I don't know that 2.6v is a valid logic low.  Several tests come to mind.  Monitor the output voltage at pin 3.  Zero volts.  Now briefly ground pins 1,2.  Does pin 3 go to a positive few volts?

Answer:
Yes 4.50vdc

QUOTE:Also at the flip flop, the collectors of Q1 Q2 should look the same.  We know what Q2 is doing, does the collector of Q1 have the same voltage levels?  or does it go closer to zero?

Answer:
Just to sure on this transistor it is ECB, if so the collector voltage does not change from 0 at all.  I'm having a hard time figuring out what transistor it is on the schematic  I see 2sc24500r  but not finding anything online about it.



Or turn the selector switch over to the end position where the two lines down to the 4011 are both not connected to anything.  Now, does that switching line from the flip flop still only go from 2.5 to 5?  Or does it now go closer to zero?


Answer:
Closer to Zero

Quote from: Enzo on August 05, 2015, 12:14:57 AM
I don't know that 2.6v is a valid logic low.  Several tests come to mind.  Monitor the output voltage at pin 3.  Zero volts.  Now briefly ground pins 1,2.  Does pin 3 go to a positive few volts?

Answer:
Yes 4.50vdc

QUOTE:Also at the flip flop, the collectors of Q1 Q2 should look the same.  We know what Q2 is doing, does the collector of Q1 have the same voltage levels?  or does it go closer to zero?

Answer:
Just to sure on this transistor it is ECB, if so the collector voltage does not change from 0 at all.  I'm having a hard time figuring out what transistor it is on the schematic  I see 2sc24500r  but not finding anything online about it.



Or turn the selector switch over to the end position where the two lines down to the 4011 are both not connected to anything.  Now, does that switching line from the flip flop still only go from 2.5 to 5?  Or does it now go closer to zero?


Answer:
Closer to Zero




Since IC passed the grounding test this must now point to Q1?  If so what could sub for it?


Thanks,
Jason

Quote from: Enzo on August 04, 2015, 06:23:03 PM
It is a logic gate wired as an inverter.  If a logic hi sits on pins 1 and 2, then pin 3 will sit at zero.  Since R6 is 1 meg, I doubt anything further along will affect pin 3.  The problem is either at the IC itself of in the circuit driving pins 1,2.

With the selector switch in the center two positions, the toggle line from the foot switch flip flop is connected to pins 1,2 of the 4011.  As I recall you had action on the FS output?  So does the same voltage changes appear at pins 1,2?

pin1 and 2 5.04vdc hit switch drops to 2.60vdc


So I should start looking at Q6 since pin 10 has the voltage that looks off to me?  Just a quick question : Would a logic probe be able to be used in verifying the IC good or bad?(Not that I have one)
Thanks,
Jason

Since there is no voltage on Pin3 of the 4011, my next guess is to follow it up to R6 D5 then Q9.  Will do that and post follow up.

Thanks,
Jason

pin1 5.29/2.62
pin2 5.30/2.62
pin 3 0/0
pin4 4.67/4.39
pin5 0/0
pin 6 5.27/2.61
pin 7 0/0
pin 8 5.30/4.99
pin 9 5.30/2.63
pin 10 .27/.29
pin 11 0/0
pin 12 5.31/5.01
pin 13 5.31/5.01
pin 14 9.15/9.02

Enzo quote:  The bottom line is this:  does that line coming from the flip flop up and over to the selector switch in the center of the schematic toggle up and down with the switch pushings?

Yes it does, comes in pin12 of ribbon cable goes through mode and level SW1a and b comes out pins 10 and 11(I checked both sides of ribbon and am getting voltage change with the switch on the main board pins 10 and 11.

Thanks,
nosaj

Ok. looking at bottom of board left to right

Q1  .03vdc 0vdc 4.41vdc hit switch 5.70vdc 0vdc .02 vdc
Q2  .61vdc 0vdc 4.42vdc hit switch .01vdc 5.42vdc 0vdc

4011 dc jack in North Direction measurements taken from bottom side left to right the slash between measurements will denote switch change. because I am really now confused as to pin numberings I will not number them at this time

Left side going down
9.15/9.02
5.31/5.01
5.31/5.01
0/0
.27/.29
5.30/2.63
5.30/4.99

Right side going down
5.29/2.62
5.30/2.62
0/0
4.67/4.39
0/0
5.27/2.61
0/0


Now Pin 11 on the ribbon cable  4.90vdc hit switch 5.11 vdc
Selector switch all the way to left.

