im going to try to attempt to give this 2150 sx a rebirth, it doesnt look pretty... 
if possible can someone verify the location of these components?
i picked this amp up from a friend and its been from repairman, to repairman, to technician, to god knows who....its been through alot , and it still doesnt work and i feel sorry for it.
i removed most of the caps to replace them, but i want to be sure whoever took it apart previously put the components in the right place....
how do you check the 317/337/L7815 regulators?
at first i thought the fen/p 30 rectifiers on the back of the board were bad because the legs were melted off....but after soldering the legs back together im getting identical mirror image readings for both of them...
while in the board. .632 or with the leads reversed for each diode .380...on diode check.
good lord, where do i start with this amp?
btw...the supposed demise of this amp was a 2 ohm mono load for about 30 seconds (i know the minimum is 4 ohms mono, but shouldnt it atleast be able to hold out longer without blowing?)
if possible can someone verify the location of these components?
i picked this amp up from a friend and its been from repairman, to repairman, to technician, to god knows who....its been through alot , and it still doesnt work and i feel sorry for it.
i removed most of the caps to replace them, but i want to be sure whoever took it apart previously put the components in the right place....
how do you check the 317/337/L7815 regulators?
at first i thought the fen/p 30 rectifiers on the back of the board were bad because the legs were melted off....but after soldering the legs back together im getting identical mirror image readings for both of them...
while in the board. .632 or with the leads reversed for each diode .380...on diode check.
good lord, where do i start with this amp?
btw...the supposed demise of this amp was a 2 ohm mono load for about 30 seconds (i know the minimum is 4 ohms mono, but shouldnt it atleast be able to hold out longer without blowing?)
An externally hosted image should be here but it was not working when we last tested it.
The components on top of the board are correct. I'm not sure about the two on the bottom but you can follow the center leads to the rail caps to see which goes to the positive rail caps and which goes to the negative rail caps.
Why do you suspect the regs?
What happens if you power it up? You should install at least one positive and one negative rail cap before powering it up.
Why do you suspect the regs?
What happens if you power it up? You should install at least one positive and one negative rail cap before powering it up.
ive checked all the fets and transistors and replaced defective ones and it doesnt power up. ive checked and replaced the a56/06 and relative diodes also.
i guess im just being suspicious of the regs because , its the grey area i dont know how to check.
but let me put everything back together again and see what happens as this amp has been sitting for a while...and i may have forgotten something.
how do the readings for diodes look on the back? or do i have to pull them to get better readings? they look beat to heck, but seem to measure while 'in board'...just weird that they measure at all if i reverse the leads.
ill get back to this tomoorrow, im beat to heck right now, installed 6 speakers...made a ported box for 2-10's , hooked up 3 amps from battery...made an amprack....and wired an oem hu via loc to a pre-amp today...
and soldered everything....
i guess im just being suspicious of the regs because , its the grey area i dont know how to check.
but let me put everything back together again and see what happens as this amp has been sitting for a while...and i may have forgotten something.
how do the readings for diodes look on the back? or do i have to pull them to get better readings? they look beat to heck, but seem to measure while 'in board'...just weird that they measure at all if i reverse the leads.
ill get back to this tomoorrow, im beat to heck right now, installed 6 speakers...made a ported box for 2-10's , hooked up 3 amps from battery...made an amprack....and wired an oem hu via loc to a pre-amp today...
and soldered everything....
put the caps back in today and powered it up...
when i power it up the ammeter needle stays pegged to 100 amps...100 amps is the maximum value on the ammeter.
i took the secondary windings out of the board and powered up again...but left those two wires in that go between the primary and secondary
the ammeter goes to 10 amps, then there is a 5 second delay then the needle goes to 35 amps very slowly, and stays there.
still want me to mesure the TL494? (this one doesnt use the 594)
when i power it up the ammeter needle stays pegged to 100 amps...100 amps is the maximum value on the ammeter.
i took the secondary windings out of the board and powered up again...but left those two wires in that go between the primary and secondary
the ammeter goes to 10 amps, then there is a 5 second delay then the needle goes to 35 amps very slowly, and stays there.
still want me to mesure the TL494? (this one doesnt use the 594)
An externally hosted image should be here but it was not working when we last tested it.
with the secondaries legs out of the board.
the initial voltage the amp draws from my power supply/battery charger is 15.69 vdc (10 amps)
then it rest at 14.65 vdc (10 amps) for a few seconds, then it drops down to 11.43vdc...as the ammeter starts to rise to 35 amps, and stays there.
with the secondary legs out...and measured at 11.43 vdc, here are the mesurements for the TL494
1 = -0.003
2 = 0.032
3 = 0.032
4 = 0.048
5 = 1.568
6 = 3.516
7 = 0.002
8 = 11.74
9 = 0.002
10= 0.033
11= 5.022
12= 5.022
13= 11.96
14= 11.78
15= 4.91-98
16= 4.91-98
or should i measure while the secondaries are in? its drawing alot of current with them in and im afraid something is going to fry if i leave it powered up too long.
the initial voltage the amp draws from my power supply/battery charger is 15.69 vdc (10 amps)
then it rest at 14.65 vdc (10 amps) for a few seconds, then it drops down to 11.43vdc...as the ammeter starts to rise to 35 amps, and stays there.
with the secondary legs out...and measured at 11.43 vdc, here are the mesurements for the TL494
1 = -0.003
2 = 0.032
3 = 0.032
4 = 0.048
5 = 1.568
6 = 3.516
7 = 0.002
8 = 11.74
9 = 0.002
10= 0.033
11= 5.022
12= 5.022
13= 11.96
14= 11.78
15= 4.91-98
16= 4.91-98
or should i measure while the secondaries are in? its drawing alot of current with them in and im afraid something is going to fry if i leave it powered up too long.
Did you use the old rail caps? Is it possible that you installed one backwards or that one is shorted?
You need to use a current limiter like a 1-2 ohm high power resistor or an automotive head lamp in the B+ line to prevent excessive current draw. It's unbelievable that the amp's power supply drew 100 amps from the 12v supply without failing. It won't be able to do that too many times without failing.
If the caps aren't the problem, the current limiter will make troubleshooting easier.
The voltage on the 494 looks OK. Look up the datasheet. You have the pin numbering backwards on the top row.
You need to use a current limiter like a 1-2 ohm high power resistor or an automotive head lamp in the B+ line to prevent excessive current draw. It's unbelievable that the amp's power supply drew 100 amps from the 12v supply without failing. It won't be able to do that too many times without failing.
If the caps aren't the problem, the current limiter will make troubleshooting easier.
The voltage on the 494 looks OK. Look up the datasheet. You have the pin numbering backwards on the top row.
Dear Clipped,
I think your TL494 voltages are wrong. I suggest you to pull the FEP16 rectifier diodes to repair your PS instead of the complete amplifier. Check your TL494 at first or regulation lines for it. Because pin8&11 or pin9&10 should have same voltage readings. I suggest you to check, if pin9&10 is going to GND (or pin7). If so, then you can check mosfets. But, I wonder if you are reading 11V for either pin 8 or 11 one of your switching mosfet is burned. Also it can damage TL494 . I think it is easy to check the current with an ammeter by pulling up the TL494. If the circuit still needs more current higher from 1A, you should check the mosfets at first. Please, turn back with your results.
Regards
I think your TL494 voltages are wrong. I suggest you to pull the FEP16 rectifier diodes to repair your PS instead of the complete amplifier. Check your TL494 at first or regulation lines for it. Because pin8&11 or pin9&10 should have same voltage readings. I suggest you to check, if pin9&10 is going to GND (or pin7). If so, then you can check mosfets. But, I wonder if you are reading 11V for either pin 8 or 11 one of your switching mosfet is burned. Also it can damage TL494 . I think it is easy to check the current with an ammeter by pulling up the TL494. If the circuit still needs more current higher from 1A, you should check the mosfets at first. Please, turn back with your results.
Regards
yes i listed the pins backwards...right when i did, my ISP cut me off and have been trying to correct it for 24 hours, the whole time thinking 'what an idiot i was'...
btw pin#1 is not negative...i think its time to change the battery in this meter...
man really sorry for posting wrong stuff.
i used new rail caps i just purchased yesterday 50v 1000uf
all put in correctly, and i checked each and everyone before putting them in to make sure there would be no question about them.
but the sideways caps (old ones) act funny, sometimes they say 'disc' and sometimes they meter.
there is one problem area on this board where it has cracked across a few traces...on the other side is an A56
-------------------------------------------------------------
so should i get some current limiting resistors , put the secondaries back in and remeasure the TL494 ?
-------------------------------------------------------------
btw pin#1 is not negative...i think its time to change the battery in this meter...
man really sorry for posting wrong stuff.
i used new rail caps i just purchased yesterday 50v 1000uf
all put in correctly, and i checked each and everyone before putting them in to make sure there would be no question about them.
but the sideways caps (old ones) act funny, sometimes they say 'disc' and sometimes they meter.
there is one problem area on this board where it has cracked across a few traces...on the other side is an A56
-------------------------------------------------------------
so should i get some current limiting resistors , put the secondaries back in and remeasure the TL494 ?
