I don't really see a problem with that drive. The falling edge is sharp and clean. The amplitude it low, however.
Set your power supply to exactly 12v and touch your probe to the positive terminal. Post a photo of the trace.
Set your power supply to exactly 12v and touch your probe to the positive terminal. Post a photo of the trace.
There is a transistor marked 2Q by the transformer can I sub it with something for testing ?
I still get 8 volts with the jumper removed on the gate legs of That bank of fets and also 8 volts on the emitters of the 2Q transistors and the 06. Q2003,2005
I still get 8 volts with the jumper removed on the gate legs of That bank of fets and also 8 volts on the emitters of the 2Q transistors and the 06. Q2003,2005
If the drive signal you posted is representative of all of the drive signals, I don't think you have any problems in the drive circuit. Without the jumper, the feedback loop is open and the drive signals won't be anywhere near normal.
So I should remove the jumper desolder the center legs of rectifiers and clamp everything down and monitor the current draw and see if the outputs in that bank get to hot ?
Amp is up and playing on bench I don’t notice any heating after 5 mins .
How long Should I let this play in the bench for the burn in period
How long Should I let this play in the bench for the burn in period
Most people won't test like I did. I had a lot of things to do other than repairs so I gave a lot of time to testing. It was common to let amps idle or play at very low power for an hour or so. It didn't often reveal problems but it did enough times to make it worth the time.
For high power testing, I drove the amp into intermittent clipping with bass music for about 3 hours into dummy loads that were 2x the minimum (2 ohms for 1 ohm amplifiers). This is mainly for class D amps.
For class B/AB amps, I ran the amps to thermal. Let them cool and come back on with the amp still driving the load.
For all amps, I let them cool completely and rechecked them before they left the shop.
For high power testing, I drove the amp into intermittent clipping with bass music for about 3 hours into dummy loads that were 2x the minimum (2 ohms for 1 ohm amplifiers). This is mainly for class D amps.
For class B/AB amps, I ran the amps to thermal. Let them cool and come back on with the amp still driving the load.
For all amps, I let them cool completely and rechecked them before they left the shop.
Ok thanks for the info I greatly appreciate all of your help with this amp .
And I will look into getting a new scope since this one has no adjustment for the throng you were talking about.
And I will look into getting a new scope since this one has no adjustment for the throng you were talking about.
I've never seen a CRT scope that didn't have an astig adjustment.
If you get this one clear, it's going to be far better than most any of the LCD based scopes you will likely buy.
If you get this one clear, it's going to be far better than most any of the LCD based scopes you will likely buy.
Well that didn’t work . Amp played perfectly on the bench for 3 hrs .
Put it back in the car and it went into protection after 5 mins at low volume and it blew the outputs .
Put it back in the car and it went into protection after 5 mins at low volume and it blew the outputs .
Ok amp came back to me and I just opened it up .
It happened to me on the bench once but it has the same issue .
The power supply drivers keep blowing . All fets test good I triple checked them .
Do you have any ideas on why the power supppy drivers keep blowing ?
It happened to me on the bench once but it has the same issue .
The power supply drivers keep blowing . All fets test good I triple checked them .
Do you have any ideas on why the power supppy drivers keep blowing ?
The ones on the driver board AND the ones on the main board?
ALL of just for one bank.
Are the drive waveforms perfect at the FETs?
ALL of just for one bank.
Are the drive waveforms perfect at the FETs?
Just the ones on the main board . Q100,101,102,103. They blew before when it was here the first time I replaced them and it came back with same issue .
It did blow that bank of fets . Q1,2,3,4,5,6
So now it has blown the same bank of drivers twice .
Can I just use remote and ground and post a pic of the waveform on that bank ? Fets are out of that bank right now
It did blow that bank of fets . Q1,2,3,4,5,6
So now it has blown the same bank of drivers twice .
Can I just use remote and ground and post a pic of the waveform on that bank ? Fets are out of that bank right now
What are you soldering them in with?
The drive waveforms will be useless if they're not loaded by either a capacitor or the FETs.
The drive waveforms will be useless if they're not loaded by either a capacitor or the FETs.