freestompboxes.org

Here some detailed gut shot with component values.

That's cool silentfly!

Did you start reversing it? Or shall we go for it?

lolbou wrote:That's cool silentfly!

Did you start reversing it? Or shall we go for it?

I hopeless in tracing circuits. Please feel free to start without me.

The switch in the Q control board should be this.

The output is grey (signal) and white (gnd) wire.

I don't know the value of C11 but if we can't guess it looking at the schematics I will measure it.

I've just seen your link, sorry, there's one extra position?

In the 3 position version, some terminals are dummy. You can find more details here.

Cheers,

Any clue about the diode below the IC?

lolbou wrote:Cheers,

Any clue about the diode below the IC?

Runs from pin 8 to 4. Suggests reverse power supply protection. Therefore it's value is of limited importance for tracing the circuit.

Dirk_Hendrik wrote:

lolbou wrote:Cheers,

Any clue about the diode below the IC?

Runs from pin 8 to 4. Suggests reverse power supply protection. Therefore it's value is of limited importance for tracing the circuit.

I agree - something like a 1N400x should be ok.

Version 0.0...
Hope there ain't no big mistakes in it... ANd if someone has a better way to draw the Q-switch (to make if easier to understand) let me know!

BTW, I think the two pots were mislabelled (freq and level)... But what about values?

Apologies. You are right lolbou. The labels are wrong.

The values are correct. The double pot is A50K (freq) and the other one is A20K (level)

Some clips here!
Enjoy!
http://bass.forumeiros.com/reviews-f10/ ... -t2571.htm

The 47K resistor goes to ground,LED goes from positive via 10K,and switch is wrong.
In SHALLOW position should be C7 shunted by C5,R4 shunted by C6 and R7 in serries.
In DEEP position like there is no C5 and R7
In NORMAL position C7 is shorted and R4 shunted by C6.
hope this would help.

A LFO+LED/LDR could be added in to be used in place of the frequency pot to give a sort of auto wah...?

Silent Fly wrote:Apologies. You are right lolbou. The labels are wrong.

I had a hard time thinking on both sides of the PCB too... Where's left from right ?

This is what I have traced ,switch from top SHALLOW then DEEP and NORMAL

I'm a little confused in the configuration of the rotary switch. Anybody?

BTW, lietuvis's tracing is correct.

Pretty much identical to the Robin Tomtlund's trace of the "Fender JB Special preamp"!!! (probably 9 years old now)

http://hem.passagen.se/robin2/effects.htm

lietuvis wrote:The 47K resistor goes to ground,LED goes from positive via 10K,and switch is wrong.
In SHALLOW position should be C7 shunted by C5,R4 shunted by C6 and R7 in serries.
In DEEP position like there is no C5 and R7
In NORMAL position C7 is shorted and R4 shunted by C6.
hope this would help.

DimebuGG wrote:BTW, lietuvis's tracing is correct.

Back on it for next version...

DimebuGG wrote:I'm a little confused in the configuration of the rotary switch. Anybody?

Lieutevis made a better job on drawing it though!

i'm not quite sure why pot 1 is a dual. anyone have any idea?

Version 1.0:
Any better?

RnFR wrote:i'm not quite sure why pot 1 is a dual. anyone have any idea?

Some second order filter (two RC networks)for better selectivity in frequencies?

A similar filter configuration canbe found in the Ibanez ST-9, the Ibanez STL and the Pearl OD-5. All from the (early) 80´s.

analogguru