I am new to electronics repair. A friend gave this to me so Im trying to fix it. I have read very good things about this amp.
I replaced the fuses inside the amp. I do not have a preamp but I do have a dj mixer so I connected my booth out to the 'in' on the amp. then connected one speaker to the right channel. After this I turned it on. At the moment the power light comes on and so does the left channel light. It did make a strange pop sound when first powered on. But then nothing. I tried the other channel still no sound.
I do notice the part ADCOM 72-2206-0-0 on one of the blue things (sorry...if anyone can point me to a site that I can learn some of the basics of electronics please do.) looks fried. I am including a pic of the unit.
Any help or is this dead? I kinda want to do this myself so any links to some sites that I can learn from would be greatly appreciated.
I replaced the fuses inside the amp. I do not have a preamp but I do have a dj mixer so I connected my booth out to the 'in' on the amp. then connected one speaker to the right channel. After this I turned it on. At the moment the power light comes on and so does the left channel light. It did make a strange pop sound when first powered on. But then nothing. I tried the other channel still no sound.
I do notice the part ADCOM 72-2206-0-0 on one of the blue things (sorry...if anyone can point me to a site that I can learn some of the basics of electronics please do.) looks fried. I am including a pic of the unit.
Any help or is this dead? I kinda want to do this myself so any links to some sites that I can learn from would be greatly appreciated.
Attachments
Are you referring to the part at the lower left of the picture?
The 'Blue thing' is a power supply filter capacitor. On top is a small PCB that looks discolored. I assume under that board (between the board and the blue BIG capacitor) is a resistor. It appears to be used to simply light the lamp at the front panel of the amplifier (orange and black wire)..
Its improbable that this would be the cause of the problem...
Cheers!
Clem
The 'Blue thing' is a power supply filter capacitor. On top is a small PCB that looks discolored. I assume under that board (between the board and the blue BIG capacitor) is a resistor. It appears to be used to simply light the lamp at the front panel of the amplifier (orange and black wire)..
Its improbable that this would be the cause of the problem...
Cheers!
Clem
Those "blue things" can kill you if you don't know what you're doing.
Seriously, repairing a 200 watt amp with high voltages takes some knowledge and test equipment (at a minimum, a DVM, a signal generator, and an oscilloscope). If you don't have these, I would strongly urge you to get some local help.
Seriously, repairing a 200 watt amp with high voltages takes some knowledge and test equipment (at a minimum, a DVM, a signal generator, and an oscilloscope). If you don't have these, I would strongly urge you to get some local help.
Hi rinsbag,
Clem is right. That discolouration is normal and not the cause of any of your problems.
One. Never, ever just replace the fuses and power up unless you have a lot more information. It's a good amp, don't kill it permanently.
Two. It's a big amp. Not exactly a beginners project. You need some test equipment to begin with, and a variac.
Three. I've had customers with mixers that have destroyed perfectly good amps because of the very poor quality of mixer. If yours was not expensive or a really good brand (lost track - too much junk out there), reconsider and pick up a preamp. For sure it'll sound better.
So how much knowledge or training do you have?
-Chris
Clem is right. That discolouration is normal and not the cause of any of your problems.
One. Never, ever just replace the fuses and power up unless you have a lot more information. It's a good amp, don't kill it permanently.
Two. It's a big amp. Not exactly a beginners project. You need some test equipment to begin with, and a variac.
Three. I've had customers with mixers that have destroyed perfectly good amps because of the very poor quality of mixer. If yours was not expensive or a really good brand (lost track - too much junk out there), reconsider and pick up a preamp. For sure it'll sound better.
So how much knowledge or training do you have?
-Chris
Yes, stay away from those blue things. Note* They can also be white or black. If their big leave them B.
This is kinda like a big red wire in a television set for me. If I get with in a foot of one I get shocked.
Final note* Just sent the Adcom to me.
This is kinda like a big red wire in a television set for me. If I get with in a foot of one I get shocked.
Final note* Just sent the Adcom to me.
Hmm, I keep forgetting to warn people about opening up powerful amps; good thing there are many others on this forum with more foresight...
rinsbag, suggest you put the amp to the side, educate yourself a bit in electronics (i.e. learn to read schematics, discover what each component and its variants look like, acquire some basic service equipment, and do a couple of simple projects FIRST). Then, get back to the amp.
🙂
Cheers!
Clem
ps: Or, send it to Chris - I have no idea how far apart you guys live... hehehe...
rinsbag, suggest you put the amp to the side, educate yourself a bit in electronics (i.e. learn to read schematics, discover what each component and its variants look like, acquire some basic service equipment, and do a couple of simple projects FIRST). Then, get back to the amp.
