DIY Fuzz Clone Question

[confused2015]

Hi guys,

Any help gratefully received. I am building a fuzz clone, and decided to be clever. I added a foot activated switch between the first and second transistors. Turned off, the signal runs from the collector of the first transistor to the output jack. On, it runs to the base of the second transistor.

However, I find that turning on the second transistor results in the voltages on all 3 legs of the first transistor dropping by about a third. What do I need to install between the two transistors to stop the second transistor affecting the voltages of the first transistor? A capacitor of some kind? And where?

Thanks in advance.

James

[Cozybuilder]

A schematic would be helpful

[antonis]

"A capacitor of some kind" should definately be installed between 1st transistor collector and 2nd transistor base despite of switching or not...

BUT...
We are waiting for the schematic..

[confused2015]

Ok, thanks guys. I will try to draw a schematic. Essentially it is two Dallas Rangemasters in one. When the switch is on, it becomes a fuzz face. Kinda. It seemed like a good idea at the time...

I am not familiar with correct schematic standards. I drew the foot switch as it appears. The audio signal comes in at the bottom middle. It goes out top middle. Left side represents switch off. Right side is on. The power comes into the middle middle. When switch is on, the power will run to the base leg and collector leg of the 2nd transistor. Sorry for the mess.

[duck_arse]

erm, I think you would be better to chuck this on the breadboard, first stage feeds second stage via a cap (but then you need bias for Q2 ....) all the time, get it working. then, connect the switch to select either Q1-C or Q2-C feeding the output.

and the name of this box when completed will be ........ ?

[antonis]

and the name of this box when completed will be ........ ?

TEDE Fuzz, perhaps..

(Tears in Eyes and Deafness in Ears - if there isn't another switchable Volume pot..)

[confused2015]

Hi guys,

sorry i wasn't clearer earlier. the thing is working fine, and there is a noticeable increase in gain and volume when engaging the 2nd transistor. but i measured the voltages of the first tranny when i turned the 2nd one on, and all 3 legs were down by about 1/3rd. that makes me thing that if i could stop the 2nd transistor impacting the voltages of the 1st, the box could be ever louder and even more oomph (technical term)

the schematic i drew isn't perfect i know, but should be enough for people to get the general idea of what i've done. so can anyone give me a hint? i have added a 0.05 cap between the c of Tranny 1 and b of tranny 2, which stops t1 affecting voltages of t2, but doesnt protect the voltages of t1.

should i add another cap somewhere? should it be a cap which has +/- ? where should it go? thanks

[Cozybuilder]

No schematic is showing up.

You could take a photo of it, put that on an on-line hosting site such as Photobucket or Imgur, direct copy from the hosting site, and place that between the brackets from the image icon on the toolbar, just below "B"

[duck_arse]

measure the voltage at the collector of Q1 when just it is "going" (technical term). stick in a cap, between the Q1 C and Q2 B. add a pair of resistors from V+ to ground, so that the voltage at their junction is the same as the V at Q1. connect that junction to the new cap//Q2 base. you now have isolated the stages and biased the second Q.

I'm not sure why you would want to do this ^, but it is something. I think. [I saw the schem. it wasn't pretty.]

[Cozybuilder]

I was able to get the schematic, and redrew it with DA's suggestion, and a couple of others:

To recap, you need a cap between Q1C and Q2B, anywhere from (22nf to 1uF will do), and you need a voltage divider to set the level for Q2B to the same V as Q1C.

In addition, assuming you want to switch the effect on and off using true bypass, you should stick in a bleedoff resistor at the input. and finally try a C1K pot for the fuzz rather than linear.

Hastily drawn: