Until you restore the regulated voltage, you're not going to have clean audio and are likely to have DC offset.
Looking at the photo I attached in post #57, where do you lose the regulated voltage?
I didn't realize that the current draw was back to ~1 amp. I thought it was at 12 amps still. You can remove the jumpers if the current draw remains less than 2 amps.
Unless there is a pulled via, the muting transistors do not need to be in the circuit.
Looking at the photo I attached in post #57, where do you lose the regulated voltage?
I didn't realize that the current draw was back to ~1 amp. I thought it was at 12 amps still. You can remove the jumpers if the current draw remains less than 2 amps.
Unless there is a pulled via, the muting transistors do not need to be in the circuit.
just to double check the current draw, could you tell me how to figure it out correctly?
measuring across the power resistor, i can figure it out, but with it out..im not sure how to do it.
i just rely on the ammeter on the charger without the resistor in place, but it is 10 amps minimum on the needle, and im pretty sure it is not accurate.
i have a clamp meter but i dont trust it.
measuring across the power resistor, i can figure it out, but with it out..im not sure how to do it.
i just rely on the ammeter on the charger without the resistor in place, but it is 10 amps minimum on the needle, and im pretty sure it is not accurate.
i have a clamp meter but i dont trust it.
If you have the series resistor in the B+ line, the current draw is:
voltage across the resistor divided by the resistor value
If you have 1 volt across a 0.8 ohm resistor, the current draw is 1.25 amps.
voltage across the resistor divided by the resistor value
If you have 1 volt across a 0.8 ohm resistor, the current draw is 1.25 amps.
i may have found something...
the 3 ohm resistor to the immediate right of the 5534 in the orange channel, is bad, .....there is also a orange teardropped shape mylar cap that doesnt measure...they are both connected together.
this mylar cap is tied into the ground plane, with voltage coming in through the other leg via the 3 ohm resistor.
i replaced the 3 ohm resistor with a few other resistors in series to get 3 ohms....powered it up and the current draw spiked up big time and the resistor got really hot..and the ps also started to make a wizzing sound.
...was it shorting that caused this and possibly the cause of my/our headache??
i cant see under the 5534 but im pretty sure it goes to pin 7, the v+ ....pin 7 used to read 0.000vdc <<<would this mean a direct short? since there is no +/- polarity?
now its at like 0.6 vdc....and the dc output on the speaker wires dropped down to 6 vdc from 10vdc
so you think its possible that these two components is what is causing the problem?
theres no value on the orange teardrop mylar, do you know the value? i have to run out and buy one tommorrow, is there a higher temperature alternative?
it was hell to get out of the board, i had to remove the surrounding caps so it wouldnt draw the heat away.
i think this is finally it !!!! 😀 😀 😀
------------------------------------------
i wasnt sure of the current draw, because with it in the needle stays right below 10 amps but with it out, it rides just on 10amps..will buy a more sensitive ammeter.
ps...the regulated voltage in the picture in post 57 is constant throughout.
the 3 ohm resistor to the immediate right of the 5534 in the orange channel, is bad, .....there is also a orange teardropped shape mylar cap that doesnt measure...they are both connected together.
this mylar cap is tied into the ground plane, with voltage coming in through the other leg via the 3 ohm resistor.
i replaced the 3 ohm resistor with a few other resistors in series to get 3 ohms....powered it up and the current draw spiked up big time and the resistor got really hot..and the ps also started to make a wizzing sound.
...was it shorting that caused this and possibly the cause of my/our headache??
i cant see under the 5534 but im pretty sure it goes to pin 7, the v+ ....pin 7 used to read 0.000vdc <<<would this mean a direct short? since there is no +/- polarity?
now its at like 0.6 vdc....and the dc output on the speaker wires dropped down to 6 vdc from 10vdc
so you think its possible that these two components is what is causing the problem?
theres no value on the orange teardrop mylar, do you know the value? i have to run out and buy one tommorrow, is there a higher temperature alternative?
it was hell to get out of the board, i had to remove the surrounding caps so it wouldnt draw the heat away.
i think this is finally it !!!! 😀 😀 😀
------------------------------------------
i wasnt sure of the current draw, because with it in the needle stays right below 10 amps but with it out, it rides just on 10amps..will buy a more sensitive ammeter.
ps...the regulated voltage in the picture in post 57 is constant throughout.
