ZAAAAP!!!
fried
I have no idea what happened... but I'm glad I only hooked them up one at a time
everything's perfect... so with the last 5 boards I have I'm going to be way more careful
only one question...
the AC1 with a line over it is neutral right??? and the AC1 without a line is the hot wire correct
lol jesus can't believe it fried.... it only did this once I hooked the input and outputs up though
fried
I have no idea what happened... but I'm glad I only hooked them up one at a time
everything's perfect... so with the last 5 boards I have I'm going to be way more careful
only one question...
the AC1 with a line over it is neutral right??? and the AC1 without a line is the hot wire correct
lol jesus can't believe it fried.... it only did this once I hooked the input and outputs up though
Re: Re: LOL.... I just fried 3 of my brianGT LM4780 boards
I don't think so...
I didn't hook up speakers... never even got to that point
I'm pretty sure I did
but that's why I asked... what is the AC1 with line over it mean on the rectifier board.... the AC1 without it???? and the AC2 etc
as far as from the wall to the xfrmer it's right now with hot and cold wires
so.... yea I"m pretty damn sure that far is right
what would cause the chip casing to explode?
on 2 chips... but no other components do anything or even smoke?
carlosfm said:
I don't think so...
I didn't hook up speakers... never even got to that point
I'm pretty sure I did
but that's why I asked... what is the AC1 with line over it mean on the rectifier board.... the AC1 without it???? and the AC2 etc
as far as from the wall to the xfrmer it's right now with hot and cold wires
so.... yea I"m pretty damn sure that far is right
what would cause the chip casing to explode?
on 2 chips... but no other components do anything or even smoke?
While you're at Home Depot, ask the nice electrical man for a light bulb socket you would normally hang from the ceiling (the cheapest one they have is perfect), and a box to put it in. Also buy 40W, 100W and the biggest watt bulb you can find. And buy a "stove fuse", about 10A. Get one that can screw into the lamp socket.
Wire the lamp socket in series with your amp's AC in. On the hot lead. That's the black wire, bronze screw connection.
Try the PSU with lowest-to-highest watt bulbs before finally connecting it to the amp, and measure the darn thing to make sure it's working right (input and output voltage should be proportional).
Then pop in the fuse instead of the bulb (full power) and make sure your values are correct on the output rails. NO MORE than 39VDC! Also, make sure no parts are getting ridiculously hot.
Next, repeat the exercise above with the amplifier connected to the PSU -- with a 100W bulb, I would not expect it to glow when the amp is idle! (Actually, I'd be shocked if the 40W bulb glowed while the amp was idle). Note that the amp may not work if the lightbulbs aren't high enough powered, but you should still be able to measure your circuit with the low watt bulbs to make sure your connections, etc, are good. I'm GUESSING that the amp will work okay (albeit quitely) with a 100W bulb, assuming you're running reasonably macho rails (28V or better).
The light bulbs will work as current limiters, and the more power your circuit requires, the brighter they will glow. This is why a brightly glowing bulb with an idle amp is a bad sign -- it should only be drawing power when either under load OR the caps are charging OR the transformer is energizing. Running your amp for the first time through a light bulb is a great way to avoid blowing things up.
Incidentally, you have proven the old adage -- only a rich man can afford cheap tools.
Wes
Wire the lamp socket in series with your amp's AC in. On the hot lead. That's the black wire, bronze screw connection.
Try the PSU with lowest-to-highest watt bulbs before finally connecting it to the amp, and measure the darn thing to make sure it's working right (input and output voltage should be proportional).
Then pop in the fuse instead of the bulb (full power) and make sure your values are correct on the output rails. NO MORE than 39VDC! Also, make sure no parts are getting ridiculously hot.
Next, repeat the exercise above with the amplifier connected to the PSU -- with a 100W bulb, I would not expect it to glow when the amp is idle! (Actually, I'd be shocked if the 40W bulb glowed while the amp was idle). Note that the amp may not work if the lightbulbs aren't high enough powered, but you should still be able to measure your circuit with the low watt bulbs to make sure your connections, etc, are good. I'm GUESSING that the amp will work okay (albeit quitely) with a 100W bulb, assuming you're running reasonably macho rails (28V or better).
