What more do you want from Q214?
Don't the pads look exactly like the other pads that have no components?
Is your amp precisely the same revision as the ones with Q214 in place?
Don't the pads look exactly like the other pads that have no components?
Is your amp precisely the same revision as the ones with Q214 in place?
Q214 sometimes powers an extra 5v regulator (along with the 494) but in some amps, the circuit is different.
Did you install the inductor?
Did you install the inductor?
Ok, i see.
Yes the inductor and the ceramic cap next to it are back in there. Still the same.
So i was looking at the 339 and for what i understand is that on the 339, pin 10and 11are the inputs for the comparator and pin 13 is the output. I am getting +voltage on both when pin 10 should be -voltage. I also read short between pins 10 and 11 with the 339 installed, so i don’t know if it is comming from somewere else, or is internal. Any suggestions?
Yes the inductor and the ceramic cap next to it are back in there. Still the same.
So i was looking at the 339 and for what i understand is that on the 339, pin 10and 11are the inputs for the comparator and pin 13 is the output. I am getting +voltage on both when pin 10 should be -voltage. I also read short between pins 10 and 11 with the 339 installed, so i don’t know if it is comming from somewere else, or is internal. Any suggestions?
There is no negative input to the LM339. All inputs are positive. The + input is the non-inverting input for the comparator (1/4 of the 339). The - input is the inverting input for the comparator. Pins 10, 11 and 13 are all for one comparator. Read through the datasheet.
If 13 and 14 are in parallel, you also have to look at pins 8 and 9.
I don't think there is a problem with any of those inputs or outputs because the output is at the forward voltage of a diode. I think another comparator is holding the voltage down through a diode.
If 13 and 14 are in parallel, you also have to look at pins 8 and 9.
I don't think there is a problem with any of those inputs or outputs because the output is at the forward voltage of a diode. I think another comparator is holding the voltage down through a diode.
Ok i see. Now i just did some more poking around and decided to pull diode 202 to measure it off the board. This is the one that connects to pin 13 on the u202 339 (the first one i was messing with). The diode checked ok. So i decided to power it with the diode off and it had drive for a second. Then it went into protection. I left it on and measured on u203 339, the one that connects to q101 while it was on protection. Pin 10 was 5.2v and pin 11 was 0v. Pin 14 had 6.1v and everything on q101(the transistor by the 494) had@5v.
Now its clear why we checked and pulled q101, because it’s acting like the amp was on protect.
I noticed several resistors around the area with the white glue by the caps that are measuring the same voltage 5.2v across. Most were 1k and 2k. Should i pull them and measure them?
Now its clear why we checked and pulled q101, because it’s acting like the amp was on protect.
I noticed several resistors around the area with the white glue by the caps that are measuring the same voltage 5.2v across. Most were 1k and 2k. Should i pull them and measure them?
Lift Q101 again.
Do you have positive and negative rail voltage?
Do you have positive and negative regulated voltage on the power supply pins of the op-amps?
Does the amp draw excessive current?
Do you have positive and negative rail voltage?
Do you have positive and negative regulated voltage on the power supply pins of the op-amps?
Does the amp draw excessive current?
Ok so here is a quick overview, i’ll make a mote detailed post after i’m done gathering my and organizing my data.
I got 2 60n06 on the ps and with q101 i’m getting drive. So i installed the rectifiers and i’m getting rail voltage both positive and negative and its making it to the output fets (they are not installed). Half are getting positive rail on the center pin, the other half on the first pin iirc.
So went ahead and installed the regulators (everything is clamped to the heat sink) and i’m getting both regulated voltages @15v positive and negative. All the op amps have positive and negative 15v at least on 2 pins (i’ll get the pin numbers later) except the lm311 u201. That one has around 5v on a few pins.
Now the other 311 (don’t quote me on this, i have to go back out there and write this stuff down) the one closer to the speaker terminals, is getting pretty toasty and so is that q401 transistor close to it.
As for current draw, i didn’t measure it, but i’m running 2.5 amp fuses from the ps, and so far so good. One more thing i noticed is that the pads for q101 are now measuring:
B 1.668
C 0.845
E 5.069
I’ll go and gather some more detailed and organized information, and post it later. I just wanted to document a bit of the progress so far.
