Red Llama Debug

[Kearns892]

Could use some help on this.
- Red Llama
-I get signal, but no OD, just a lot of hiss.
-I'm using the schematic from Beavis Audio.
http://www.beavisaudio.com/bboard/projects/bbp_RedLlama.pdf
While I am breadboarding this, I'm only using the schematic, not the Breadboard layout. I also noticed a discrepancy between the Breadboard layout and the schematic, the layout does not have voltage going to pin 5 of the IC like the schematic does. I put a jumper going to pin 5 like in the schematic.
-No modifications, all subs are caps with values within the tolerance of the original so they should be fine.

- Battery Voltage = 8.09v
- IC voltage
pin 1=5.00v
pin 2=0.00v
pin 3=5.00v
pin 4=0.00v
pin 5=5.00v
pin 6=0.00v
pin 7=5.00v
pin 8=0.00v
pin 9=2.06v
pin 10=2.12v
pin 11=5.00v
pin 12=0.00v
pin 13=0.00v
pin 14=2.04v
pin 15=2.12v
pin 16=0.00v

I searched but couldn't find a list of correct voltages. If any one has that it would be pretty helpful.
thanks

[slacker]

Your voltages look OK.

There's a couple of things that look wrong on the layout. The black wire from the volume pot looks like it's connected to +9 volts not ground. More importantly the 100uF cap (C1 on the schematic) is missing I don't think the circuit will work properly without that.

[Kearns892]

I didn't even notice the black wire on the volume pot, I have mine connected to ground though.
I did omit D1 and C1 due to the comment that they are only filtering components and are not necessary, I will add a 100uf cap there in a minute, have to go mow right now though.  Thanks for the prompt reply and giving me a place to start.

[Kearns892]

Added the C1 Cap, had to plug into the same hole as the 1k resistor (R1) and no noticeable change. Still a lot of hum and no drive.
I would trace it with an audio probe, but I have to admit I don't understand how the IC works and wouldn't know how to trace once I hit that.
Suggestions?

[Kearns892]

Well, I took each part off the bread board and tested it, all fine. I'm going to try rebuilding it from the ground up.

[Kearns892]

Rebuit it, still having problems. I used an audio probe and lose signal at the ends of R5, C5, C6, and Pin 10. I used a continuity tester to make sure all connections were good, and I checked the R value which measures right under 1M ohm, but I don't have the ability to test caps on my DMM, but I double checked the codes.
Suggestions? I've been stuck here for a while.

[SlashLP97]

Are you sure the 10uF cap is placed in the correct polarity? (Assuming you are using an electrolytic)

[tiges_ tendres]

Is this one of those pedals where it matters whether you use a buffered or unbuffered version of the IC?

Also, this effect draws a lot of current, you might want to try a fresh battery.

[Ripthorn]

My first time building this, I used a buffered chip and it hissed and sounded nastier than all nastiness.  Popped in an unbuffered chip and away I went.

[Kearns892]

Chip is UBE, 10 uF cap has the the positive side connecting to pin 10 and negative connecting to Volume Pot, looking for fresh 9 volt...

[geertjacobs]

Popped in an unbuffered chip and away I went.

Same here, got mine running last week with the correct chip.
I used this layout from GaussMarkov.

Kearns892,
Are the values of R5, C5, C4 ok?
Is your purple wire connected ok?
If that is ok too, maybe try another IC or rewire your breadboard to use another U1x section instead of U1b.

[Kearns892]

I'm thinking this may be a chip problem, I understood I needed an non-buffered chip, so I think I would have bought one like that, but it was just one part of a large order, I easily could have selected the wrong chip. The chip is  a TI CD4049UBE, there is another number on the chip, honestly not sure what this one is but reads, 7ACTCKM E4. Is there something in one of those codes that will tell me for sure I am dealing with a non-buffered unit? I don't have a chip I know is non-buffered to "pop in" and check it with.
If I've spent all these hours debugging and this ends up being the problem I will be very frustrated.
Thanks again though.

[geertjacobs]

74xxx is another name for the family of logic chips.
If it says UBE, it's ok.

Please take note that these CMOS chips are VERY sensitive to static, it could be that one of the sections (U1b) is already damaged by static electricity.
You can eliminate this by using another part of the chip or by using another chip.

[MikeH]

Silly question:  Did you perhaps mix up the pots?  And issues of no gain/od could come from using the 10K for gain and the 1M for volume.

[Kearns892]

I tried two different chips to no avail, and I checked the pot values. I did look at the invoice of my order form and it states that the chip is "CD4049 - Hex/ Buffer/ Converter" So I suppose I bought the wrong one. I took it off my breadboard for now, but I'll be sure to get an unbuffered one with my next order, thanks a lot guys.

[slacker]

the chip is "CD4049 - Hex/ Buffer/ Converter"

That doesn't mean it's a buffered chip, CD4049s are used as buffers in logic circuits that's why it's called that.
If it's a CD4049UBE then it should work as far as I know.

[MikeH]

Slacker is right- I'd look into something not being connected right (audio probe and continuity checker are your best debugging pals).  Does the gain pot have any effect, or does it just do nothing?

[Kearns892]

Dang. Sorry guys, I saw that and reluctantly dismantled it from my breadboard. No since rebuilding it now though in a few days I'll be without my soldering iron or anything really for about 2 months.

Thanks so much for all the help. If nothing else I've learned a lot and I'm sure it will come into play whenever I have time to rebuild this.