Hi,
I have a Rubicon 5.2 which otherwise appears to be working flawlessly, but I´ll try to describe what happens when the remote wire is connected.
Usually, these amps will immediately draw a little current when the remote wire is connected, and after a second or two will idle.
With this one, the needle of the analogue indicator of our power-supply goes back and forth between 0 and 1 ampere (approx.) 3 or 4 times before idling normally at just under 1.5 ampere.
It makes me think of the kickstarter of a motorcycle, where you´d have to kick a couple of times before the engine turns on.
I´d say the turn-delay is pretty normal, about two seconds or so. So the back and forth going of the needle happens within this time-frame.
Any ideas ?
I have a Rubicon 5.2 which otherwise appears to be working flawlessly, but I´ll try to describe what happens when the remote wire is connected.
Usually, these amps will immediately draw a little current when the remote wire is connected, and after a second or two will idle.
With this one, the needle of the analogue indicator of our power-supply goes back and forth between 0 and 1 ampere (approx.) 3 or 4 times before idling normally at just under 1.5 ampere.
It makes me think of the kickstarter of a motorcycle, where you´d have to kick a couple of times before the engine turns on.
I´d say the turn-delay is pretty normal, about two seconds or so. So the back and forth going of the needle happens within this time-frame.
Any ideas ?
If it's in working order I just wouldn't care about it.
My Atlas VIII and my Saturn Gen.X even make my headlights dim for a split second when they turn on.
First the Saturn and then the Atlas.
And my electrical system is strong enough to keep voltage steady under load, so it's most probably just the inrush current of the secondary capacitors.
What kind of (ampéres) power supply are you using?
My Atlas VIII and my Saturn Gen.X even make my headlights dim for a split second when they turn on.
First the Saturn and then the Atlas.
And my electrical system is strong enough to keep voltage steady under load, so it's most probably just the inrush current of the secondary capacitors.
What kind of (ampéres) power supply are you using?
On the test bench you mean ? It's an adjustable power supply, the analogue indicator shows up to 3 ampere.
I've never had problems with this power supply before, there's definitely something not quite right with the amp.
Yes I thought about putting it in the car, but my father thinks this problem should not be very hard to solve (he could be wrong of course) so we'll probably have a look at it.
I've never had problems with this power supply before, there's definitely something not quite right with the amp.
Yes I thought about putting it in the car, but my father thinks this problem should not be very hard to solve (he could be wrong of course) so we'll probably have a look at it.
Of course they are not true Class A amps.
The older Soundstream high bias amps (such as Class A 6.0) idled much, much higher, but that resulted in heat issues. Therefore, for the later models they dropped the bias drastically.
I agree with you that at such a low amperage, one can barely even call it a high bias amp. But the internals are technically similar to the older high bias models and different to the non-high bias models, and they sound great to me.
The 1 ampere while starting up does not concern me, what concerns me is that the needle goes back and forth between 0 and 1 ampere three or four times before idling at 1.5 ampere. The back and forth going is what is not normal.
Thanks for your input,and I agree I could put it in the car, but chances are it will be defective at some point as a small problem often is the beginning of larger problem, if not attended to.
The older Soundstream high bias amps (such as Class A 6.0) idled much, much higher, but that resulted in heat issues. Therefore, for the later models they dropped the bias drastically.
I agree with you that at such a low amperage, one can barely even call it a high bias amp. But the internals are technically similar to the older high bias models and different to the non-high bias models, and they sound great to me.
The 1 ampere while starting up does not concern me, what concerns me is that the needle goes back and forth between 0 and 1 ampere three or four times before idling at 1.5 ampere. The back and forth going is what is not normal.
Thanks for your input,and I agree I could put it in the car, but chances are it will be defective at some point as a small problem often is the beginning of larger problem, if not attended to.
Do you have a bigger PS for testing?
If your PS has a current limiter, is it set open?
Pull the fuses, put a 10A in there and start it up again.
Perhaps it's the small PS that's breaking down too much, so the SMPS from the SS can't start up at the first try, while charging the secondary caps.
Goede nacht!
If your PS has a current limiter, is it set open?
Pull the fuses, put a 10A in there and start it up again.
Perhaps it's the small PS that's breaking down too much, so the SMPS from the SS can't start up at the first try, while charging the secondary caps.
Goede nacht!
I don't have a bigger PS, I do have a fully charged large battery but I wouldn't be able to read the current draw.
Again, I have hooked up all kinds of amps to this power supply, including most of the amps Soundstream made in that era, including the almost identical but larger 10.2, and never experienced this.
It would therefore truly amaze me if the PS is causing this.
Again, I have hooked up all kinds of amps to this power supply, including most of the amps Soundstream made in that era, including the almost identical but larger 10.2, and never experienced this.
It would therefore truly amaze me if the PS is causing this.
I forgot we have a certain digital multimeter with which one can read current draw, by wiring it in series with the power wires going to the amplifier.
So we checked whether the amplifier acted the same on our power supply as on our fully charged battery, and it did. Definitely not the power supply, definitely something wrong with the amplifier.
During startup, we found irregular voltage on pins 2, 9, 11, 14 and 15. Accroding to my father, pins 12 and 13 are on the same circuit as pin 15 so it should be the same there.
