hey redblaze, i got your message in the other post, but im at work right now...let me know if you need any measurements.
just wondering, when you screw the board back in, does the board bend do to the diodes mounted on the back?
did you inspect the area with the cracks i posted?
ym ps fets were running unevenly hot also, but they went back to normal after i changed that 18 18 18 transistor.
just wondering, when you screw the board back in, does the board bend do to the diodes mounted on the back?
did you inspect the area with the cracks i posted?
ym ps fets were running unevenly hot also, but they went back to normal after i changed that 18 18 18 transistor.
have you checked that tantulum on the mct2? ...does your meter have a capacitor setting?
check these two pages:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=97689&perpage=10&pagenumber=10
http://www.diyaudio.com/forums/showthread.php?s=&threadid=97689&perpage=10&pagenumber=11
http://www.diyaudio.com/forums/showthread.php?s=&threadid=97689&perpage=10&pagenumber=12
check these two pages:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=97689&perpage=10&pagenumber=10
http://www.diyaudio.com/forums/showthread.php?s=&threadid=97689&perpage=10&pagenumber=11
http://www.diyaudio.com/forums/showthread.php?s=&threadid=97689&perpage=10&pagenumber=12
I did check to see if there were any cracked traces or spots that copmress and realease when screwed down and there are none, I checked each fet on AC V and each fet checked out the same on the gate resistor with the probe on the fet itself as directed so no changes there , I measured the a06 and a56 while powerd up and on each a06 on each inside leg near the middle of the amp I get a reading of 3.75VDC does that seem kinda high ? on another 2150SX that can be turned on outside the heatsink I get lower readings on the fets and on the a06's and the 2n6488 doesnt get as hot. what drives the a56 and a06 in the powersupply ? I will change those out , I took them out and they checked fine before reinstalling them , but both sets on each side do give the same readings so that is why I am wondering what drives them becasue maybe I can trace the problem back.
on the transisotrs that read 18,18,18 I get the same readings as you Clipped after you put good ones in.
thanks
redblaze
on the transisotrs that read 18,18,18 I get the same readings as you Clipped after you put good ones in.
thanks
redblaze
http://bmpt1.com/images/orionpartial03.swf
This may have errors. There are definitely omissions.
Right-click to zoom in.
This may have errors. There are definitely omissions.
Right-click to zoom in.
Ok , from the schematic I can trace it back but all parts are good, I did change the a06 and a56 for both banks .
it now turns on and can stay out of the heatsink Right side PS fets still get warmer than Left side , in fact lefts side barely gets warm at all , but there is no more hiss from the torroid either.
all of the values on the schematic I get on the amp are very very close , I taced everything back with the MM with the amp powered up and off , also checking to make sure the resisitors were within tollerance. now after the change of the a06 and a56 like i said torroid hiss has vanished and the fets stay cool enough out of the heatsink.
but my confusion still lies in the fact that the right side still gets warmer than the left side of fets ( right side you can deffinatley tell they are warm some get a little hot but cool off on their own left side just barely warm) so there may be a problem still but its got to be samll unless I am just being overly cautious with the fets.
Funny thing is that the old a56 and a06 still check fine out of the board, and even gave good readings in the board also the voltages went up with the new a06's on the inside legs toward the center of the amp on each a06 I got a reading of 3.79 , now on the new ones its 3.90.
redblaze
it now turns on and can stay out of the heatsink Right side PS fets still get warmer than Left side , in fact lefts side barely gets warm at all , but there is no more hiss from the torroid either.
all of the values on the schematic I get on the amp are very very close , I taced everything back with the MM with the amp powered up and off , also checking to make sure the resisitors were within tollerance. now after the change of the a06 and a56 like i said torroid hiss has vanished and the fets stay cool enough out of the heatsink.
but my confusion still lies in the fact that the right side still gets warmer than the left side of fets ( right side you can deffinatley tell they are warm some get a little hot but cool off on their own left side just barely warm) so there may be a problem still but its got to be samll unless I am just being overly cautious with the fets.
