- Joined
- Jul 6, 2010
- Messages
- 17,704
- Tagline
- Broken beyond repair but highly affable
Resurrected a Customized WOPL 400
- Thread starter scottonnob
- Start date
- Joined
- Jun 11, 2010
- Messages
- 6,850
- Location
- Powhatan, Virginia, United States
- Tagline
- WassupYa Mang?
Ok, please confirm that your caps are oriented correctly - from the bottom of the chassis it should go like this.. (think of two batteries in a flashlight)
(neg term) (pos term)---BUSS BAR--(neg term) (pos term)
And then...
(neg term) (pos term)---BUSS BAR--(neg term) (pos term)
And then...
- NEG Term should be connected to the bridge, negative terminal and the far POS term to the positive terminal (the one terminal that is different in orientation)
- NEG Term should also be connected to both one side of the negative fuse holder and the UNFUSED negative connection on the left backplane
- POS Term should also be connected to both one side of the positive fuse holder and the unfused positive connection on the left backplane
- The OTHER sides of the fuse holders should be connected to the FUSED terminals, same polarity as what is feeding each fuse.
- Joined
- Jun 11, 2010
- Messages
- 6,850
- Location
- Powhatan, Virginia, United States
- Tagline
- WassupYa Mang?
Ok.. so follow what I posted.. done enough 400's to do them blindfolded at this point. 
Reorient the caps if you need to, and start from the list above. No wires other than what is specified (for now.. obviously if you are doing a DC protect you'll need to have one extra unfused positive wire reaching over to the right side, near the speaker outputs).
Reorient the caps if you need to, and start from the list above. No wires other than what is specified (for now.. obviously if you are doing a DC protect you'll need to have one extra unfused positive wire reaching over to the right side, near the speaker outputs).
- Joined
- Apr 28, 2015
- Messages
- 251
- Tagline
- ---
Okay, I checked the caps for orientation and, unless I'm really a dim bulb, which is quite possible, they seem to be correct. I photographed the caps close-up, and I think you can see the polarity symbols on the boards. But, as can be seen, the two outside posts have only the rectifier wire on them. Additionally, I'm hampered by the fact that the boards shown in the instructions I received with my kit are quite different from the boards that I received.
- Joined
- Jun 11, 2010
- Messages
- 6,850
- Location
- Powhatan, Virginia, United States
- Tagline
- WassupYa Mang?
Ok, think of it this way..
1. You have two sets of positive and negative supply wires to connect, one fused and the other unfused. The unfused connections terminate at the very bottom of the left channel backplane board.
2. The transformer supplies the initial AC voltage to the diode bridge, and through the two terminals on the bridge that are not marked by either + or - (typically ~ indicating AC)
3. The other two terminals on the bridge are the DC outputs, which powers the rest of the amp. One terminal on the bridge is of a different orientation, which makes it the positive output of the bridge. The other is the negative output.
4. The same two DC output terminals should feed the positive (the upper terminal) and the negative (lower terminal) of the caps , again. from the bottom we have the negative connection on the lower cap, the copper bar between the lower cap's positive terminal and the upper cap's negative terminal, and finally the positive terminal at the top (which is where the positive output from the bridge should go)
With me so far?
Now.. how do we go about connecting essentially what is the power supply of the amp to the rest of the amp, with terminals on the backplanes for UF +, UF - (these are the two at the very bottom), and at the same time "fuse" the other two terminals on the backplane (fused +, fused -)?
1. We first need connections from the UNFUSED cap terminals (the very bottom of the lower cap and the very top of the upper cap), feeding the two fuseholders.
2. We also need connections again from the same two unfused cap terminals, feeding the two unfused pos/neg terminals at the bottom of the left backplane.
3. And.. now that we made connections from the power supply to the two fuse holders, we need to bring the now FUSED power from the other sides of both fuse holders back down to the left backplane's main FUSED positive and negative terminals.
1. You have two sets of positive and negative supply wires to connect, one fused and the other unfused. The unfused connections terminate at the very bottom of the left channel backplane board.
2. The transformer supplies the initial AC voltage to the diode bridge, and through the two terminals on the bridge that are not marked by either + or - (typically ~ indicating AC)
3. The other two terminals on the bridge are the DC outputs, which powers the rest of the amp. One terminal on the bridge is of a different orientation, which makes it the positive output of the bridge. The other is the negative output.