The teardrop capacitors are tantalum capacitors. They are known to short.
The amp should work without the cap in place. If you have an electrolytic of approximately the same value, you can use it as a temporary replacement.
If the tantalum cap was connected between the regulated B+ and ground. It would have caused the 2.7 ohm resistor to open. You can use your ohm meter to confirm that the tantalum was connected to pin 7.
These could both have caused the DC offset but I wouldn't expect them to cause excessive current draw. The regulator is limited to ~1 amp. Even if it was passing 1 amp, I wouldn't expect it to cause more than ~4-5 amps of draw from the power supply.
With the tantalum capacitor removed, does the amp draw excessive current? If so, how much?
The amp should work without the cap in place. If you have an electrolytic of approximately the same value, you can use it as a temporary replacement.
If the tantalum cap was connected between the regulated B+ and ground. It would have caused the 2.7 ohm resistor to open. You can use your ohm meter to confirm that the tantalum was connected to pin 7.
These could both have caused the DC offset but I wouldn't expect them to cause excessive current draw. The regulator is limited to ~1 amp. Even if it was passing 1 amp, I wouldn't expect it to cause more than ~4-5 amps of draw from the power supply.
With the tantalum capacitor removed, does the amp draw excessive current? If so, how much?
8.65vdc/1.1 ohm =7.86 amps
(i changed the resistor to bigger higher wattage 1.1 ohm)
i just checked the speaker output and it is now .045vdc
pin 7 on the 5534 is now also getting 13 volts !!! 🙂
the fets in the ps are pretty chewed up, one day i gave power to it out of the sink so i could feel the heat individually , and there are some getting hotter than others, one broke off too.
(i changed the resistor to bigger higher wattage 1.1 ohm)
i just checked the speaker output and it is now .045vdc
pin 7 on the 5534 is now also getting 13 volts !!! 🙂
the fets in the ps are pretty chewed up, one day i gave power to it out of the sink so i could feel the heat individually , and there are some getting hotter than others, one broke off too.
i cant be sure of the value of the cap, you know the value? thers no specs on it.
its not one of the disc shaped ones its a teardrop, i thought it was a mylar....oh well...learn somethig new.
its not one of the disc shaped ones its a teardrop, i thought it was a mylar....oh well...learn somethig new.
The current draw is still excessive.
Were the jumpers in place when you measured the voltage across the 1.1 ohm resistor?
If not, replace them and check the current draw again. If they were in place, jump the other two diodes and recheck the current draw.
The cap is a 2.2uf. You'll need one rated for at least 16v. I'd suggest a 25v if you're going to replace it with another tantalum.
Were the jumpers in place when you measured the voltage across the 1.1 ohm resistor?
If not, replace them and check the current draw again. If they were in place, jump the other two diodes and recheck the current draw.
The cap is a 2.2uf. You'll need one rated for at least 16v. I'd suggest a 25v if you're going to replace it with another tantalum.
Sorry to go off topic, but i have a question for you Clipped.
I came across a post of yours stating that you own a pioneer cd-1000 crossover. do you happen to still have this item? im curious because i have this same crossover and am having problems with it. I cant seem to get decent out put from it without clipping the crap out of it.
I came across a post of yours stating that you own a pioneer cd-1000 crossover. do you happen to still have this item? im curious because i have this same crossover and am having problems with it. I cant seem to get decent out put from it without clipping the crap out of it.
well, had a little mishap, tried playing music through the amp and now theres no ac coming through to the secondaries, and started pulling crazy current afterwards...
checked the fets 3 are dead...will fix before moving on, i really have to do something about those diodes underneath.
internecine, i stil have that crossover, but its not working, the output for that unit is only 500milivolts.
checked the fets 3 are dead...will fix before moving on, i really have to do something about those diodes underneath.
