and wont start on fire ? So im beginning to wonder if the ic is bad on the a1266 board I havnt swapped that one yet with working 1000 also if I missed a resistor on the board somewhere is it possible that could cause the voltage to fluctuate or even the on board capacitors? I need to get me one of those meters for testing capacitors when I can afford one they seem pricey tho
When the FETs fail, they burn hot enough to melt aluminum. The cardboard is a non-issue.
Are you referring to the power supply driver board?
Capacitance meters aren't very expensive, but the accuracy for the cheaper ones isn't as good as better meters. Better meters allow calibration for the leads and have different test frequencies. If you buy a cheap one, buy a range of capacitors to use as a reference.
Are you referring to the power supply driver board?
Capacitance meters aren't very expensive, but the accuracy for the cheaper ones isn't as good as better meters. Better meters allow calibration for the leads and have different test frequencies. If you buy a cheap one, buy a range of capacitors to use as a reference.
Id rather just buy the best one I can buy when I decide to buy one with all the options I can get that is any suggestions?
That gives you a lot of options. Start a new thread for capacitance meter or LCR meter (if you want one that measures inductance) and post links to the ones you're interested in.
If you don't have a scope, that would be a MUCH better investment.
If you don't have a scope, that would be a MUCH better investment.
So you would suggest buying a scope instead of the cap meter ill beable to do a lot more repairs that way? I know there pricey and for a good one what kind of money will I need to spend you think?
You can buy a good used scope for less than $200.
Email me. I don't want to post a link to a scope and have someone else buy it.
babin_perry@yahoo.com
Email me. I don't want to post a link to a scope and have someone else buy it.
babin_perry@yahoo.com
Update replaced the irf3205 fets with P50n06 fets and the gate resistors with the same results theres a pulsing sound coming from the sub and the ohms on the speaker channel fluctuating from 0-68ohm back down to 0-68ohm constantly checked the op amps near the rca jacks 8 pin with the same result the voltage is fluctuating alittle lost whether or not if a shorted capacitor could be causing this issue as we have confirmed all the riser boards are not the issue also noticed the irf640 and the irf9640's running warm within the 5 minutes I was running the amp to test voltages throughout the board
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Using the meter set to ohms isn't going to provide any useful information when power is applied since it's going to mean something different for every meter.
What happens if you power it up without the audio driver board (in front of the output transistors)?
What happens if you power it up without the audio driver board (in front of the output transistors)?
The grn led light stays lit and doesn't pulse on and off like the amp does with board installed the speaker doesn't make noise and there's no voltage fluctuation but I have already tried other riser boards with the same result it just seems like there's something simple I am missing here I thought for sure the p50n06 would have resolved the problem when comparing datasheets to the irf3205's which that's what everyone tells me what was originally in this amp was the p50n06 fets
Tested the voltage on the main board where the connector is B+ Steady 12.2 rem 12.2 both sets of pins for powering the board also the grn light doesn't light when powered up without the board the relay just clicks at first when being powered
you had me try swapping that board as well after I was having the issue I am having now before I messed with that board I had to remove the glue as well so I am assume that board has never been touched until I removed it
If I pull either the board next to the irf9640/irf640 hestsink rail or the board near the rca jacks the grn light will stay on and not pulse
Also I tried testing the voltage at the connector you have pictured at 60+ and ground both sides of the connector and the meter reads 0.00 and goes to OL not sure if that means open loop or Overload
Also I tried testing the voltage at the connector you have pictured at 60+ and ground both sides of the connector and the meter reads 0.00 and goes to OL not sure if that means open loop or Overload
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If you swapped all boards from a working amp and that didn't solve the problem, the problem appears to be on the main board. If there are no defective components and the board is undamaged, what's left? That's why I recommended checking the connectors.
I'm assuming that all power supply voltages are present.
I may re-recommend various things. I don't have the patience to re-read every post and can't remember the specifics. I've likely worked with 100+ repairs since this one.
I'm assuming that all power supply voltages are present.
I may re-recommend various things. I don't have the patience to re-read every post and can't remember the specifics. I've likely worked with 100+ repairs since this one.
That was my guess the problem is on the main board but it just don't see anything that could be remotely close to being burned and replaced all resistors tied into the power fets the only ones I havnt replaced are all resistors inline with all irf9640 and irf640 that's why I wonder if there could be some defective capacitors in the power section because it doesn't seem to act up until the amp fully charges capacitors when first being powered
Ill thoroughly check all connectors ive worked on 9 of these Memphis amps and this one is the only one that seems to be causing me problems thrown a lot of new parts at this one without any luck compared to all the others thanks again perry for your time
Ill thoroughly check all connectors ive worked on 9 of these Memphis amps and this one is the only one that seems to be causing me problems thrown a lot of new parts at this one without any luck compared to all the others thanks again perry for your time
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