help with tubescreamer

[tubescreamer1010]

im new to building pedals and i recently started a tube screamer from tone pad. i used the old PCB and i think i may have also wired the pots wrong. it works in bypass mode
the IC measurments are
1. 2.0
2. 1.0
3. 3.0
4. 0
5. 7.5
6. 1.5
7. 1.5
8. 2.0

[petemoore]

  What does the battery measure without the circuit attached?

[markphaser]

whats the name of the IC and number ?

Is it a JFET IC chip? MOSFET IC chip? or Bipolar IC chip?

If pin 8 is the + power supply at 2 volts it should be 9volts so something is pulling it down

[g.e.o]

hey there!
the measurements dont seem right. check the form from the task what to do when it doesnt work in this forum and fill it with the measurements u find about the ic, q1, q2 and so...! from my experience the measurements are wrong so something is not workin properly. maybe its also the old layout that u used. the reports about it where sayin it had problems so why dont u start builting it again with the new layout. i made mine from tonepad and, if u except one mistake that tortured me for 4 days, it works fine.
hope i helped.
George

[g.e.o]

hey there!
the measurements dont seem right. check the form from the task what to do when it doesnt work in this forum and fill it with the measurements u find about the ic, q1, q2 and so...! from my experience the measurements are wrong so something is not workin properly. maybe its also the old layout that u used. the reports about it where sayin it had problems so why dont u start builting it again with the new layout. i made mine from tonepad and, if u except one mistake that tortured me for 4 days, it works fine.
hope i helped.
George

[tubescreamer1010]

im using a JRC4558 maybe im writing the pins down in the wrong order cause the battery measures 7.5 and so does one of the pins

[Seljer]

when you're looking at a dual opamp from above the pins are in the order as written in this picture: http://devices.sapp.org/component/opamp/tl072.gif (its for a tl072 but a 4558 has the same pinout)

pin 8 should be at the voltage of your battery
pin 4 should be at 0V

I believe the other pins usually end up being at half the voltage of your battery (Vr or whatever else its called in the schematic) but I can't be bothered to go measure my one to find the specifics.

[tubescreamer1010]

the IC measurments are
1. 2.0
2. 1.0
3. 3.0
4. 0
5. 2.0
6. 1.5
7. 1.5
8. 7.5

[tubescreamer1010]

i rechecked the measurements on the IC voltage cause i realized i had a bad battery and i got
1. 5.5
2. 5.0
3. 5.0
4. 0
5. 6.0
6. 6.0
7. 6.5
8. 9.5

[Barcode80]

voltages seem pretty normal, maybe you have a grounding issue somewhere. check for miniature solder bridges and make sure the circuit isn't grounding against the enclosure (if you have it in the enclosure)

[GibsonGM]

Well Tube, it looks like the IC has power, and the voltages seem OK based on 1/2 batt. supply biasing on the -, + and outputs (not sure if they're supposed to be there, but the idea makes sense).

As suggested, read thru "what to do when it doesn't work" at the top of the forum posts.
I use an audio probe when I get into this situation....I use it to track down where the problem lies, working my way back from the input.  Could even be the switch wired up incorrectly (maybe).  Or a capacitor in backwards, etc.  Info on audio probes is found under the "Wiki" link at the top of the page.
More symptoms would help us figure out what's going on    If it just DOES NOT WORK, the audio probe may be the way to go here...with ckt. removed from enclosure. 

[tubescreamer1010]

thank you for the advice i will get back to you on how that works

[g.e.o]

As GibsonGM already suggested, use the audio probe. thats how i made mine work. Btw when u have the ts on do u hear anythin? for example, do u hear ur guitar but without gain? give us some more info to help! 
George

[tubescreamer1010]

it works in bypass mod but when i turn it on i hear a lot of static and buzzing and no guitar

[g.e.o]

then i guess the only way my friend is to audio prob it. as already said here check it in the wiki link on the top of the page. its very easy to use and in ur case the only way to work it out.

[tubescreamer1010]

i used the audio prob and the signal didn't make it passed the first capacitor

[Barcode80]

well, i suggest checking that cap, or at least remelt the solder joint