Funny thing is that the old a56 and a06 still check fine out of the board, and even gave good readings in the board also the voltages went up with the new a06's on the inside legs toward the center of the amp on each a06 I got a reading of 3.79 , now on the new ones its 3.90.
redblaze
Ok , I hooked up the 2150 in the car and all is fine with it, thank you Perry and Clipped.
so now I started work on the other 2 , the first 1 we just got fixed works great and at the gate resisitors in the PS I get a reading of 2.19 VDC now on the other 2 I replaced the PS transistors and only on 1 replaced the a56 and a06's , the 1 that I didnt replace them in has torroid Hiss so I am going to replace them.
anyway I think both of these other 2 2150SX's have the same problem , Like I started to say before on the gate resisitors in the PS on the working 2150 I get 2.19 VDC on these other 2 I get 1.56 on the gate resisitors and on the a06's on the good 2150 I get 4.05VDC on the both inside legs near the middle of the amp, I did change out the 7815 and the 2n6488 on the good 1 aswell.
on the other 2 orions I get 2.33VDC on those inside legs , now both of the other orions can be left out of the heatsinks and turned on and the PS transistors dont overheat , and they both play music , BUT on my powersupply I use, the 2150 we just fixed can play bridged and stereo at loud volumes without overloading and shutting down my powersupply, these other 2 play but I am not able to use the same volume or gain settings as the newly fixed 1 these 2 shut it down at lower gain settings and volume.
since they dont overheat out of the heatsinks and they both play music , I have checked all the diodes and gate resistors and voltages in the audio sections and all transistors are new , only thing I can figure to change is the a06's and 56's and the 7815 and 2n6488.
thanks
redblaze
so now I started work on the other 2 , the first 1 we just got fixed works great and at the gate resisitors in the PS I get a reading of 2.19 VDC now on the other 2 I replaced the PS transistors and only on 1 replaced the a56 and a06's , the 1 that I didnt replace them in has torroid Hiss so I am going to replace them.
anyway I think both of these other 2 2150SX's have the same problem , Like I started to say before on the gate resisitors in the PS on the working 2150 I get 2.19 VDC on these other 2 I get 1.56 on the gate resisitors and on the a06's on the good 2150 I get 4.05VDC on the both inside legs near the middle of the amp, I did change out the 7815 and the 2n6488 on the good 1 aswell.
on the other 2 orions I get 2.33VDC on those inside legs , now both of the other orions can be left out of the heatsinks and turned on and the PS transistors dont overheat , and they both play music , BUT on my powersupply I use, the 2150 we just fixed can play bridged and stereo at loud volumes without overloading and shutting down my powersupply, these other 2 play but I am not able to use the same volume or gain settings as the newly fixed 1 these 2 shut it down at lower gain settings and volume.
since they dont overheat out of the heatsinks and they both play music , I have checked all the diodes and gate resistors and voltages in the audio sections and all transistors are new , only thing I can figure to change is the a06's and 56's and the 7815 and 2n6488.
thanks
redblaze
check the pre-drive and drive transistors (MPSU) 8 total
touch them first to see if they get hot, they should be warm at normal operating temperature.
check for dc on the outputs.
also check the tantulum and resistor connected to the 5534 opamps (not the 5532) they will connect to either the b- or b+ and tie into ground...
check the caps too if your meter has a cap checker.
i suppose those other 2 2150sx's arent for sale anymore huh?
touch them first to see if they get hot, they should be warm at normal operating temperature.
check for dc on the outputs.
also check the tantulum and resistor connected to the 5534 opamps (not the 5532) they will connect to either the b- or b+ and tie into ground...
check the caps too if your meter has a cap checker.
i suppose those other 2 2150sx's arent for sale anymore huh?
Since you don't have a scope, you should change both driver transistors for each bank of PS FETs. Don't forget to check the 10 ohm resistor to ground on the collector of the A56 driver.
I've never seen the driver 2n6488 fail and I've never seen the 7815 fail in the power supply drive section. If they failed, it would generally cause a lack of drive voltage. You can check the 7815 by measuring the DC voltage on the third leg. It should be 15v if the voltage on the first leg is at ~17+v. You can check the 6488's operation by monitoring the voltage on the collector of the A06 driver. If the voltage on the A06 collector goes up when there is more current demand or when the B+ input voltage drops, the 6488 is working properly.
The difference in drive voltage (compared to the other 2150) doesn't necessarily mean that there's a problem. Differences in the threshold voltage of the transistors in the power supply as well as the B+ input voltage can make a relatively large difference in the drive voltage needed to maintain the target rail voltage.
You said that these amps were shutting the supply down more easily (compared to the other amp) at a given volume/gain setting. If the EQ is engaged (on the amp), that could make a big difference.