-------------------------------------------------------------
An externally hosted image should be here but it was not working when we last tested it.
I don't know what meter you have but the 'disc' likely means that you need to discharge the capacitor or the meter is in the process of discharging the cap.
Electrolytic caps have a fault/property called dielectric absorption. It's where the cap acts a bit like a battery. Even if you short the leads together, the cap will recharge to some degree. That could be causing your problem when trying to check them.
The current limiting resistor generally makes it easier to find faults when excessive current draw is a problem. For example, you can power the amp up via the resistor and measure the voltage across the emitter resistors. If you find one channel (or even a single resistor) with abnormally high voltage across it, that will generally narrow down the area in which to look. It also allows you to meaure the voltage across other resistors and transistors with little or no chance of damaging the amp. You have to have the amp mounted in the sink so the transistors won't get hot. Generally, the only time you'll have a problem is for amps that shut down due to low voltage and with the older Orions that don't have the PWM IC in the power supply.
The voltages you posted were good enough. You don't need to take any more on the 594 for now.
Can you pull one end of each of the emitter resistors (secondary soldered back in place)? If the excessive current draw was eliminated, that would let you know that the problem was in the audio section. You could do one channel at a time.
Electrolytic caps have a fault/property called dielectric absorption. It's where the cap acts a bit like a battery. Even if you short the leads together, the cap will recharge to some degree. That could be causing your problem when trying to check them.
The current limiting resistor generally makes it easier to find faults when excessive current draw is a problem. For example, you can power the amp up via the resistor and measure the voltage across the emitter resistors. If you find one channel (or even a single resistor) with abnormally high voltage across it, that will generally narrow down the area in which to look. It also allows you to meaure the voltage across other resistors and transistors with little or no chance of damaging the amp. You have to have the amp mounted in the sink so the transistors won't get hot. Generally, the only time you'll have a problem is for amps that shut down due to low voltage and with the older Orions that don't have the PWM IC in the power supply.
The voltages you posted were good enough. You don't need to take any more on the 594 for now.
Can you pull one end of each of the emitter resistors (secondary soldered back in place)? If the excessive current draw was eliminated, that would let you know that the problem was in the audio section. You could do one channel at a time.
well i took more TL494 readings with the secondaries back in place and used five 10ohm resistors...inline with the B+
didnt read your post in time
i also changed the fen/p16 diodes although they were still good.
the amp is only seeing 8.04vdc after the resistor, the led wont light, and the ammeter doesnt budge.
1=0.001
2=0.029
3=0.029
4=0.032
5=1.562
6=3.5
7=0.01
8=6.5
9=0.423
10=0.38
11=6.515
12=6.529
13=5.019
14=5.09
15=0.029
16=0.001
didnt read your post in time
i also changed the fen/p16 diodes although they were still good.
the amp is only seeing 8.04vdc after the resistor, the led wont light, and the ammeter doesnt budge.
1=0.001
2=0.029
3=0.029
4=0.032
5=1.562
6=3.5
7=0.01
8=6.5
9=0.423
10=0.38
11=6.515
12=6.529
13=5.019
14=5.09
15=0.029
16=0.001
i took out the emitters on the side with the mono/eq button and the current draw dropped down to 20 amp (constant)
then i took out the emitters onthe other side and it still stays at 20 amps.
it initially jumps to 40 when power is first applied. then drops to 20.
---------------------------------------
i have to look for more resistors to add to my ghetto power resistor...one moment
then i took out the emitters onthe other side and it still stays at 20 amps.
it initially jumps to 40 when power is first applied. then drops to 20.
---------------------------------------
i have to look for more resistors to add to my ghetto power resistor...one moment
20 amps is probably safe for a few seconds at a time as long as the transistors are tightly clamped to the heatsink.
Can you find anything heating up?
Have you checked to see if the tabs of any of the heatsink mounted components were shorted to the sink?
Do you see anything different on yours compared to this one:
http://www.bmpt1.com/images/IMG_1383b.jpg
If it fits on the screen, your browser is likely resizing it.
Can you find anything heating up?
Have you checked to see if the tabs of any of the heatsink mounted components were shorted to the sink?
