IT has been replaced no worries. Working on the driver card and will be replacing the IR2184, LM211 just in case but I also found the transistor labeled 6P to the right of the LM211 is measuring 24 ohm between the collector and emitter . Do you know the appropriate replacement parts for the smd transistor labeled 6p. A bit of research shows it as an N channel jfet but this fellow replaces it with BCX 71J E6433 just wanted a bit of advice before proceeding
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I have a few extras so for me just peace of mind lol. I should have all of the fets in next week. I will report back ! Thank you for the datasheet I was referring to this one before and it caused me to get some different readings.
So I got the driver card back in, along with the 4452's and the power section together partially enough supply rail voltage to test + - 167VDC . I am not getting a gate drive signal on the low side (I have referenced to GND and also to NEG rail right now the output fets are not fitted I want to make sure I have low side drive before . Referenced to negative rail I am getting 12v on the TC442 VCC , and 12v on the IR2184. All the regulators are working correctly I have 12v for the drivers, -+ 12 for the preamp section and op amps. Is there something that I am missing ? Any help would be greatly appreciated.
DCV on pin 7 of the TL072 on the driver board?
Are you sure that it's the low-side drive that's missing out of the 2184 driver IC?
Are you sure that it's the low-side drive that's missing out of the 2184 driver IC?
Ugh accidentally blew one of the TC4452 drivers probing around. Will have to order extras also remove the driver card , should I check the pins leading to the driver card while i have it removed? Also should I be probing around referend to GND or the - Rail ? Thanks perry a bit frustrated :/
For an amp with positive and negative rail voltage, the 2184 is all referenced to the negative rail. The preamp circuit is referenced to ground. The transition point in the circuit is at Q2.
Ok thanks just wanted to confirm my findings. Reference to neg rail there is no low side gate drive at the 2184 and after the TC4452s on the mosfet gate pads. When inputing a 40hz test tone via the rca I did see a 40hz tone on the gate pads of the mosfets. I'll check voltage on pin 7 of the TL072. Any thing else I should look at?
Not yet.
What are you probing with? Scope, multimeter?
If scope, battery powered or mains powered?
What are you probing with? Scope, multimeter?
If scope, battery powered or mains powered?
Tested the vcc on the IR2184 and TC 4452 with multimeter. Checked for lowside drive with oscilloscope powered by mains , and also tested with handheld oscilloscope. Amp is being powered by lab bench powered supply.
As long as you don't try grounding the mains powered scope to the negative rail, you'll be OK. To check 2184 waveforms, you need to either use the handheld scope or your mains scope in differential mode.
Okay I will recheck with handheld scope just to be sure. need to wait for new TC4452 but can test the drive signal from the 2184 again. Also I will be shooting you an email to inquire about purchasing your amp repair tutorials! Thank you i will post more updates tomorrow.
You'll need to install the two browsers and other files mentioned on the top of the following page. It's far more than most are willing to do.
https://www.bcae1.com/temp/!_READ-ME_if_you_want_to_view_the_Flash_files.htm
https://www.bcae1.com/temp/!_READ-ME_if_you_want_to_view_the_Flash_files.htm
With the driver card out I did some probing and recorded voltages on the driver car pins:
Pin 1: SD signal for 2184 (3.4v ) on this pin
Pin 2: IRS2184 Com/VSS 0.0v
Pin 4: 12.1v + (referenced to negative rail / com )
Pin 9: GND for TL072 & lm211
Pin 12: 12.1v - (LM7812 output)
Pin 13: 12.1v + (LM7912 output)
Both Pin 12 and 13 feed power into the LM211, and the TL072
Its so strange no drive wave on the LO of the 2184 probed this with negative rail as a reference (o scope negative probe) with the battery powered oscilloscope, no matter time division/ voltage Div I couldn't locate a drive signal. , will check Pin 7 on the TL072 next, when checking this pin did you want me to reference to ground ?
Pin 1: SD signal for 2184 (3.4v ) on this pin
Pin 2: IRS2184 Com/VSS 0.0v
Pin 4: 12.1v + (referenced to negative rail / com )
Pin 9: GND for TL072 & lm211
Pin 12: 12.1v - (LM7812 output)
Pin 13: 12.1v + (LM7912 output)
Both Pin 12 and 13 feed power into the LM211, and the TL072
Its so strange no drive wave on the LO of the 2184 probed this with negative rail as a reference (o scope negative probe) with the battery powered oscilloscope, no matter time division/ voltage Div I couldn't locate a drive signal. , will check Pin 7 on the TL072 next, when checking this pin did you want me to reference to ground ?
Also no worries regarding comment #53 the effort is worth it, I read the page and will shoot an email over in the next couple days.
The TL072 is referenced to ground.
Regarding #53. I help everyone the same, regardless of their purchase of the tutorial. The difference is that I can often point them to sections covering various questions and they will get far more information.
Regarding #53. I help everyone the same, regardless of their purchase of the tutorial. The difference is that I can often point them to sections covering various questions and they will get far more information.
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OK I am reading 0 DCV on pin 7 of the TL072 when referenced to GND. Sorry if it came across that I thought that, I just finally have the funds to put into my hobbies, I recall coming across the BCAE1 website a few years ago and did not put 2 and 2 together until recently lol.
Do you have a square wave swinging ±5v on the output of the LM211? You may have to drive a strong signal into the amp to get a signal.
Do you have a square wave on pin 1 of the 2184? Amplitude?
Do you have a square wave on pin 1 of the 2184? Amplitude?
With no signal going into the amp no square wave on pin1 also nothing on pins 1 and 7 of the lm211. The best I have to inject a signal is a tablet
