I got this thing for $10 figuring either i could pick at it till i figure out whats wrong with it or get help from the various places made available to me through the internet. I come to you guys anyways, like the title says it's dead....and i believe it was an instore demo at guitar center for a while and it worked at one time. So, i took it home and took it apart, started looking at it and everything seems to be in working condition, and after messing with it for a while i realized that the battery gets hot when i have a cable in the input jack. Sound like something is getting crossed somewhere in the input jack or am I off my block?

I'd find the power rail and trace it around seeing if anything's shorting to ground anywhere....

I'd find the power rail and trace it around seeing if anything's shorting to ground anywhere....  Get a schem and check all the parts that connect to V+ and make sure they're not shorting...

extreme noob here, whats the easiest way to do that?

Find the Red wire and then find the black wire....

Where the red connects to the board, that trace is the source of power....make sure that it's not shorting to the black wire,.... also find any components that may look fried, unsolder one end, and then see if the circuit is still shorting

no fried components, can i get some help finding a schem?
cant find one and been looking for a while

Check the Schematics link at the top of the page,,,or Tonepad.com

it's definatly worth getting it going, I had one awile ago and it got stolen.  Keep working at it, I've been looking for a cheap one for ever.

You might want to put that aside and try building a few simple distortions.  That might not have been what you were planning on doing but it's lots a fun  :twisted:  A few simple builds would get you used to used to trouble shooting and terminology and what not.

Here's a link for the schematic.

No no, seriously.... here's the link.

http://www.tonepad.com/project.asp?id=13

http://www.tonepad.com/project.asp?id=7

One of them is for a phase 45 and the other is for the phase 90.  (The phase 90 is just a two stage 45)

I included them both because I can't remeber which was which and I though you might be interested.

look inside and find out if they installed a diode to prevent reverse polarity (one that connects  to the + and -)...could be that it failed as a short.  Unsolder one of the leads and check the pedal again...if it works, you know what it is...if it doesn't let me know.

Alf

the diodes look fine....and although they're close to the leads i cant actually see anywhere where - and + would be connected through one. How do i go about testing if stuff is grounding out? I'm borrowing a friend's voltage meter now....will that do the trick?

A visual inspection won't tell you.  Measure the continuity between the 2 leads in the diode. Do this test with the meter probes reversed also i.e., 1st time put the red probe on the anode and the black in the cathode and check...then reverse the probes and do this again...If there's a short it'll be very obvious....

my recommendation, unsolder 1 lead of that diode and test the pedal again.

Alf

well i unsoldered one side of both leads, actually breaking the larger of the 2 diodes on accident. whoops. anyways now the led comes on so i figure we're making progress in the right direction.....no phase effect though. now when i take a wire or something and connect the solderpoints before and after the diodes i can get short phases, only after contact and unconnecting it. we're close i can feel it....should i get on ordering some new diodes or what? do i even need them?

well i popped both diodes out and now i need help figuring out what their values are....one is broken so testing that one probably wont work. Or, can I assume that the values found in the schematics/layouts on tonepad are the same? only problem is they use 2 different sets. should i assume the ones on the phase 90 are what im looking for?

so you have a digital camera? if so take a pic of the board and I'll check on my side...I have 2 Phase 90 here.

Alf

I don't know what version you have, but...


The one in the corner of the board, which is usually copper coloured, is a 1N914.  The one near the trim pot, which is often a black one, is a 5.1V zener (most likely a 500mW type).

I think you have destroyed the zener which means you will have to adjust the trimpot to restore the proper JFET biasing.

Quote from: chokeyouwell i popped both diodes out and now i need help figuring out what their values are....one is broken so testing that one probably wont work. Or, can I assume that the values found in the schematics/layouts on tonepad are the same? only problem is they use 2 different sets. should i assume the ones on the phase 90 are what im looking for?

There are 2 diodes in the circuit...if you take the Zener out it'll affect the the bias on the Jfets.  That one has to be reinstalled - its a 5.1V Zener.

Do you have a reissue Phase 90 or the older version?  and yes, use the Tonepad schematic...D2 is the zener...I D1 is the one that had failed as a short (my best guess).

Alf

they're both like orange/red/black....ones about 3mm the other is 4mm.. thanks for the help

My guess is that the largest one is the Zener...which one did you break?

Alf

the bigger of the 2