internecine, i stil have that crossover, but its not working, the output for that unit is only 500milivolts.
any amp will work with it, maybe just not to its full potential...
a line driver would do wonders for it...its a good crossover.
it actually cuts the frequencies where it says it will.
what kind of headunit you got?
audiocontrol has a 6 channel linedriver called the 'Matrix' which would be perfect for it...
a line driver would do wonders for it...its a good crossover.
it actually cuts the frequencies where it says it will.
what kind of headunit you got?
audiocontrol has a 6 channel linedriver called the 'Matrix' which would be perfect for it...
are there only certain amps that will work with this amount of out put? would a line driver after the crossover help?
im using my stock HU, the stock HU has pre outs which i run to the cd-1000.
im just about to get rid of the thing because i cant get any sort of devent volume out of it. although i really want to keep it, like you said, its an amazing piece of equipment.
when i run the RCAs straight to the amp the volume level is great, even with the gains at the minimum. but when run through the CD-1000 i have to crank the gains on the amp. even then i dont get much output.
ive played with the input and output levels on the CD-1000 and i get nothing usable. Ive tried a audiocontrol EQL with line driver before the CD-1000 and that didnt help anything. So i guess i could try the EQL after the CD-1000, if that works, then i could get a line driver for each channel, but that seems silly, i would need a 14 channel line driver for this thing if i used it for 3-way front, rear and sub.
btw, thanks for helping
im just about to get rid of the thing because i cant get any sort of devent volume out of it. although i really want to keep it, like you said, its an amazing piece of equipment.
when i run the RCAs straight to the amp the volume level is great, even with the gains at the minimum. but when run through the CD-1000 i have to crank the gains on the amp. even then i dont get much output.
ive played with the input and output levels on the CD-1000 and i get nothing usable. Ive tried a audiocontrol EQL with line driver before the CD-1000 and that didnt help anything. So i guess i could try the EQL after the CD-1000, if that works, then i could get a line driver for each channel, but that seems silly, i would need a 14 channel line driver for this thing if i used it for 3-way front, rear and sub.
btw, thanks for helping
yeah id get rid of it, i think the solder is getting down to past its usefull life...i cracked mine open and the solder looked stale and dehydrated, really strange....it is a pretty old piece.
Perry Babin said:
i changed those zeners out with fresh ones, replaced the tantulum with same value, and put in a 1/2 watt 3 ohm resistor, in place of the bad one.
the current is down to normal now after changing those fets.
with resistor in place:
1.25vdc/ 1.1ohm = 1.13 amps
(with the resistor removed it also looks normal now)
it shut down because i tested it without the resistor with music.
(i'll admit it) prior to changing them the current was excessive.
-------------------------------------------------------------------
the sound was scratchy so i changed the pot, but too 100k, since this was all i had, other than 250k and 10k...will i be losing volume because of this 100k?
right now i have 3 different fets in the ps ..
15= smp60n06
2=IRFZ44n
1=ssp60n06
i will change them once this thing is debugged.
one strange thing, the fets on the yellow side run cooler than the other bank.
anything i should check out before i take the resistor off the B+ and test it full tilt?
im listening to it right now with power resistor in place bridged mono @4 ohms...for around 40 minutes now.
yea, i turn those up 1/4 way, any more than that and the clipping light starts flashing and the speakers start distorting
i want this thing to work so badly. but i dont think thats going to happen
i want this thing to work so badly. but i dont think thats going to happen
when i opened mine up, most of the capacitors were bad and leaking, especially the ones in the power supply and the electrolyte was starting to eat through the board.
on the outputs there are A56/06 pairs for each channel used for output...by the rca jacks, its a long shot but maybe theyre starting to go...i found a couple on this one that had cracked solder joints.
taking this thing apart is no fun man...they used really cheap solder on these guys, get rid of it.
on the outputs there are A56/06 pairs for each channel used for output...by the rca jacks, its a long shot but maybe theyre starting to go...i found a couple on this one that had cracked solder joints.
taking this thing apart is no fun man...they used really cheap solder on these guys, get rid of it.
- Status
- Not open for further replies.