I doubt the socket it self is ruined. You would probably see damage to it if it were. Your fuse isn't blown, I know pretty obvious thing to check. I would take a bunch of more pictures of everything now that you have redone it. I really doubt the switch is shot it may just be how it it is wired. Are you switching both the hot and neutral on your switch? Something about your switch wiring looks really wrong but it could be just to early for me in the morning. It may help. I would take a bunch of more pictures of everything now that you have redone it. Good luck.
Is this how you have wired your transformer? Yeah yeah I am no artist. If you are switching both your hot and neutral you should have it wired like the above photo. Obviously there is a ground too but I didn't draw that in.
Is this how you have wired your transformer? Yeah yeah I am no artist. If you are switching both your hot and neutral you should have it wired like the above photo. Obviously there is a ground too but I didn't draw that in.
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Make sure that the fuse is on the hot line side and not the nuetral.
You should be able to check the IEC by measureing continuity between the input and output pins for each connector. Also make sure no continuity between pins.
From your pictures it looks as if you tie both the nuetral and the ground together at the switch. large green wire. If so that is not a good idea. The ground is a safety ground and should not be in the power path. The ground should be tied to the center of your amp's star ground. Take a look at George's site on wiring diagrams, particularly on grounded.
In the US nuetral is(should be) at ground potential (often tied together in the house circuit breaker box). You must consider them as seperate. The nuetral is designed to carry the operating current and the ground is only a drain in the event of a short or failure.
If the green wire isn't ground, then sorry for the ramble.
You should be able to check the IEC by measureing continuity between the input and output pins for each connector. Also make sure no continuity between pins.
From your pictures it looks as if you tie both the nuetral and the ground together at the switch. large green wire. If so that is not a good idea. The ground is a safety ground and should not be in the power path. The ground should be tied to the center of your amp's star ground. Take a look at George's site on wiring diagrams, particularly on grounded.
In the US nuetral is(should be) at ground potential (often tied together in the house circuit breaker box). You must consider them as seperate. The nuetral is designed to carry the operating current and the ground is only a drain in the event of a short or failure.
If the green wire isn't ground, then sorry for the ramble.
I appreciate the clarification. I live on a military base in Tokyo and we have our own power system on base. It makes things a little confusing/troubling because outside the gates Japan runs on 100V/50Hz but inside we run at 120V but still 50Hz (which makes everyone's clocks run a little off!). To make matters worse, I will be moving to Germany in a couple of months so I'll have an entire new power system to deal with. That's why I try to buy everything with universal transformers but it does make things a little confusing.
Anyway, on my particular Edcor, good eye bye the way, (the XPWR059) Black/Green and Black (white)/Green (white) equals 120V operation.
As for measuring the IEC, remember this is a thread for dummies
Can you help me out a little on how I would measure continuity and what exactly I'd be looking for?
Oh, one more thing, per an earlier rec, I beefed up the power wire's to 12 gauge and I'm wondering if ground wire should also be that heavy. The ground wire I ran off the RCA's and binding posts is only 20 gauge.
Anyway, on my particular Edcor, good eye bye the way, (the XPWR059) Black/Green and Black (white)/Green (white) equals 120V operation.
As for measuring the IEC, remember this is a thread for dummies
Can you help me out a little on how I would measure continuity and what exactly I'd be looking for?Oh, one more thing, per an earlier rec, I beefed up the power wire's to 12 gauge and I'm wondering if ground wire should also be that heavy. The ground wire I ran off the RCA's and binding posts is only 20 gauge.
As for measuring the IEC, remember this is a thread for dummies
Oh, one more thing, per an earlier rec, I beefed up the power wire's to 12 gauge and I'm wondering if ground wire should also be that heavy. The ground wire I ran off the RCA's and binding posts is only 20 gauge.
12 gauge? Good grief. You're not trying to jump start a car here...
