Rebuilding another JL, this one blew only half the power supply FETs and a rectifier. It got so hot one of the bussbars fell off the board. Reinstalled that and cleaned everything up, but what are these 4 diodes doing in the circuit? One exploded, and I removed the other to get the part number off it. Do they need to be ultra fast, or are normal diodes good enough?
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I have 4 ultra fast to put in.
Did they H-bridge the power supply on this? Seems different than their other offerings.
Did they H-bridge the power supply on this? Seems different than their other offerings.
Interesting.
Does the output section work more or less the same as the 500 watt ones? In other words, can I boot up the standby supply and verify gate drives on the outputs in the same way as a 500/1?
Does the output section work more or less the same as the 500 watt ones? In other words, can I boot up the standby supply and verify gate drives on the outputs in the same way as a 500/1?
On at least some of the 1000s, you are limited to about 4 seconds of drive unless you bridge pins 6 and 7 on U517.
I have good gate drive to all output devices and the power supply as well. Put a pair of FETs into each side of the power supply and connected the remote wire, it tries to come online but then I hear a high pitched squeal and the low volt lamp flashes. I always use a current limited power supply for troubleshooting though, so it’s possible the 5 amps I’m working with isn’t enough to get this thing through the powerup inrush surge. I’m going to try something with a bit more a$$ to it when I get home, hopefully that does the trick and I’ll be able to pass some audio through it later today.
Most of the JL amps of this series have problems with the limiter. The 1000 is the amp I had to buy a battery for to run hard. I have enough power supply for most amps but the JL 1000 was so sensitive to dips in voltage that it wouldn't run at high power without a car battery.
Makes me wonder how these things blow up at all, I mean they seem designed pretty well and there's protection built into them. I don't think this one was abused at all, just looks like a random rectifier failure took it out.
RE: power supplies
If you need a good stiff power source for load testing, I figured out how to hack the converter from a Civic hybrid which gives you around 100 amps at 13VDC for power runs on large amplifiers. If I need to test something this size I'll use that and an 800 amp truck battery connected together, works pretty well and is cheaper than trying to buy a commercial supply that size.
RE: power supplies
If you need a good stiff power source for load testing, I figured out how to hack the converter from a Civic hybrid which gives you around 100 amps at 13VDC for power runs on large amplifiers. If I need to test something this size I'll use that and an 800 amp truck battery connected together, works pretty well and is cheaper than trying to buy a commercial supply that size.
Got it to come on line with an 8 amp power supply, idle is just shy of 3 amps and it looks OK to solder in all the power supply FETs. Are IRF3709Z’s a suitable replacement for the original NLA ones?
Power supply works but now I have the low ohm light, somehow I smoked an output FET. The originals are NLA but Mouser stocks STP40NF20 which looks like a viable candidate, see anything wrong with it? Original was 45n20.
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The newer models use FDP52N20 FETs with 22.1 ohm gate resistors. I don't know if the others will work.
Almost forgot to ask, what’s the name for this soft material attached to the transistor clamps? Some of it got burned up when the power supply let go, so I need to source some to replace it.
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