4. The same two DC output terminals should feed the positive (the upper terminal) and the negative (lower terminal) of the caps , again. from the bottom we have the negative connection on the lower cap, the copper bar between the lower cap's positive terminal and the upper cap's negative terminal, and finally the positive terminal at the top (which is where the positive output from the bridge should go)
With me so far?
Now.. how do we go about connecting essentially what is the power supply of the amp to the rest of the amp, with terminals on the backplanes for UF +, UF - (these are the two at the very bottom), and at the same time "fuse" the other two terminals on the backplane (fused +, fused -)?
1. We first need connections from the UNFUSED cap terminals (the very bottom of the lower cap and the very top of the upper cap), feeding the two fuseholders.
2. We also need connections again from the same two unfused cap terminals, feeding the two unfused pos/neg terminals at the bottom of the left backplane.
3. And.. now that we made connections from the power supply to the two fuse holders, we need to bring the now FUSED power from the other sides of both fuse holders back down to the left backplane's main FUSED positive and negative terminals.
- Joined
- Apr 28, 2015
- Messages
- 251
- Tagline
- ---
- Joined
- Apr 28, 2015
- Messages
- 251
- Tagline
- ---
Yeah, I get exactly what you're saying, I just don't understand how I missed that. I don't even know where my copy of the assembly instructions might be. But I'd love to figure out how I missed that. One problem is, I started this project a year ago. Then, here in Northern California, we had three fires, a terrible flood (I live on a big lake), and a family member died. Therefore, I had to put everything away, until now. So I'm still getting back up to speed. I just wish I could see a photo of properly assembled and installed boards. But everything from White Oak is of an older version, and there seems to be big differences.
- Joined
- Apr 28, 2015
- Messages
- 251
- Tagline
- ---
Okay, this is it for the night. And I apologize for taking up your time, but know that it is greatly appreciated. Therefore, I'm going to bug you guys once more. After all, this isn't the time to act with uncertainty, and some of this is counter-intuitive, or I've not understood how to wire this. I just used some wire scraps to mock this up. Red wires run from from the cap to: 1.) Unfused B+ on the board with the green wires from the fuse holder, one green wire to the left board and one to the right board. 2.) From the cap over to the same fuse holder. The blue wires run 1.) From the cap, top lug, to the fuse holder with the other blue wires. 2.) From the cap to Unfused B- on the board. So four additional wires. Also, it wasn't clear whether or not the caps matter, in terms of which to which side. The top cap has the + lug on the top. The bottom cap has - lug on the bottom. I'm guessing those should correspond to B- on the board, to the - cap lug, and B+ on the board to plus cap lug — the opposite of how I mocked it up? Also, I'm not clear about which side of the fuse holder the cap wires need to go to. I assume the wires to the cap go on the top of the fuse holder and the wires to the board on the bottom — the fused side.
And thanks Joe. I just got the documentation, but is this even covered on one of the pages? I couldn't find it. Was it in the doc with the caps I bought from you?
And thanks Joe. I just got the documentation, but is this even covered on one of the pages? I couldn't find it. Was it in the doc with the caps I bought from you?
- Joined
- Apr 28, 2015
- Messages
- 251
- Tagline
- ---
Okay. No sparks, pops, smoke, or sizzles. The dbt never came on and I ended up with a uniform 73 volts across all test points. But my Variac, for whatever reason, is calibrated in percentage of maximum volts, which is 140. I figured 90% was enough to make certain there were no shorts. On to the next step.
- Joined
- Jan 14, 2011
- Messages
- 74,948
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Apr 28, 2015
- Messages
- 251
- Tagline
- ---
Yeah! I was so pleased that I took the rest of the day off and sat on the porch listening to my old 'Free' and 'Steppenwolf' records. Plus, it was 73º here today and I decided to spend some time just sitting and looking at the lake, drinking a couple beers, and thinking about getting that amplifier completed and running this weekend. I have a Watts Abundant relay to install as well.
Purty Californy sunset just a few minutes ago.
Purty Californy sunset just a few minutes ago.
- Joined
- Apr 28, 2015
- Messages
- 251
- Tagline
- ---
I'm getting ready to install the driver board tomorrow. However, I put this thing together last year, and it has been sitting on a shelf ever since. And I seem to remember that you and Joe both said there was either something missing or in the wrong place. I may have fixed it already, but I can't remember. I think it may have been a transistor that was the issue. Does it look right to you? I'm going to go over it again tonight, but thought I'd try to get a second, third, fourth, or however many opinions.
- Joined
- Mar 18, 2013
- Messages
- 7,562
- Location
- Coventry, CT
- Tagline
- Fondler errrr... fan of all Nav's avatars