🙂
Cheers!
Clem
ps: Or, send it to Chris - I have no idea how far apart you guys live... hehehe...
Hi Clem,
You have no idea how close rinsbag is to me. Less than an hour's drive (through some really pretty escarpment country too!). I was going to wait to see where this went before saying anything.
Hey, DIYaudio members are spread evenly across the globe, and that's really cool!
rinsbag,
Hopefully you have some experience and equipment. Let me know if you need my help.
-Chris
You have no idea how close rinsbag is to me. Less than an hour's drive (through some really pretty escarpment country too!). I was going to wait to see where this went before saying anything.
Hey, DIYaudio members are spread evenly across the globe, and that's really cool!
rinsbag,
Hopefully you have some experience and equipment. Let me know if you need my help.
-Chris
OT
Hi Chris,
Sorry for jumping the gun... 🙂
That near? Gee! It takes me more time to drive home from work, though Manila's traffic conditions are notorious... 15km takes 40 minutes when 'light', and may shoot up to 1.5 hours when 'bad'...
Cheers!
Clem
Hi Chris,
Sorry for jumping the gun... 🙂
That near? Gee! It takes me more time to drive home from work, though Manila's traffic conditions are notorious... 15km takes 40 minutes when 'light', and may shoot up to 1.5 hours when 'bad'...
Cheers!
Clem
ADCOM 555
I just wanted to say thanks for the info. I did power it up after I changed the fuses. Hopefully its still ok.
In response to CHRIS who lives in Georgetown. How much do you think to repair this? Do you do repairs yourself? Can you hit me back and let me know if you think its worth fixing? If its too expensive I think I'll try to do it myself once I learn how to. Any suggestions on where I could learn more about electronics? What things inside are called or what you think may be the problem.
I just wanted to say thanks for the info. I did power it up after I changed the fuses. Hopefully its still ok.
In response to CHRIS who lives in Georgetown. How much do you think to repair this? Do you do repairs yourself? Can you hit me back and let me know if you think its worth fixing? If its too expensive I think I'll try to do it myself once I learn how to. Any suggestions on where I could learn more about electronics? What things inside are called or what you think may be the problem.
Hi rinsbag,
One can never say how much a repair is until you actually see. Not a wise person anyway. Yes, I repair them myself. The amp is worth repairing unless really terrible things have happened. It doesn't sound like that's the case.
What I can do is have you drop by and we'll pop the cover. I can explain what I find and try to estimate it for you. You can decide from there. You may learn a few things just by doing this.
PM me, my e-mail is turned on.
-Chris
One can never say how much a repair is until you actually see. Not a wise person anyway. Yes, I repair them myself. The amp is worth repairing unless really terrible things have happened. It doesn't sound like that's the case.
What I can do is have you drop by and we'll pop the cover. I can explain what I find and try to estimate it for you. You can decide from there. You may learn a few things just by doing this.
PM me, my e-mail is turned on.
-Chris
mine is exactly like that. What my amp is doing is not putting out enough power. I do not think it is putting out the 200 watts or anywhere near it. Maybe only putting out 60 watts at best compared to my other equipment. anyone with any ideas? I do not have the money to get it repaired and would like to do it myself.
Ringsbad,
Best thing you could do for yourself and your friend it to take the amp to Anatek(Chris) and get it fixed right the first time that is if he is willing to do the repair. You could not be in better hands with his work.
Best thing you could do for yourself and your friend it to take the amp to Anatek(Chris) and get it fixed right the first time that is if he is willing to do the repair. You could not be in better hands with his work.
you should not play with this monster!!!
There are high voltages (sort of speaking)...well if you take a look around you will see some "high" value fuses that means lethal!!! it is like a car battery, it is low in volts but very high in amperage (fuse) that can shake your wold in a second 😱. The best choice is to leave it to someone else that knows.😉
PS: yes, those big blue things are electrolytic capacitors and also the other small ones. Those big caps when charged can "melt" a tip of a screwdriver (when shorted)!!!
and the thing is in "some amps" do not use "bleeder resistors" to discharge caps faster when is off, so that means it will "keep" the charge for a long time 😱
This is from ADCOM:
WARNING
TheGFA 555 is a very powerful amplifier capable of delivering very large peaks into low
impedances, exceeding 80 amperes per channel. Therefore, be certain to exercise
extreme caution when making connections to and from the amplifier.Always make certain
that the amplifier is disconnected from the AC outlet, and its large filter capacitors
are discharged. Please note that the power supply capacitors can take more than five
minutes to discharge. Failure to observe this precaution may result in damage to the
loudspeakers and/or blowing of the amplifier's DC RAIL FUSES, conditions which are
NOT covered by the warranty.
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