Posted: Mon Jun 29, 2009 18:04 Post subject: WRT54G bad power regulation
So I have a WRT54G that makes doesn't work, and the fairly loud buzz/hum that comes from the board indicates to me that it has a problem somewhere in power regulation.
I've looked on eBay, and these things aren't worth a ton of money anymore, so I don't want to have to go through herculean efforts to save it. I do know that all the power regulation really does is provide the board with a very stable 3.3 volts.
Would it be possible for me to just find some other stable 3.3 volt supply, and solder it in directly to the output of the onboard power regulation, effectively bypassing the bad onboard regulation? Does anybody know where the actual final output of the onboard regulation is (it's hard for me to test, given that I don't have a working model available)?
It's not the end of the world if I end up completely frying the thing, but it would be awesome if I could find a cheap way to save it.
Joined: 04 Jan 2007 Posts: 11564 Location: Wherever the wind blows- North America
Posted: Mon Jun 29, 2009 18:12 Post subject: Re: WRT54G bad power regulation
Amall wrote:
So I have a WRT54G that makes doesn't work, and the fairly loud buzz/hum that comes from the board indicates to me that it has a problem somewhere in power regulation.
I've looked on eBay, and these things aren't worth a ton of money anymore, so I don't want to have to go through herculean efforts to save it. I do know that all the power regulation really does is provide the board with a very stable 3.3 volts.
Would it be possible for me to just find some other stable 3.3 volt supply, and solder it in directly to the output of the onboard power regulation, effectively bypassing the bad onboard regulation? Does anybody know where the actual final output of the onboard regulation is (it's hard for me to test, given that I don't have a working model available)?
It's not the end of the world if I end up completely frying the thing, but it would be awesome if I could find a cheap way to save it.
Thanks!
Here is another option for you....and I use this when I need to...it works very well. Take an old PC power supply. They supply a variety of voltages, but the most useful are the +12 and +5 that normally supply power the the HDD and various other periferals. These powers are typically in the 30-35Amp range for the +5V and in the 8-10Amp range for the 12V...which is more then enough for any router out there.
I have cut the power pack cord off the old router pack and soldered it directly to the appropriate wire pair from the PC supply....the only thing you have to remember is to jumper out the power supply enable wire....do a google search for PC power supply pinouts and you will find the enable wire...just short it to ground and the power supply will work when it is plugged in.
And....it is regulated....for those reading this that have buffalo units running on +3.3V....there is also a +3.3V line on the PC power supply also. (but I don't know the typical amperage off the top of my head)
redhawk _________________ The only stupid question....is the unasked one.
Thanks for the tip, I think I have some old pc power supplies lying around somewhere...
The thing is, my existing 12v power supply works fine (and I've tried the 12v power supply from a different WRT54g to confirm). The problem is on the router's board. So, simply cutting the cord and wiring in my new power source won't exactly fix it.
I've heard that all the onboard power regulation does is decrease the voltage to 3.3v and stabilize it (further than the stabilization in the wall wart). I can use an old PSU for my stable 3.3 volts, but I will need to solder it in directly on the router board where the onboard power regulation outputs are. Do you know where that would be? I can post pictures of my board if that would help.
Joined: 04 Jan 2007 Posts: 11564 Location: Wherever the wind blows- North America
Posted: Tue Jun 30, 2009 0:43 Post subject:
Amall wrote:
Thanks for the tip, I think I have some old pc power supplies lying around somewhere...
The thing is, my existing 12v power supply works fine (and I've tried the 12v power supply from a different WRT54g to confirm). The problem is on the router's board. So, simply cutting the cord and wiring in my new power source won't exactly fix it.
I've heard that all the onboard power regulation does is decrease the voltage to 3.3v and stabilize it (further than the stabilization in the wall wart). I can use an old PSU for my stable 3.3 volts, but I will need to solder it in directly on the router board where the onboard power regulation outputs are. Do you know where that would be? I can post pictures of my board if that would help.
Not right off hand....3.3V may not be the only voltage used on these older 54G units either. They may use the +5V for some chip power...so you might have to solder in dual supplies to make things work.
I've never really probed that thoroughly on a 54G unit to tell you what reduced voltages go where.
redhawk. _________________ The only stupid question....is the unasked one.
I checked all the caps pretty thoroughly, and they all looked good and unexploded. However, if I could get replacements for free or cheap I might try that, thanks!