Death by Audio Germanium Filter

That's a start. Looks easy to trace. MP10B NPN Germaniums, decent quality components.

 
jesuscrisp said:
Yep, that very much looks like it's a SHO boosting some sort of fuzz! If you can finish it, that would be cool!
Click to expand...
I don't know, I've never traced a pedal before and I have no idea how PCBs work, this is all guesswork. Can't even tell if this makes sense.

Looks like there are two diodes for the BS170. The transistors should be in a Darlington pair.
I'll see what I can do, it's not like I have a life or anything to do this Saturday night.
 
You're doing great Andare!
Do take a break if you need to.

I was tracing the Vong Filterung and had to put it down for a ... month, or more already. The multiple switches were messing me up a bit (HPF-off, LPF-port, 180º-phase, Boost) and then there's the XLR out being pre-boost ... I was so close to finishing, but just had to take a break and get some other stuff done. Been dreading going back to it, but go back I shall, and soon. -ish.


Perhaps trace from the output backwards to familiar territory.
 
Feral Feline said:
You're doing great Andare!
Do take a break if you need to.

I was tracing the Vong Filterung and had to put it down for a ... month, or more already. The multiple switches were messing me up a bit (HPF-off, LPF-port, 180º-phase, Boost) and then there's the XLR out being pre-boost ... I was so close to finishing, but just had to take a break and get some other stuff done. Been dreading going back to it, but go back I shall, and soon. -ish.


Perhaps trace from the output backwards to familiar territory.
Click to expand...
It would help if I knew how circuits and PCBs work. A great opportunity to learn that stuff!
 
Looks like you're using DIYLC to map out the schematic. That's what I'm using, too.

Couple suggestions from a fellow amateur tracer...

Sometimes you need to have schematic pathways cross each other when they're NOT connected, so for stuff that IS connected, try putting a black-dot and have the path that isn't connected route next to where there's a connection black-dot. It's tedious putting in all the black dots, but makes for a more clear schematic.​

I read somewhere that some people producing schematics will never have more than three paths intersect at one point, so if you see a "T" on the schematic, you know they're connected. If you see a "+", however, you know the paths are NOT connected. Lots of people use various methods to differentiate the connections vs non-connections such as having a broken line "___ | ___" or having a dip "U" or hump "_∩_" "∈" "∋".​

Personally, I've found it's best to just have the dots. As for only having "T"s vs "+", the latter looks cleaner but gotta make sure to have those connection dots.


Here's a circuit snippet from a project I'm working on, the "BuzzBox" (2xBazzFuss) portion of it, reworked a couple of ways:

Bearded Clam Snippet.png

The two snippets above are identical, electrically, if the version to the right has D1, C5, Q1's Collector and R9 ALL connected at the "+", etc...


Here's how I'd handle a crossed path, if and where possible: Schematic-snippet crossing paths.png

"R20" and "C? 2µ2" need to cross the emitter of Q1, so I used a mix of grounding methods. However, since there's dots, I could just cross it:


Schematic snippet crossed.png



Best advice I read was that a schematic is meant to convey information; If a schematic leaves a viewer scratching their head for any reason, is unclear in any way, then it should be adjusted to be concise and clear.



Have fun with the rest of your trace!
 
Feral Feline said:
Looks like you're using DIYLC to map out the schematic. That's what I'm using, too.

Couple suggestions from a fellow amateur tracer...

Sometimes you need to have schematic pathways cross each other when they're NOT connected, so for stuff that IS connected, try putting a black-dot and have the path that isn't connected route next to where there's a connection black-dot. It's tedious putting in all the black dots, but makes for a more clear schematic.​

I read somewhere that some people producing schematics will never have more than three paths intersect at one point, so if you see a "T" on the schematic, you know they're connected. If you see a "+", however, you know the paths are NOT connected. Lots of people use various methods to differentiate the connections vs non-connections such as having a broken line "___ | ___" or having a dip "U" or hump "_∩_" "∈" "∋".​

Personally, I've found it's best to just have the dots. As for only having "T"s vs "+", the latter looks cleaner but gotta make sure to have those connection dots.


Here's a circuit snippet from a project I'm working on, the "BuzzBox" (2xBazzFuss) portion of it, reworked a couple of ways:

View attachment 45266

The two snippets above are identical, electrically, if the version to the right has D1, C5, Q1's Collector and R9 ALL connected at the "+", etc...


Here's how I'd handle a crossed path, if and where possible: View attachment 45267

"R20" and "C? 2µ2" need to cross the emitter of Q1, so I used a mix of grounding methods. However, since there's dots, I could just cross it:


View attachment 45268



Best advice I read was that a schematic is meant to convey information; If a schematic leaves a viewer scratching their head for any reason, is unclear in any way, then it should be adjusted to be concise and clear.



Have fun with the rest of your trace!
Click to expand...
Thanks, I use dots on paper but I forgot to add them in DIYLC so right now all lines that cross are connected
 
andare said:
Does it make sense?
Click to expand...

It's a DBA design.... it may never "make sense". :ROFLMAO:

As you mentioned, something missing on the source of Q1, whether it's direct to ground or to a resistor.

The volume control seems odd.... but that doesn't mean that's not how it is.

I feel like the tone control (R13 / C9 net) should come from the collector of Q3 rather than the emitter.

In either case, there's no coupling capacitor between Q3 and the tone control so you'll have a DC offset on the output.... which again, not typical, but also wouldn't surprise me given the circuit.

Also it looks like C7 is backwards.
 
Robert said:
It's a DBA design.... it may never "make sense". :ROFLMAO:

As you mentioned, something missing on the source of Q1, whether it's direct to ground or to a resistor.

The volume control seems odd.... but that doesn't mean that's not how it is.

I feel like the tone control (R13 / C9 net) should come from the collector of Q3 rather than the emitter.

In either case, there's no coupling capacitor between Q3 and the tone control so you'll have a DC offset on the output.... which again, not typical, but also wouldn't surprise me given the circuit.

Also it looks like C7 is backwards.
Click to expand...
And what makes you an expert exactly?

:)

Thanks for the pointers, man!
I'll take another look at the gut shots
 
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