We measured with the oscilloscope, so numberaren't as accurate as with the DMM:
pin1 2.6 V
pin2 2.1 V irregular voltage at first
pin3 3.2 V but it was not typical DC, not AC either though
pin4 0 V according to my father, I didn't see though
pin5 same as pin4
pin6 3 V
pin7 3 V but it was not typical DC, not AC either though, and it had some DC offset.
pin8 same as pin4 and 5
pin9 3 V irregular voltage at first
pin10 not in use
pin11 14V irregular volateg at first, and I think it also had neither typical DC nor AC
pin12 should be the same as 15 according to my father
pin13 same as 13 and 15 according to my father
pin14 14 V irregular voltage at first and I think it also had neither typical DC nor AC
pin15 16 V (not 15V ?! though didn't check with DMM so not accurate) irregular voltage at first
pin16 4.9 V
So we checked whether the amplifier acted the same on our power supply as on our fully charged battery, and it did. Definitely not the power supply, definitely something wrong with the amplifier.
During startup, we found irregular voltage on pins 2, 9, 11, 14 and 15. Accroding to my father, pins 12 and 13 are on the same circuit as pin 15 so it should be the same there.
We measured with the oscilloscope, so numberaren't as accurate as with the DMM:
pin1 2.6 V
pin2 2.1 V irregular voltage at first
pin3 3.2 V but it was not typical DC, not AC either though
pin4 0 V according to my father, I didn't see though
pin5 same as pin4
pin6 3 V
pin7 3 V but it was not typical DC, not AC either though, and it had some DC offset.
pin8 same as pin4 and 5
pin9 3 V irregular voltage at first
pin10 not in use
pin11 14V irregular volateg at first, and I think it also had neither typical DC nor AC
pin12 should be the same as 15 according to my father
pin13 same as 13 and 15 according to my father
pin14 14 V irregular voltage at first and I think it also had neither typical DC nor AC
pin15 16 V (not 15V ?! though didn't check with DMM so not accurate) irregular voltage at first
pin16 4.9 V
Does B+ stand for battery + ?
Any guess as what could cause this ? Do I need to do something about it ?
We checked here and there, using the schematics, but we have no clue.
Remember that 10.2 with the extremely long turn-on the delay ? Still in my car, still no problems, while we did not repair it I believe. Strange.
Got another 10.2 with very strange behaviour, haven't had the guts to look at that one yet, an older thread of mine. That amp scares me, I am always afraid of powering it up to do some measurements as I am afraid its behaviour might be damaging to itself, which might be totally stupid...
Any guess as what could cause this ? Do I need to do something about it ?
We checked here and there, using the schematics, but we have no clue.
Remember that 10.2 with the extremely long turn-on the delay ? Still in my car, still no problems, while we did not repair it I believe. Strange.
Got another 10.2 with very strange behaviour, haven't had the guts to look at that one yet, an older thread of mine. That amp scares me, I am always afraid of powering it up to do some measurements as I am afraid its behaviour might be damaging to itself, which might be totally stupid...
Does B+ stand for battery + ?
**** Yes. The voltage across the positive and ground terminals.
Any guess as what could cause this ?
**** The battery voltage depends on the current draw. When the amp powers up, there is a surge of current that causes the voltage to drop a bit.
Do I need to do something about it ?
**** There isn't anything you can do about it. All amps will cause this to happen to some degree.
**** Yes. The voltage across the positive and ground terminals.
Any guess as what could cause this ?
**** The battery voltage depends on the current draw. When the amp powers up, there is a surge of current that causes the voltage to drop a bit.
Do I need to do something about it ?
**** There isn't anything you can do about it. All amps will cause this to happen to some degree.
That's that, then.
I'll just re-assemble it, polish it and put it in my car and put it to good use.
I'll get the 10.2 out of there and put it for sale, gonna keep the 5.2 as I've got 2 spare boards from Jaime, for this amp.
Haven't seen an amp do this, though. Must be some kind of repairable malfunction, no ?
I was thinking of replacing the SG3524 chip a couple of weeks ago, but it could be so many different things causing this. Maybe a capacitor ?
I'll just re-assemble it, polish it and put it in my car and put it to good use.
I'll get the 10.2 out of there and put it for sale, gonna keep the 5.2 as I've got 2 spare boards from Jaime, for this amp.
Haven't seen an amp do this, though. Must be some kind of repairable malfunction, no ?
I was thinking of replacing the SG3524 chip a couple of weeks ago, but it could be so many different things causing this. Maybe a capacitor ?
I have purchased nice switching power supplies last week. They are 13.8 V 25A continuous fan cooled.
But I think there is something wrong with this particular amplifier to cause this strange behaviour, I mean no other amp I have has ever done this, not even the very similar 10.2
Hmm, I could unpack one of the 5.2 boards I purchased from Jaime and power it up, then we'll know whether this is normal behaviour for this particular model or not. I would be surprised if another board shows the same behaviour. Only one way to find out.
I'll let you know what happens when I power on one of the two other 5.2 boards I have.
But I think there is something wrong with this particular amplifier to cause this strange behaviour, I mean no other amp I have has ever done this, not even the very similar 10.2
Hmm, I could unpack one of the 5.2 boards I purchased from Jaime and power it up, then we'll know whether this is normal behaviour for this particular model or not. I would be surprised if another board shows the same behaviour. Only one way to find out.
I'll let you know what happens when I power on one of the two other 5.2 boards I have.
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