I've never seen the driver 2n6488 fail and I've never seen the 7815 fail in the power supply drive section. If they failed, it would generally cause a lack of drive voltage. You can check the 7815 by measuring the DC voltage on the third leg. It should be 15v if the voltage on the first leg is at ~17+v. You can check the 6488's operation by monitoring the voltage on the collector of the A06 driver. If the voltage on the A06 collector goes up when there is more current demand or when the B+ input voltage drops, the 6488 is working properly.
The difference in drive voltage (compared to the other 2150) doesn't necessarily mean that there's a problem. Differences in the threshold voltage of the transistors in the power supply as well as the B+ input voltage can make a relatively large difference in the drive voltage needed to maintain the target rail voltage.
You said that these amps were shutting the supply down more easily (compared to the other amp) at a given volume/gain setting. If the EQ is engaged (on the amp), that could make a big difference.
I did check the drive transistors or gate transistors they were all ok , actually I did have to change 1 but all the others were ok , I will check the Tantulum and resisitors to the 5534.
Well i would sell the 2150's but the shop owner I told you about with some for sale said if I get these 2 2150's fxed he will trade me those 2 for a 2250 thats in excellent condition and I had him open the 2250 up so I could look at it and test it.
for some odd reason which I obviously dont know , I have 2 different versions of the 2150sx the 1 we just fixed has a resistor on the left side (yellow) all the way at the back of the PS that connects to the inner most leg of the a56 the other 2 dont have this and its not missing,there is just no trace and no solder points for it.
there are 2 small spots that look like something solders there but this resistor connects over top of those to 2 differsnt solder points and its all factory the trace is in the board, the other 2 have the 2 small solder points but not the other 2 that this resistor connects to nor do they have the trace, and a few other small differences like the other 2 have bigger black diodes in places the first 2150 has small clear red ones only in the PS though the audio sections are the same , and in the PS on the left side (yellow ) from that 1 resistor at the beginning if you go 3 resistors up there is a diode by the fet but on the other 2 if you go up 2 resistors (because they dont have the first resistor) then you have another resistor where the diode is on the first amp.
do you guys know why this is like this? is 1 version better than the other ?
If the trade falls through I will sell those other 2 2150's
Perry
I will check the voltages on the 2n6488 and the 7815 just to be sure thank you for telling me how to check them that would have been my next question on my powersupply when I test all 3 of the amps I have the EQ button engaged , maybe the differences in the 2 amps compared to this 1 2150 may be the reason these other 2 shut the powersupply down faster ? everything in the audio sections of all 3 amps is the same.
thanks
redblaze
Well i would sell the 2150's but the shop owner I told you about with some for sale said if I get these 2 2150's fxed he will trade me those 2 for a 2250 thats in excellent condition and I had him open the 2250 up so I could look at it and test it.
for some odd reason which I obviously dont know , I have 2 different versions of the 2150sx the 1 we just fixed has a resistor on the left side (yellow) all the way at the back of the PS that connects to the inner most leg of the a56 the other 2 dont have this and its not missing,there is just no trace and no solder points for it.
there are 2 small spots that look like something solders there but this resistor connects over top of those to 2 differsnt solder points and its all factory the trace is in the board, the other 2 have the 2 small solder points but not the other 2 that this resistor connects to nor do they have the trace, and a few other small differences like the other 2 have bigger black diodes in places the first 2150 has small clear red ones only in the PS though the audio sections are the same , and in the PS on the left side (yellow ) from that 1 resistor at the beginning if you go 3 resistors up there is a diode by the fet but on the other 2 if you go up 2 resistors (because they dont have the first resistor) then you have another resistor where the diode is on the first amp.
do you guys know why this is like this? is 1 version better than the other ?
If the trade falls through I will sell those other 2 2150's
Perry
I will check the voltages on the 2n6488 and the 7815 just to be sure thank you for telling me how to check them that would have been my next question
on my powersupply when I test all 3 of the amps I have the EQ button engaged , maybe the differences in the 2 amps compared to this 1 2150 may be the reason these other 2 shut the powersupply down faster ? everything in the audio sections of all 3 amps is the same. thanks
redblaze
i know there are different versions of the 250hcca, one has the extra cap the other one doesnt...for the hcca the one without the cap was louder when i compared them.
well if the trade doesnt go through, let me know...but i know youll be able to fix them and trade more than likely... then youll have a 2250 to fix
well if the trade doesnt go through, let me know...but i know youll be able to fix them and trade more than likely...
then youll have a 2250 to fix - Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.