nelsress begins his WOPL 400 project
- Thread starter nelsress
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- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 75,036
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 75,036
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 75,036
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
More nudes for Nav
Lee, I know it's difficult to follow some of the wires but I didn't want to dress them with wire ties yet until I know I'm keeping all that are here at the moment. If you have any questions regarding something you can't make out, just let me know and I'll try to explain what's been done. One thing that concerned me was how far the fuse tips are pushed out (see last photo) on the (+) and (-) fuse holders, it makes me think that I need shorter fuses, yes? Thanks.
Lee, I know it's difficult to follow some of the wires but I didn't want to dress them with wire ties yet until I know I'm keeping all that are here at the moment. If you have any questions regarding something you can't make out, just let me know and I'll try to explain what's been done. One thing that concerned me was how far the fuse tips are pushed out (see last photo) on the (+) and (-) fuse holders, it makes me think that I need shorter fuses, yes? Thanks.
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- Joined
- Jan 14, 2011
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- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
From what I can see nelson, that should work. Only 2 things I would do differently. The two fused power wires from the right board I would run down, over to the caps , then up. You have them paralleling the AC wires on the thermoswitch wires. And the second is the speaker negative wires I would run to the bottom then over and up ....
Nit pickin I know, but the noise floor can really be affected by some small wiring details. For test purposes you are good to go it looks like....
Nit pickin I know, but the noise floor can really be affected by some small wiring details. For test purposes you are good to go it looks like....
Lee is correct Nelson, you are good to test except you seem to have a stray white wire coming out of the bulk cap area. I think this is your ground that eventually will go to the chassis ground lug but cannot be sure from the photo. That should be taped off to prevent shorts.
After you get it tested you can work on the wire dress. The practice is all DC wires running along the bottom of the chassis, all AC wires running along the top of the chassis.
After you get it tested you can work on the wire dress. The practice is all DC wires running along the bottom of the chassis, all AC wires running along the top of the chassis.
Great, thanks Lee. The fused lines I can move easily. The speaker negative wires are the original wires which I may replace, if I have enough of that good wire remaining, I have to check. If not, I'll re-route them. Just so you know, to me it's not picking nits if changes can benefit the amp from a sonic standpoint, I appreciate the input.
Testing, one, two...
So I double and triple checked my work and decided to do a test power up. Following Joe's instructions, less the control board info as I'm doing this without the control board, it went all the way up to 100% voltage without a hitch, no smell, sounds or smoke, so far so good. With the negative lead from my Fluke attached to the negative (black) binding post of the left channel and the positive lead attached to the positive (white) binding post of the left channel when set to V AC, I get 0.000-0.001, same on the right channel. If I go to my millivolt setting I get around 70 but those are DC volts and I'm pretty sure the outputs are AC, correct? If I am correct, I think I'm looking good to proceed with attaching the control board and doing the bias procedure.
I could be wrong (of course!) so I'll hold off on that until I hear from Lee or Joe on that.
I did screw up a little but fortunately I didn't have any issues. I believe Lee told me to do the DC protect circuit prior to testing, now that I think about it, but I didn't install that circuit yet. So, prior to connecting the control board to the backplane boards, I should no doubt install the DC protect circuit. Before I do any of that though, I think I'll re-route the wires the way Lee and Joe recommended and also replace the left and right channel negative output binding posts with the new ones I got with the DC protect circuit, along with the new RCA jacks. I love it when a plan comes together!
So I double and triple checked my work and decided to do a test power up. Following Joe's instructions, less the control board info as I'm doing this without the control board, it went all the way up to 100% voltage without a hitch, no smell, sounds or smoke, so far so good. With the negative lead from my Fluke attached to the negative (black) binding post of the left channel and the positive lead attached to the positive (white) binding post of the left channel when set to V AC, I get 0.000-0.001, same on the right channel. If I go to my millivolt setting I get around 70 but those are DC volts and I'm pretty sure the outputs are AC, correct? If I am correct, I think I'm looking good to proceed with attaching the control board and doing the bias procedure.
I could be wrong (of course!) so I'll hold off on that until I hear from Lee or Joe on that.
I did screw up a little but fortunately I didn't have any issues. I believe Lee told me to do the DC protect circuit prior to testing, now that I think about it, but I didn't install that circuit yet. So, prior to connecting the control board to the backplane boards, I should no doubt install the DC protect circuit. Before I do any of that though, I think I'll re-route the wires the way Lee and Joe recommended and also replace the left and right channel negative output binding posts with the new ones I got with the DC protect circuit, along with the new RCA jacks. I love it when a plan comes together!
