I've looked at these for awhile now and it doesn't seem to me they match, exactly, as far telling what is wired where.
I need to replace the filter cap and can't figure out which wire goes where.
It's very doughtful I'll be able to find an exact cap so I need to know how to wire it up to get the correct voltages to the correct places.
[IMG:798:531]http://i46.photobucket.com/albums/f136/ ... Layout.jpg[/img]
[IMG:575:800]http://i46.photobucket.com/albums/f136/ ... onSche.jpg[/img]
Schematic vs Layout ?
Moderators: pompeiisneaks, Colossal
Re: Schematic vs Layout ?
The thing is, the can cap is really 3 caps (40uf-20uf-20uf/450v). If you look at the schematic, you will see the 4.7K and 10K resistors in the power supply ladder. These are on the layout, attached to the can cap terminals, lower left.
It is easier to replace these resistors than to save them. Probably, you would toast them in trying to desolder them anyway and they are worth maybe 10 cents each. Take one or more good quality digital pictures before you do anything, so you have a reliable reference. Memory is never a reliable reference. Then clip the wires as close as you can, and hope they are still serviceable for the new can cap. if not you might need to run new wire.
While you are working, best practice is to do all of them. There is also a 10uf/450v cap on the other side of the choke and consider the 10uf/100v in the bias supply.
I feel compelled to ask, are you sure you are up to this? The inside of an amp is potentially lethal, even long after it is unplugged from the a/c power supply. Your question prompts this cautionary warning, as it suggests your knowledge level isn't where it needs to be. If I'm wrong about that (maybe you work on other stuff, not guitar amps), please excuse me for erring on the side of caution.
By way of contrast, I am an amateur, not a tech. I've never looked at this particular set of drawings before, and I found the answer very quickly. It gives me the feeling you lack the necessary familiarity. It is far cheaper to take this to a tech than to risk it all to save just a few dollars. A good tech will be in and out on this job in less than an hour. Send the work out, my friend, and live to tell the tale.
It is easier to replace these resistors than to save them. Probably, you would toast them in trying to desolder them anyway and they are worth maybe 10 cents each. Take one or more good quality digital pictures before you do anything, so you have a reliable reference. Memory is never a reliable reference. Then clip the wires as close as you can, and hope they are still serviceable for the new can cap. if not you might need to run new wire.
While you are working, best practice is to do all of them. There is also a 10uf/450v cap on the other side of the choke and consider the 10uf/100v in the bias supply.
I feel compelled to ask, are you sure you are up to this? The inside of an amp is potentially lethal, even long after it is unplugged from the a/c power supply. Your question prompts this cautionary warning, as it suggests your knowledge level isn't where it needs to be. If I'm wrong about that (maybe you work on other stuff, not guitar amps), please excuse me for erring on the side of caution.
By way of contrast, I am an amateur, not a tech. I've never looked at this particular set of drawings before, and I found the answer very quickly. It gives me the feeling you lack the necessary familiarity. It is far cheaper to take this to a tech than to risk it all to save just a few dollars. A good tech will be in and out on this job in less than an hour. Send the work out, my friend, and live to tell the tale.
Re: Schematic vs Layout ?
I did take some pics and a slow panned video of the guts.Phil_S wrote:The thing is, the can cap is really 3 caps (40uf-20uf-20uf/450v). If you look at the schematic, you will see the 4.7K and 10K resistors in the power supply ladder. These are on the layout, attached to the can cap terminals, lower left.
It is easier to replace these resistors than to save them. Probably, you would toast them in trying to desolder them anyway and they are worth maybe 10 cents each. Take one or more good quality digital pictures before you do anything, so you have a reliable reference. Memory is never a reliable reference. Then clip the wires as close as you can, and hope they are still serviceable for the new can cap. if not you might need to run new wire.
While you are working, best practice is to do all of them. There is also a 10uf/450v cap on the other side of the choke and consider the 10uf/100v in the bias supply.
I feel compelled to ask, are you sure you are up to this? The inside of an amp is potentially lethal, even long after it is unplugged from the a/c power supply. Your question prompts this cautionary warning, as it suggests your knowledge level isn't where it needs to be. If I'm wrong about that (maybe you work on other stuff, not guitar amps), please excuse me for erring on the side of caution.
By way of contrast, I am an amateur, not a tech. I've never looked at this particular set of drawings before, and I found the answer very quickly. It gives me the feeling you lack the necessary familiarity. It is far cheaper to take this to a tech than to risk it all to save just a few dollars. A good tech will be in and out on this job in less than an hour. Send the work out, my friend, and live to tell the tale.
I've replaced smaller value caps in a couple amps, just traded one value for another, but nothing like a filter cap.
Done a bunch of soldering, but not on anything that could kill me
I have a guy that can do the job so I'll prolly give him a call.
Thanks man...
Yes, I'm new here..