Part identification help?

[Toastman]

Hello, well I recently acquired Titan II PCB with the BOM list. And I need some help with the part identification.

The C5 capacitor doesn't add up to BOM. It should be electrolytic. And I don't know which one is C100 and C101.

There are maybe some more other inconsistencies. If anyone could spot them and help me fix them...

Thanks for any help.

 

[Harry Klippton]

The silkscreen for C5 shows an electrolytic laying on its side

 

[Toastman]

The silkscreen for C5 shows an electrolytic laying on its side

Yes, and it should be 100nF by the BOM. Which Is wrong I think...The C4 is 47uF, which is usually electrolytic

 

[Harry Klippton]

What is this BOM? it's really hard to look at

 

[Fama]

Are you sure the BOM is for this board? I don't see FB1 or FB2 on the BOM either.

 

[mybud]

Are you sure the BOM is for this board? I don't see FB1 or FB2 on the BOM either.

It doesn't correspond with the PPCB Titania 2 board as far as I can see.

 

[Harry Klippton]

My guess is that PCB guitar mania and/or LLM are involved here

 

[mybud]

My guess is that PCB guitar mania and/or LLM are involved here

Where's the 'fear and trembling' icon when you need it most?

 

[Toastman]

Alright, so I tracked down the PCB, and it was corresponding to the Titania 2, I had to bypass the FB1, no problem...the C4 and C5 were interchanged...

Well it works, there's not a lot of distortion, plenty of volume. So I accidentally made a new pedal

This isn't normal for Titan 2 fuzz am I right?
Also removing the Q1 does nothing, which I suppose isn't correct.

 

[Toastman]

Theoretically what would happen if I removed the Q1? If it worked correctly

 

[jwin615]

Theoretically what would happen if I removed the Q1? If it worked correctly

You would be bypassing the first gain stage and passing audio to the second gain stage through a 1meg resistor. So yeah. Cleanish boost.

 

[Toastman]

Hello again, so i menaged to get it to work, C4,C5 were intercharged. And also R2 and R3. there is miniumum hum, its sounds really good. But unfortunately there is a little to no sweep to the gain knob. Like gain from 70 to 100%. Is it normal to this style of circuit? What part of the circuit should i focus on? Thanks very much

 

[jwin615]

Did you remove Q1?

 

[Toastman]

Did you remove Q1

No, it now works with all three transistors. Removing one kills the signal.

The mistake was, that the R2 was 1M and R3 was 1k ohms. It was mislabeled on the PCB...

 

[Toastman]

It also sounds darker on lower gain

 

[jwin615]

It was mislabeled on the PCB...

I highly doubt this.
I'm a bit tied up at the moment.
Could you post clear photos of you build, both sides of the PCB as well as where you have different/changed values vs the schematic? I'll give it a look tonight and it will give others a chance to be d their brain around it.

 

[Toastman]

Alright, sending all. The soldering looks more messy on the picture than in real...

I had the BOM (The excel sheet) I traced the PCB with my limited knowledge.
Well the C5 is mislabeled C4, and the R3 and R2 were interchanged in the PCB opposed to the BOM. The BOM isn't exactly to this PCB, but it was close enough.

Everything else works and it sounds great, the gain knob doesn't do that much. It's straight up higher gain. Cleans up nicely with volume knob.

 

[swelchy]

what brand pcb is this from.... So I can avoid it

 

[Toastman]

No Brand, DIY

 

[jwin615]