So I double and triple checked my work and decided to do a test power up. Following Joe's instructions, less the control board info as I'm doing this without the control board, it went all the way up to 100% voltage without a hitch, no smell, sounds or smoke, so far so good. With the negative lead from my Fluke attached to the negative (black) binding post of the left channel and the positive lead attached to the positive (white) binding post of the left channel when set to V AC, I get 0.000-0.001, same on the right channel. If I go to my millivolt setting I get around 70 but those are DC volts and I'm pretty sure the outputs are AC, correct? If I am correct, I think I'm looking good to proceed with attaching the control board and doing the bias procedure.
I could be wrong (of course!) so I'll hold off on that until I hear from Lee or Joe on that. I did screw up a little but fortunately I didn't have any issues. I believe Lee told me to do the DC protect circuit prior to testing, now that I think about it, but I didn't install that circuit yet. So, prior to connecting the control board to the backplane boards, I should no doubt install the DC protect circuit. Before I do any of that though, I think I'll re-route the wires the way Lee and Joe recommended and also replace the left and right channel negative output binding posts with the new ones I got with the DC protect circuit, along with the new RCA jacks. I love it when a plan comes together!
I could be wrong (of course!) so I'll hold off on that until I hear from Lee or Joe on that.
I did screw up a little but fortunately I didn't have any issues. I believe Lee told me to do the DC protect circuit prior to testing, now that I think about it, but I didn't install that circuit yet. So, prior to connecting the control board to the backplane boards, I should no doubt install the DC protect circuit. Before I do any of that though, I think I'll re-route the wires the way Lee and Joe recommended and also replace the left and right channel negative output binding posts with the new ones I got with the DC protect circuit, along with the new RCA jacks. I love it when a plan comes together!
Thanks Joe,
Well the good news is still no sparks, smoke, etc. but the bad news is that apparently, I've got some issues somewhere as I didn't get the readings I was supposed to get. Here's what I found following the above procedure:
Left Channel
B+ Test point 60mV
B- Test point 183mV
Output Test point 50mV
Right Channel
B+ Test point 60mV
B- Test point 170mV
Output Test point 47mV
The readings are relatively consistent from channel to channel but nowhere near what they're supposed to be. Any suggestions as to where to look to find the problem? Thanks.
Well the good news is still no sparks, smoke, etc. but the bad news is that apparently, I've got some issues somewhere as I didn't get the readings I was supposed to get. Here's what I found following the above procedure:
Left Channel
B+ Test point 60mV
B- Test point 183mV
Output Test point 50mV
Right Channel
B+ Test point 60mV
B- Test point 170mV
Output Test point 47mV
The readings are relatively consistent from channel to channel but nowhere near what they're supposed to be. Any suggestions as to where to look to find the problem? Thanks.
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Hi Joe,
I had it set to volts but was getting such low readings that I switched it to mV to get whole numbers. Okay, bear with me please and keep in mind this is new to me, I've heard you guys talk about rail fuses and rail voltages but I don't know what that means. Are you just referring to the two fuses in the fuse holders next to the AC mains fuse holder that are referred to as "positive supply fuse" and "negative supply fuse" in the owners manual? I put a 3 AGC in each of the (+) and (-) supply fuse holders and an 8 AGC fuse in the AC main fuse holder. I'll go check them to make sure they're still intact and if so, I'll check the "bulk caps", which I assume are the PS replacement caps? When you say I'm supposed to get 80v at the bulk caps, are you again referring to DC? Thanks Joe.
I had it set to volts but was getting such low readings that I switched it to mV to get whole numbers. Okay, bear with me please and keep in mind this is new to me, I've heard you guys talk about rail fuses and rail voltages but I don't know what that means. Are you just referring to the two fuses in the fuse holders next to the AC mains fuse holder that are referred to as "positive supply fuse" and "negative supply fuse" in the owners manual? I put a 3 AGC in each of the (+) and (-) supply fuse holders and an 8 AGC fuse in the AC main fuse holder. I'll go check them to make sure they're still intact and if so, I'll check the "bulk caps", which I assume are the PS replacement caps? When you say I'm supposed to get 80v at the bulk caps, are you again referring to DC? Thanks Joe.
Yes to all of the above Nelson. I see by your pictures that you are using 3AG fuses (1/4" x 1-1/4") in the positive and negative supply fuses (rail fuses). These are supposed to be AGX (1/4" x 1"), very fast blow style fuses. Not a big deal right now but you will want to get the right fuses eventually. I noticed because your tip connections are hanging way out of the fuseholder housing in your picture.
Thanks Joe. Regarding the fuse length yes, I was wondering about that and I think my query regarding it was lost in a bunch of other, more important questions in one of my recent posts, I'll take care of that. When I check the bulk caps, do I put the negative lead from my meter to the chassis ground or to the copper buss ground, somewhere else or is any ground okay? I have yet to see my DMM read minus volts but then most of my experience using it is in commercial and residential electrical work.