The light bulbs will work as current limiters, and the more power your circuit requires, the brighter they will glow. This is why a brightly glowing bulb with an idle amp is a bad sign -- it should only be drawing power when either under load OR the caps are charging OR the transformer is energizing. Running your amp for the first time through a light bulb is a great way to avoid blowing things up.
Incidentally, you have proven the old adage -- only a rich man can afford cheap tools.
Wes
I can't think of any obvious reason why you'd be blowing amplifier chips, but shorting one of your voltage rails to ground isn't one of them. Gross assembly error at the PSU or PSU->amp are the likely causes IMHO. Also check for solder bridges, correct orientation of ICs..
You should really read this: http://sound.westhost.com/troubleshooting.htm#tools
Actually, there's lots of good info on that site in general.
Disconnect the amp and PSU, and start your troubleshooting with the lamp lead at the PSU. Make sure it's good. THEN move onto the amp (after a careful visual inspection).
Wes
You should really read this: http://sound.westhost.com/troubleshooting.htm#tools
Actually, there's lots of good info on that site in general.
Disconnect the amp and PSU, and start your troubleshooting with the lamp lead at the PSU. Make sure it's good. THEN move onto the amp (after a careful visual inspection).
Wes
I built the amp perfectly actually.... exactly the way it's supposed to look etc
there are no solders touching or any such thing
checked it 1000000 times
there is no PSU to speak of for me to mess up on!
I'm working with it now... if I find out what it was I will post and then allow you all to give me the perpetual smack in the face
there are no solders touching or any such thing
checked it 1000000 times
there is no PSU to speak of for me to mess up on!
I'm working with it now... if I find out what it was I will post and then allow you all to give me the perpetual smack in the face
ok... I did it...
something seems very very wrong here... or am I missing something entirely???
I checked the voltages after the 25v 500VA dual secondary transformer... and this is what I'm getting
I put the + probe on the 25v and the - (black) probe on the 0v wires on one of the secondaries...
on the 50 setting ... it's ticking to right around 6.5 or 7 on the ACV scale...
I have no idea what this means... so yea.... the instructions basically sucked
but if I'm reading this right it's getting 58v from the outputs???
on the DC after the rectifier on the 50 setting... it's ticking to over where the AC did on that setting... but it's ticking to like 200 on the scale here...
I don't know what this means... I'm going to try some things while I wait for a reply
something seems very very wrong here... or am I missing something entirely???
I checked the voltages after the 25v 500VA dual secondary transformer... and this is what I'm getting
I put the + probe on the 25v and the - (black) probe on the 0v wires on one of the secondaries...
on the 50 setting ... it's ticking to right around 6.5 or 7 on the ACV scale...
I have no idea what this means... so yea.... the instructions basically sucked
but if I'm reading this right it's getting 58v from the outputs???
on the DC after the rectifier on the 50 setting... it's ticking to over where the AC did on that setting... but it's ticking to like 200 on the scale here...
I don't know what this means... I'm going to try some things while I wait for a reply
ok.... wired it to the amp board... 100w bulb is in...
the bulb is lit and stays lit.... I'm now measuring my voltages at the outputs...
why is it doing this?
the AC voltage at the outputs is either 2v with the bulb always on... or it's 8v...I still haven't figured this damn analog meter out 100%
the bulb is lit and stays lit.... I'm now measuring my voltages at the outputs...
why is it doing this?
the AC voltage at the outputs is either 2v with the bulb always on... or it's 8v...I still haven't figured this damn analog meter out 100%
I'm going to hook up the outputs... sense you state the amp should function with this bulb but not very well
in the 2 min or so I had this one the chip warmed up the alum sink signifcantly... which I feel isn't the way it should be... I think somethings wrong... but damn I put everything in 100% correct
this was without input BTW.... the amp was showing voltage on the outputs without any input at all
in the 2 min or so I had this one the chip warmed up the alum sink signifcantly... which I feel isn't the way it should be... I think somethings wrong... but damn I put everything in 100% correct
this was without input BTW.... the amp was showing voltage on the outputs without any input at all
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