Plug your power cord into the IEC connector, but don't plug the other end into the wall. Make sure you have a good fuse in the fuse holder. Turn the power switch on. Again, the power cord is not plugged into the wall. Set your meter to measure ohms, or set it to check continuity. Put the probes on the free end of the power cord. You should have continuity (or very low ohms) all the way through the cord:IEC:fuse:switch
T:IEC:cord. Make sense?I don't know anything about your switch, but switches are simple binary devices. Have a diagram of a (the) switch in front of you, then follow simple logic. If you haven't much experience and a double pole switch adds confusion, then get a single pole, single throw switch (SPST). That just means two terminals. On/off is usually indicated somewhere on the switch, but it's easy just to test. On means 0R between the poles, Off means infinite R.
One common problem when making final assembly is pinching a wire between the chassis and transformer. Check those.
Final point: The AT7 grid, shorted to ground, may not have anything to do with your problem, but NEVER start the amp unless ALL your static resistances check out. Have the amp schematic in front of you and measure EVERY point to every other point, and every point to ground, and make sure that the resistance reading makes sense. If you are stumped, keep looking at your schematic and measuring (write all measurements on a copy of the schematic) until you understand all the connections. There aren't that many on a tube amp, so do them all. If you do this you will know your amp well.
Sheldon
One common problem when making final assembly is pinching a wire between the chassis and transformer. Check those.
Final point: The AT7 grid, shorted to ground, may not have anything to do with your problem, but NEVER start the amp unless ALL your static resistances check out. Have the amp schematic in front of you and measure EVERY point to every other point, and every point to ground, and make sure that the resistance reading makes sense. If you are stumped, keep looking at your schematic and measuring (write all measurements on a copy of the schematic) until you understand all the connections. There aren't that many on a tube amp, so do them all. If you do this you will know your amp well.
Sheldon
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Setup your meter for measuring volts AC. If it is not auto-ranging, be sure to select a high enough range. Connect it across the hot and neutral terminals and then plug in the cord. If you don't see anything, then you know either the cord or the socket is bad. Just make sure you hook up the meter before applying power.
Did you ever sort this out? I'm thinking you might have inadvertently swapped your connections to the tip & ring of the RCA input jack. It shouldn't cause any harm to anything, but when you get the amp going that channel won't make any sound.
I really appreciate everyone taking the time to chime in here. My wife is pretty shocked that are people willing to look at the crazy pictures I've posted and help me trace down the issue; she can be a little cynical .
Anyway, with all the suggestions on the power side I'm sure I'll be able to track down that issue today. It's Sunday here and I have to go to Church, but when I get back I'll run through everything.
I still need to do some more checking on the AT7 issue. I was hoping it was something dumb/easy like mixed up wires but they look right; outermost wires on the quick connectors should go to the pin of the RCA's, innermost wires to the rings?
I also pulled the board out and looked for solder blobs or stray wires on the other side but everything is clean, shiny, and in place. Hmm...
.Anyway, with all the suggestions on the power side I'm sure I'll be able to track down that issue today. It's Sunday here and I have to go to Church, but when I get back I'll run through everything.
I still need to do some more checking on the AT7 issue. I was hoping it was something dumb/easy like mixed up wires but they look right; outermost wires on the quick connectors should go to the pin of the RCA's, innermost wires to the rings?
I also pulled the board out and looked for solder blobs or stray wires on the other side but everything is clean, shiny, and in place. Hmm...
Alright, I spent several very frustrating hours today rewiring, checking, switching, rewiring, checking, etc and I'm still stumped. I've checked the IEC socket and it appears to be fine (clipped the meter on the hot and cold side and plugged it into the wall and got 114V between the tabs on the socket). I replaced the switch (this one is only 3A 125V but I would think it would still be OK). I then plugged into the wall and got 114V on the tab at the socket and the tab on the switch but with the switch in the "on" position I'm not getting any voltage on the other side of the switch that goes to the transformer. When I switch the switch to "off" it blows the fuse. I have the switch grounded to the star ground this time.