I got 2 60n06 on the ps and with q101 i’m getting drive. So i installed the rectifiers and i’m getting rail voltage both positive and negative and its making it to the output fets (they are not installed). Half are getting positive rail on the center pin, the other half on the first pin iirc.
So went ahead and installed the regulators (everything is clamped to the heat sink) and i’m getting both regulated voltages @15v positive and negative. All the op amps have positive and negative 15v at least on 2 pins (i’ll get the pin numbers later) except the lm311 u201. That one has around 5v on a few pins.
Now the other 311 (don’t quote me on this, i have to go back out there and write this stuff down) the one closer to the speaker terminals, is getting pretty toasty and so is that q401 transistor close to it.
As for current draw, i didn’t measure it, but i’m running 2.5 amp fuses from the ps, and so far so good. One more thing i noticed is that the pads for q101 are now measuring:
B 1.668
C 0.845
E 5.069
I’ll go and gather some more detailed and organized information, and post it later. I just wanted to document a bit of the progress so far.
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Ok, here i got some voltages from tl072 and the lm311.
Tl072c
Pin 1: 4.106
Pin 2: 0.160
Pin 3: 0.006
Pin 4: -14.990
Pin 5: 0.003
Pin 6: 0.002
Pin 7: 0.003
Pin 8: 15.03
Lm317
Pin 1: 0.015
Pin 2: 0.160
Pin 3: 0.922
Pin 4: 0.012
Pin 5: 4.360
Pin 6: 4.360
Pin 7: 0.150
Pin 8: 5.456
Tl072c
Pin 1: 4.106
Pin 2: 0.160
Pin 3: 0.006
Pin 4: -14.990
Pin 5: 0.003
Pin 6: 0.002
Pin 7: 0.003
Pin 8: 15.03
Lm317
Pin 1: 0.015
Pin 2: 0.160
Pin 3: 0.922
Pin 4: 0.012
Pin 5: 4.360
Pin 6: 4.360
Pin 7: 0.150
Pin 8: 5.456
Recheck 1, 2 and 3 of the TL072.
I don't know where it is in the circuit.
Is it driving the output stage?
What does it correspond to on the Sony diagram?
I don't know where it is in the circuit.
Is it driving the output stage?
What does it correspond to on the Sony diagram?
Ok, i’ll go ahead and recheck them. I decided put a signal into it, and i could see the square wave corresponding to my input frequency on pin 2 of the tl072 and from there it was on pin 1 of the transistors q401 and q403. Pin2 of the transistors had 65v and pin 3 nothing. The one closest to the 072 is getting hot and the 072 is getting extremely hot. The drive is not making it to the fet slots yet. I’ll check on the sony amp manual to see if anything resembles what i’m looking at.
I’m gonna see if i can craft me a heat sink for that 072 to see if i can keep the smoke inside it while i’m testing.
Thanks for your help.
I’m gonna see if i can craft me a heat sink for that 072 to see if i can keep the smoke inside it while i’m testing.
Thanks for your help.
Well, slipped a probe and zapped the -voltage reg. The smoke escaped out of the 072 and i’m getting -rail @-50v were i was getting regulated-19v. So i think the regulator is toasted also. Was about to put on the output fets too. Good thing i didn’t. I’m going to do a damage assessment and add up to the parts list. Should i go ahead and get all the op amps when i order parts?
I'm running a 600xd in my Jeep that I repaired a while ago. I don't have any photos of the board, but there are numerous places on the board that are not populated with components. On my amp, the "power on" LED is red only. Lit when power supply running, not lit when power supply not working/in protect. These 600xd (and 300xd) seem to fail in a similar way. Mine had: A bad TL072 (U401) which will cause neg. rail voltage on speaker terminal. Yes, this IC drives the output stage. I used a TLE2072 in place of the the TL072 (U401). Also, check for a shorted D118 zener diode (MMSZ5245) along with the Q2 neg. regulator which was also defective(2N6491). Also, both U1 & U3 TL074 quad op-amps were shorted along with those same IC's defective 10 ohm (0805) resistors R25,26 and R55,56. 5V is normal on the LM311 (U201). Normal rail voltage is +/- 60V. IRF3415 (have them in my amp) work well if the SSP45N20A output fets are defective.