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pedals 4 pv
Platinum Member
Canada
1351 Posts |
 Posted - 01/03/2008 : 11:38:01
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I developed a hum in my CE-2 I thought it was done. I swapped in my CH-1 and it hummed too! Turns out my ACA-120g adaptor is the cause. This is much better than a broken CE-2 or CH-1. Is there any repair for this or is it screwed? There must be a capacitor or diode gone bad inside of it. I'll just get a PSA-120, but I would like to try to fix the ACA-120g as they have a better, more flexible lead wire, and I would appreciate any tips from any one who has repaired one. |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 01/03/2008 : 13:19:14
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Hi pedals 4 pv
We don't have any 120VAC adapters out here in Oz. (all 240VAC here)
But if you can get it apart, take a pic or two of the insides.
As far as I can tell, it will be just 4 didoes in a bridge, or an actual 4 legged bridge rectifier, & a capacitor.
As the older ACA pedals are not regulated.
Maybe the Cap. has dried out, or one of the diodes in the bridge has gone south.
Easy fix, if you can get it open.
Good luck Dr. Bob 
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pedals 4 pv
Platinum Member
Canada
1351 Posts |
Posted - 01/04/2008 : 03:03:26
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| I got it open without destroying it, and the four diodes test good. It has a 1000uf radial electrolytic capacitor rated 16v. I am going to get a new cap, the closest that I can find is rated 25v but I don't think that matters, or does it? |
Edited by - pedals 4 pv on 01/04/2008 03:23:27 |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 01/04/2008 : 04:17:21
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quote:
Originally posted by pedals 4 pv
I got it open without destroying it, and the four diodes test good. It has a 1000uf radial electrolytic capacitor rated 16v. I am going to get a new cap, the closest that I can find is rated 25v but I don't think that matters, or does it?
Hi pd4PV
As long as the cap fits mechanically, higher voltages are ok.
And modern caps end to be physically smaller anyway.
The electrolyte in the capacitor has probably dried out.. A common problem with plug packs, they tend to be sealed units & the insides always run at elevated temperatures, helping to speed up, drying out the insides of the cap.
You might even want to try using a 2200uf (mfd) cap if it will fit, this will reduce the residual ripple & hum even more.
from your other post.
Yes the 240VAC outlets & plugs are different in Australia.
I will see if I can find a pic.
And different to Europe & England as well.
Regards & good luck with the cap change... Dr. Bob |
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pedals 4 pv
Platinum Member
Canada
1351 Posts |
Posted - 01/09/2008 : 00:56:45
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| Well I changed the cap but to no avail. I guess its done |
Edited by - pedals 4 pv on 01/09/2008 00:57:06 |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 01/09/2008 : 08:03:41
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quote:
Originally posted by pedals 4 pv
Well I changed the cap but to no avail. I guess its done
Hi pedals 4 pv[
By no avail... do you mean it still hums, or it's dead?
What cap did you use?
can you take some measurements with your DVM-multimeter for me.
If it's just hum? how bad is the hum?
it might be a diode breaking down under load?
Basically, give me some more info...
Better still take some pics, you can PM them to me.
Regards Dr.
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pedals 4 pv
Platinum Member
Canada
1351 Posts |
Posted - 01/09/2008 : 09:26:02
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| I installed a new 1000uf 25v cap and there was no change at all, it still makes both of my choruses (chori?) hum when engaged. It works fine on other pedals so I think you are right Dr. Bob, its probably diodes. The electronics shop is quite a way from here so I'll try to get some next time I am in the neighbourhood. I wanted to pick up a 2.1 X 5mm jack and a battery clip to eliminate the battery from my KM-2 mixing amplifier so that gave me another reason to go there. I just attached the jack to the clip and the wires have room to poke through the space where the two parts of the casing meet, so I didn't alter the KM-2 in any way. |
Edited by - pedals 4 pv on 01/09/2008 09:27:28 |
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starr36
Platinum Member
Canada
1172 Posts |
Posted - 01/25/2008 : 07:44:35
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I got 4 nib aca's unused.
Post me back if you want to buy one.
Although it can be fun to fix any broken piece of electronics, no doubt, an adapter is more cost effective to replace if you count your time.
Sometimes you get lucky; sometimes you don't.
Lucky for me: Digitech Whammy II, kept forgetting where it was when pitching the note. Undo 4 screws, move LED motion sensor pickup closer to the LED travel path. Put back 4 screws. The II never forgot where it was again, and played locked on homage to Tom Morello.
Lucky 2 for me: DC-3 only produced single sine wave that made you seasick. Undo 4 screws, resolder the depth control. Put back 4 screws. The DC-3 chorused away just like Glass Tiger did in the 80's.
Lucky 3 for me: DS-1 SS MIJ $10.00, produced no sound. Undo four screws, examine circuit board and discover broken trace. Solder teeny patch wire. Put Back 4 screws. Glorious DS-1 shredding to celebrate New Year's Eve Dec 31, 1979 in Times Square.
Unlucky for me: DD-2 that repeated forever. Undo four screws, Resolder Feedback control, order schematic diagram, buzz out components and check them all, 6 hours later, DD-2 is in a box all taken apart. 2 years later, DD-2 still in box all taken apart. I have a broken $300.00 DD-2. It's pretty cool all taken apart - some pretty wire in it too. |
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pedals 4 pv
Platinum Member
Canada
1351 Posts |
Posted - 01/25/2008 : 08:00:21
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I bought a PSA-120S, and as it is 500ma, it took the place of 2 wall warts so now I have a spare. I thought that I would give the repair a try but I am not going to waste too much time on it.
Looks like your three times lucky anyway starr36. 10 dollar MIJ DS-1 ain't too bad. |
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Anyone repaired an ACA-120g?