Also, with the AT7 issue, I re-soldered the resistors on the board and re-soldered the the wires going to the RCA sockets (I hate soldering RCA's!). I still get no reading on the one side with everything wired up but if I undo either of the wires on the quick connect terminals on the problem side of the AT7 I get the appropriate 220K reading. Once those wires are wired back into the quick connects, back to 0. Every other resistance on the board checks out according to the wonderful guide Ty posted earlier (with everything wired up).
So, any other thoughts? Here are some new pics that might help with the diagnosis.
Picasa Web Albums - jeremyrobertson1 - Simple SE v2
The frustrating thing about this is that everything fired up first shot on the breadboard and played music immediately; I was actually pretty lucky because I had no idea how to test the thing and it just happened to work. Now that I've got everything into the chassis I've got these two problems. I'm assuming it must be a ground issue somewhere. Do you think the two are related?
Also, with the AT7 issue, I re-soldered the resistors on the board and re-soldered the the wires going to the RCA sockets (I hate soldering RCA's!). I still get no reading on the one side with everything wired up but if I undo either of the wires on the quick connect terminals on the problem side of the AT7 I get the appropriate 220K reading. Once those wires are wired back into the quick connects, back to 0. Every other resistance on the board checks out according to the wonderful guide Ty posted earlier (with everything wired up).
So, any other thoughts? Here are some new pics that might help with the diagnosis.
Picasa Web Albums - jeremyrobertson1 - Simple SE v2
The frustrating thing about this is that everything fired up first shot on the breadboard and played music immediately; I was actually pretty lucky because I had no idea how to test the thing and it just happened to work. Now that I've got everything into the chassis I've got these two problems. I'm assuming it must be a ground issue somewhere. Do you think the two are related?
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You've got a blob of solder that found its way down into your RCA jack, and it is shorting tip to ring. You will most likely have to replace that RCA jack.
That sounds odd. There must be some wiring mistake at the switch. Are you confident you understand which terminals on the switch are the poles, and which are the throws?
Your power transformer appears to have dual primaries for either 120V or 240V operation. I assume you know which wires need to paralleled? I'm guessing the striped green and striped black go together, and the solid green and solid black go together? What is the part number of your PT? Judging by the colors, is it an Edcor? Ah, I see it is the XPWR059. That verifies you have the colors correctly wired.
Blowing fuses suggests that something is shorted to ground where it shouldn't be. Before you disassemble everything again, set your meter to check for continuity. Unplug the amp from the wall. Clip one lead of the meter to the ground point of your amp. Use the other to probe the amp in the following places:
The hot & neutral tabs of the IEC receptacle
Both tabs on the fuse holder
All four tabs on the DPST power switch
None of these should indicate continuity, regardless of whether the power switch is open or closed. If any of these points are shorted, don't go any further until you figure out why.
On the secondary side of the power transformer, you should also check for shorts. Just keep everything wired up exactly as you have it now - don't disconnect anything. Do be sure the amp is not plugged into the wall. Check these points by touching the probe to the screw terminal of the Phoenix connector on the circuit board:
The 6.3V winding (yellow wires on the Edcor)
The 5.0V winding (brown wires on the Edcor)
The filter inductor (choke)
Some of these guys might elicit a short chirp from your meter, depending on its sensitivity. This is OK - you've just touched a point which is tied to ground through a capacitor. The beep should quickly fade as the cap charges to the sense voltage of your meter (maybe a 9V battery at most).
You should also set your meter to check ohms, and verify the readings of the HT secondary coming from the power transformer. Again, the amp is not plugged into the wall for this check. Measure at each of the two red wires on the circuit board (right next to the brown 5.0V wiring). You will likely see something between 10 and 100 ohms. My Hammond 374BX measures about 40 ohms per leg.
Check these things, and let us know what you see.
One thing that can happen with switches is if you heat the terminals up too much with the iron, they shift/sink into the plastic and the internal contact can no longer make a connection. I always check the continuity of the switch contacts in the open and closed position, just to make sure they are not arranged in some unusual way.