Do you see anything different on yours compared to this one:
http://www.bmpt1.com/images/IMG_1383b.jpg
If it fits on the screen, your browser is likely resizing it.
these 2 pre drivers are extremely hot....
i know these are impossible to get here...so maybe the game is over for this amp , unless there is an altenative to these parts.
i cant get the originals over here. ....but i think i read on this board that it may be possible to use the 2N6481/91's in their place....cant remember that well.
in that pic its hard to see the color of the resistor bands.
-------------------------------------------------------------------------
what value are the gate resistors for the power supply fets, cause i got blue ones in this amp.
-------------------------------------------------------------------------
for my ghetto power resistor, think 0.8 ohms would be ok?
i know these are impossible to get here...so maybe the game is over for this amp , unless there is an altenative to these parts.
i cant get the originals over here.
....but i think i read on this board that it may be possible to use the 2N6481/91's in their place....cant remember that well.in that pic its hard to see the color of the resistor bands.
-------------------------------------------------------------------------
what value are the gate resistors for the power supply fets, cause i got blue ones in this amp.
-------------------------------------------------------------------------
for my ghetto power resistor, think 0.8 ohms would be ok?
An externally hosted image should be here but it was not working when we last tested it.
If those drivers are getting hot, they are likely defective or the outputs connected to them are defective. Pull them and check them for leakage (I'm assuming that you've already checked to see if they were shorted).
There are lots of options for those drivers. I think they are being produced by Central Semiconductor.
http://pdf1.alldatasheet.com/datasheet-pdf/view/100395/CENTRAL/CENU07.html
The two transistors are predrivers and drivers. You can use the original MPSU07/57 for the drivers (the ones that drive the outputs) and use something like a MPSW42 or MPSW92 for the predriver (the ones that drive the drivers).
You could use something like the 2n6488/91 but you'd have to hard wire them or twist the leads to make them fit.
This is a partial schematic of the audio section:
http://www.bmpt1.com/images/orion01.swf
The two TO-92 transistors in place of the u07/57 were used for testing. The amp was abandoned so I never finished it.
The missing a06 is for over-current protection if I'm not mistaken.
The two missing transistors in your amp are the muting transistors. They should be 2N5639s.
The gate resistors are 10 ohms.
There are lots of options for those drivers. I think they are being produced by Central Semiconductor.
http://pdf1.alldatasheet.com/datasheet-pdf/view/100395/CENTRAL/CENU07.html
The two transistors are predrivers and drivers. You can use the original MPSU07/57 for the drivers (the ones that drive the outputs) and use something like a MPSW42 or MPSW92 for the predriver (the ones that drive the drivers).
You could use something like the 2n6488/91 but you'd have to hard wire them or twist the leads to make them fit.
This is a partial schematic of the audio section:
http://www.bmpt1.com/images/orion01.swf
The two TO-92 transistors in place of the u07/57 were used for testing. The amp was abandoned so I never finished it.
The missing a06 is for over-current protection if I'm not mistaken.
The two missing transistors in your amp are the muting transistors. They should be 2N5639s.
The gate resistors are 10 ohms.
ok pulled out those hot ones, they were bad...pulled out the rest of them and found one more bad 07.
put the emitter resistors on the outputs back in place and powered it up...current draw dropped down to normal, or so i think, my ammeter starts at 10 and thats where it is sitting at.
the pre-drivers in this amp are currently the A56/A06...are these the originals?
i think i may choose to run the 2ne6488/91 for the drivers with the legs bent around to accomodate EBC opposed to BCE.
would you know what differences i can expect if i use the 2ne's as drivers? will there be severe performance differences, excess heat build up, gain differences, pros / cons....to be associated?
the mpsu is listed at 2 watts, but the 2ne's are listed around 75 watts....or will they run cooler and possibly better than the mpsu's....? or will they drive the outputs too hard?
will they last for the life of the amp? those replacement parts are really hard to find here, i can usually find one side of the complimentary pair, but then i get left high and dry for the other side.
put the emitter resistors on the outputs back in place and powered it up...current draw dropped down to normal, or so i think, my ammeter starts at 10 and thats where it is sitting at.
the pre-drivers in this amp are currently the A56/A06...are these the originals?
i think i may choose to run the 2ne6488/91 for the drivers with the legs bent around to accomodate EBC opposed to BCE.
would you know what differences i can expect if i use the 2ne's as drivers? will there be severe performance differences, excess heat build up, gain differences, pros / cons....to be associated?
the mpsu is listed at 2 watts, but the 2ne's are listed around 75 watts....or will they run cooler and possibly better than the mpsu's....? or will they drive the outputs too hard?
will they last for the life of the amp? those replacement parts are really hard to find here, i can usually find one side of the complimentary pair, but then i get left high and dry for the other side.
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