I think the flipflop is working. But where you say Q1 and Q2 should have close to 9v getting about half that. I'm gonna zoom in on schematic and see

Thanks,
nosaj 

D12  8.93vdc
C44 8.90vdc
R61  8.90vdc other side 4.39vdc  this is the voltage divider?
r44 4.34
c45 4.34

So I guess now I need to trace 9v to q1 and q2 to see where it is dropping.  Would low voltage keep footswitch from disabling effect?

Ok no voltages at Q2  Will check r19 next. The arrow after r19 does that mean they ran out of room jump to other side of page to the power section? If so the 4.5v onr or the 5 volt one?

Voltages on 4011
pin1 5.14  hit switch 2.5
pin2 5.13                2.5
pin3  0                      0
pin4 4.5                 4.20
pin5 0                    0
pin6 5.09               2.5
pin7 0                   0
pin8 5.06              4.79
pin9 5.06               2.5
pin10 .28               .30
pin11 0                  0
pin12 5.07              4.79
pin13 5.07              4.79
pin14 8.71              8.52


What the heck are chip points?



Thanks for your help,
Jason

Dang..not sure what to say


Eat drink and be merry

I sure appreciate all your contributions  your posts are one of the top 3 I love to read .

Find your peace and share it with those you love. 

nosaj

I've got and SD-2 the effect won't turn off.  Effect works as well as all the dials and crunch lead selector just won't turn off when you hit footswitch.  I hooked my meter up to the leads on the circuitboard push button meter moves to right let go goes back left so the switch is good.  Not sure where to go from here.

Nosaj

Then in that case I'd check continuity in the power cable. Unplugged of course. Check all 3 wires  one probe on a blade of the plug and the other on the inside. See if moving the cable affects continuity.

nosaj

I would think the broken ground might be right there at the IEC connector on the inside, because of the way you flexed the cable causing it to complete a ground. Another thought is have you tried a different power cable?

nosaj

Is this it?
http://www.fender.com/guitar-amplifiers/contemporary/champion-100/product-2330400.html
Quick search turns up no schematic you may have to directly call them for one.

Thanks,
nosaj

QuoteJuan:

You mean like they just used the tube chassis and put a SS in there?  Would that explain the burnt choke?

nosaj

No, sorry if I wasn't clear.

They did it twice  :duh

First they copied the schematic of a Fender Twin or Dual Showman tube amp, (same thing) , used a narrower and taller chassis with one channel on top of the other, more typical of then current SS amps than then current tube amps (with a long narrow front panel with knobs in a long line) and to boot packaged it in an SS Kustom cabinet lookalike, complete with tuck and roll Naugahyde covering, even copying the "Frankenstein" version, so called for it huge "forehead" , yours shows the top panel much wider than the bottom one.
What were they thinking?

Guess which of these Kustom heads might be nicknamed "Frankenstein" :


Not to be outdone, then they made an amp head which by design, silkscreening, layout, etc could be considered an (unlabelled)  Peavey head, so much so that Peavey also sued them ... but still hiding a Tube Fender clone inside  :lmao:

FIRM candidates to commercial Darwin awards.

These pics show 4 6l6's so it's in 100watt class, could almost bet preamp is 12ax7 maybe at7 for PI.
http://instrumentcollection.blogspot.com/2011/08/vintage-plush-prb-1000-s-guitar.html

Thanks,
Jason

Quote"Instead he decided to state I was wrong and he was right.

As far as someone not blowing their own horn, it matters little to me what his pedigree is, just how he conducts himself. I can obviously see he wants to be helpful, but it should never be his aim to put someone else down, because of his own misconceptions.
Suffice to say I have had experience in all the areas you have stated he has, plus quite a few more in both pro audio and commercial electronics."Quote

Sounds like someone's ego got bruised.  maybe you need to go back and re read to see what your goal really is. That your right and he's wrong?  It's kind of time to let this go.


nosaj