At this point my confidence in just about everything is rapidly disappearing!
Anyway, the switch came from the Japanese store so I can't read much of the package but I can read that "1 and 4", the top tabs, correspond to "on" in the picture and that "3 and 6", the bottom tabs, correspond to "off" in the picture. I I assume I've got it right; black and read (with fuse) come from the IEC to the top two tabs and the "two" wires from the PT attach to the bottom two tabs.
I did the check for continuity on all the points indicated and got readings of infinity at all of them (or 1 on my digital meter). I also checked the choke, 6.3V, and 5V phoenix connectors and got readings of infinity for all. I'm assuming that means no shorts; right? Continuity, or a reading of 1.2ish on my meter indicates a short or at least that the circuit is closed at that point; correct? I also checked both the HV points (the two red wires next to the two brown wires) and got 55 ohms for each so I'm assuming that's good.
While I was at it I checked the phoenix connectors at the inputs and both purple/white wires showed continuity (as I assume they should since they are ground wires) and the red/white wire on the problem side read the same as well. So, I'm guessing the diagnosis of a wrecked RCA is probably correct. There is definitely solder in the "tube" of the RCA and it sounds like that is a no-no. So, back to the Japanese store to find new RCA's.
So it appears the question of the grid resistor has been solved; now its just the power issue.
As an aside, I REALLY appreciate the step by step walk through. This is very much a learning project for me (I've never touched a soldering iron before) and I definitely have learned a lot, especially the basics of using a multimeter! I decided that since everyone keeps talking about continuity I ought to at least look that up and see what you're talking about and right off, learned something new.
Anyway, you guys are life savers and if it kills me (which hopefully it won't
) I will get this thing working! I've already got the next couple of projects lined up, so I can't give up now; I've already got a big stack of parts on the table that drives my wife crazy! A priority for the new house in Berlin is a hobby room for dad; our house in Tokyo just isn't that big...P.S. I checked my old switch and it looks like one said shows an infinity whether the switch is on or off and the other side shows continuity whether the switch is on or off; I'm assuming that means that switch is toast, correct? It's unfortunate because that's the big/beefy/expensive one!
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It sounds like you need to use your continuity checker to figure out that switch. You have it wired like a DPST switch (double-pole, single throw: Switch - Wikipedia, the free encyclopedia). If it blows the fuse in the off position, clearly something isn't right.
With the switch in the off position, both poles should measure infinite resistance (no continuity). With the switch in the on position, they should measure near zero. If they don't, try measuring between different pairs of terminals to figure out which terminal goes to which pole. I'm going to guess and say that what you actually have is a SPDT switch. If so, you can still use it to only switch the hot side (between the fuse and the transformer). Just connect the other side of the power transformer right to the neutral.
With the switch in the off position, both poles should measure infinite resistance (no continuity). With the switch in the on position, they should measure near zero. If they don't, try measuring between different pairs of terminals to figure out which terminal goes to which pole. I'm going to guess and say that what you actually have is a SPDT switch. If so, you can still use it to only switch the hot side (between the fuse and the transformer). Just connect the other side of the power transformer right to the neutral.
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Stupid switches...
OK, I checked the continuity on the switch. Checking between the two "top" tabs (these are the two tabs that are on the "on" position of the switch) they are always showing continuity between them whether the switch is off or on. Checking between the two "bottom" tabs (the ones on the "off" side of the switch and currently wired to my red and black wires in my pictures) I get continuity when the switch is off but when I switch it to on that connection breaks. Measuring between the either "side" of the switch (red to the transformer wire or black to the transformer wire) gives no continuity regardless of if the switch is on or off.
I was a little worried after you mentioned that excess heat with the iron can ruin switches (I have been to known to have a heavy hand with the heat) but it doesn't seem like I've ruined it, does it?
Also, I checked continuity on both tabs of the fuse holder and I did get continuity between them (with a new fuse) which I'm assuming is what I want.
Anyway, I think you're probably right in that this switch is not a DPST but a SPDT. Am I right?
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