I left the amp on for about 4 hours and the amp has not protected i detected it goes to protection when the chip is Hot and i touch the board, with no touching the board tje amp stay green ligth an rail voltages in -85 and +85
Email me auction numbers so no one here can buy it before you do.
babin_perry@yahoo.com
Side note, a 2mhz scope in good working order is good enough. A comparison between the 2 and 100M scope is on the basic repair page. The waveforms are essentially identical.
babin_perry@yahoo.com
Side note, a 2mhz scope in good working order is good enough. A comparison between the 2 and 100M scope is on the basic repair page. The waveforms are essentially identical.
Thank you is the same model scope of ebay, but i Will buying from a person in my city.
Thank you
Thank you
The auction numbers are to see if the scope appears to be in good working order. I can't tell that from a different scope.
Thank you Bl4k Widow!, i apreciate your note, its easier to check first CL1,did you measure the CL1value in the board or you desoldier it from the board?
Perry i lost the deal when i was driving to the house of the seller,some one arrive first and bougth it.
I think i lost a very good deal, i was going to pay 20 us dollar for that scope.
I think i lost a very good deal, i was going to pay 20 us dollar for that scope.
I pulled it. I only check caps on the board for shorts. If I suspect something then I pull it and check it. You cant normally check caps in circuit and get a definitive answer.
When you pull the chip out of the board, should i use heat gun or normal Cautín? , and When you install the New one, what method you use? When i read your lasts answer i asume you use normal Cautín, but i,m not shure about it.
i m back again with this amp, now that i got the owon scope, can you comment what do you think i posted a pic from the signal of the psu i do not see a problem with it.
ihave +85 and minus 85 volts in rails i
In the output section i got
in the negative rail gate=-85.3 volts drain 0,03 volt and source -85.7
positive rail gate=-0.4 volts Drain =85.8 volts source 0.034 volts
the values are with no mosfets installed
i injected a sine wave 40 hz in the audio input in attemp to start oscillation, with no succes
i tried to measure switching signal , there is no signal in the gates i measure other pins and got only the dc voktage of the rails in the pins a said before
i think the next step is replace the switching Ic.
regards
ihave +85 and minus 85 volts in rails i
In the output section i got
in the negative rail gate=-85.3 volts drain 0,03 volt and source -85.7
positive rail gate=-0.4 volts Drain =85.8 volts source 0.034 volts
the values are with no mosfets installed
i injected a sine wave 40 hz in the audio input in attemp to start oscillation, with no succes
i tried to measure switching signal , there is no signal in the gates i measure other pins and got only the dc voktage of the rails in the pins a said before
i think the next step is replace the switching Ic.
regards
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something weird is happening, i inject the 40 hz signal and i am able to trace it a the pin 5 of the 4558d with the amp off, but as soon as i turn on the amp i lost that signal, instead i got oscilation between 300 to 1 khz, tihs strange signal is present at the input rcas, it seems that this signal overlap the 40 hz signal, when i turn off the amp the 40 hz is there, the same with the channel Rigth i trace the signal and is present in pin 3 of the same op amp, but i lost it with the amp is on.
Between 12v.negative. And secondary ground (I understand secondary ground as the point where te negative. Of the positive rail joins with the positive of the negative rail). I tried to explain in case I made a mistake. The r=. 1 kohm
If you measure the primary to secondary resistance to be 1k ohms, you should be able to use either ground.
Back to the devices in red. What are the numbers on their faces?
Back to the devices in red. What are the numbers on their faces?