We can at least narrow down where the problem exists.

Which transistors are you using? 313B?

And yes, I'd take voltages first and then audio probe -- every time there's a problem. Those will usually tell you more than forumites can. Plus the more information you have, the easier it is to say, "no that's not the solution."

[BRGPollen]

Jon, (and anyone for that matter)
          I have modified the original post to contain my current position in the Bumble Bee puzzle!
     Thanks again for looking at it!

"B"

[midwayfair]

Your voltages are way too low at the 9v connection, and your battery is draining: You almost certainly have a short in your power section. Could be a dead polarity protection diode, a busted electrolytic that's conducting ... something like that.

[BRGPollen]

Jon,
         Thanks for looking into this again.  So would replacing D2 and C6 be a good starting place?

"B"

[midwayfair]

Jon,
         Thanks for looking into this again.  So would replacing D2 and C6 be a good starting place?

"B"

If they're conducting/shorted, they're the most immediate culprits. Don't pull anything you don't have to. If you have a short from 9v to ground, then SOMETHING is shorting it, and it's not your soldering from the looks of the picture.

[BRGPollen]

Jon,
          So I replaced c6 and d2.  Same result.  Something odd that I didn't think to check until this morning is that I get 1v when I measure the -9v pad and grnd pad (next to the in and out on the boardP.  I'm pretty sure that I should have the same voltage as my battery there.  Does that sound weird to you?

"B"

[Bret608]

Hmm, that is strange! You should be getting the same voltage as your battery on the pad where the wire is soldered to the board, and 0 volts on the ground pad. Could a bad battery clip be involved? I wonder if you should check for continuity between the two terminals on your batter clip. Just a thought! I'm guessing there should be no continuity between the two but am not sure.

[electricstorm]

Was the battery you used a fresh battery? Possibly, if it was an old battery, it may have drained quickly while testing.

I haven't checked the Russian transistors, but are they PNP types? What are the part numbers for them?

Check the voltage of a fresh battery, attach the battery to the pedal and check the voltage again from the battery, then check the voltage at the junction of D2 and C6. They should be the same or at least very close. Do this with the pedal off and on. The voltage should not drop very much if at all. Also, you might want to check to see what the current draw from the battery is, this could tell you for sure if you have a short. Put your meter on DC Amps, plug your probes into correct sockets on meter for measuring amps, then place the meter in series with the negative line of the battery and adjust the meter for a reading It should be a few milliamps. What is the current draw?

If I calculated it right, your voltage at the base of Q1 should be around 7.4 volts and the base of Q2 should be around 4.2 volts.

Hope this helps in some way.

Jim

[BRGPollen]

Bret608
          I thought about the battery clip shorting and checked it before i ran the last set of numbers, & just to make sure there was no doubt in my rig again I tested another project with it (Rainy Day Dist) and all is as it should be!!  I appreciate any angle though.

Electricstorm
          I will get to that method in the next day or so.  Thank you for the idea.

Again thanks guys, I'll solve this puzzle yet.

B