Further upgrading my first built WOPL, a 400 S1 8 fin, with a few goodies.

[mlucitt]

A short run of wire has pretty amazing inductance.

Good to know. And I keep my wire runs as short as possible. It is amazing how much wire I pull out of a PL700B.

 

[George S.]

OK, back at it for a couple hours. Removed the 22 AWG meter signal wires from the backplanes. Vacuumed the through holes out with the Hakko, then carefully and lightly soldered then shut.
Then bent a paperclip to use Sniffs swizzel stick technique to ensure no blob or short on the back side.
No more 22 AWG soldered directly on the backplanes, I like that

 

[gene french]

did you connect meters to dcp???

 

[George S.]

Yeah man, just got tasked by the wife to help her with a chore.
Here's the photo. Now the signal wires for the meters come off the DCP rather than the backplanes. Wire is 22 AWG PTFE "Teflon" insulated mil-spec silver plated. The terminals are sized to fit a # 4 stud, red is right channel, white is left.
The screws I'm using are 4-40 D-sub screws that have a nice hex head. Keystone Electronics #7229.
https://www.digikey.com/en/products/detail/keystone-electronics/7229/10127

 

[George S.]

While I have this apart again, I going to replace a black bias wire that goes between the back planes and control board. Knicked it when I stripped it and this is the result. All the wires that go to the Phoenix connectors need tinned after stripping. Watch for knicked strands.

 

[gene french]

very nice....please hang around when i am building mine...to remind me of these tips...
i am archiving as much info and pics as i can....
now i only have to remember what i archived and where to look....
lol...
getting old is a b*t*h....
very nice work....
thanks for sharing...i think your donation will be here monday...tuesday for sure....
joes stuff is in miami...but, not yet put in system....
solder and flux also monday or tuesday for sure....
gotta find a place to work...i have consumed the dining room table for quite a while...
lol....

 

[gene french]

While I have this apart again, I going to replace a black bias wire that goes between the back planes and control board. Knicked it when I stripped it and this is the result. All the wires that go to the Phoenix connectors need tinned after stripping. Watch for knicked strands.

yes sir, mr. george of the jungle!!!!

 

[George S.]

The bias transistor wiring with 6 good wires.

 

[gene french]

you gotta take care of me....
i know where you live....
lolololol

 

[gene french]

The bias transistor wiring with 6 good wires.

mine will look that nice....just wait and see....
lol

 

[George S.]

Not happy with the clearance between the meter stud and copper bus bar. Let the control board pivot out on it's wiring, and the storage cap screws are pretty much a straight shot. Loosen the screws, rotate the caps, lowering the bus bar.

 

[gene french]

Not happy with the clearance between the meter stud and copper bus bar. Let the control board pivot out on it's wiring, and the storage cap screws are pretty much a straight shot. Loosen the screws, rotate the caps, lowering the bus bar.

pic??

 

[George S.]

With the storage caps rotated, I get clearance I can live with. Now going to once again bring her up slow , and recheck bias and DC offset

 

[George S.]

So she came up nice. Now going to complete the rest again.
Gene, here's a photo of the fuse area without the cardboard installed. PL glued the cardboard in with silicone adhesive. I carefully cut the adhesive and save the cardboard for reuse, and a chassis screw retains it.
Now let's talk about those fuses. You've seen the AC wiring done, so you know the left most is Line/120 VAC. The other two you should have a idea about because earlier I talked about the two DC rail voltages.
Each + or - 80 VDC rail has it's own fuse.
So a green wire comes off the upper storage cap to the base of the fuse holder, as does a blue wire off the lower cap to the base off the other fuse holder.
The wires on the tips of these + and - 80 VDC fuse holders then go to the backplanes, along with grey ground wires from the buss bar. Remember, this is a "center tap" transformer with the center tap connected to the buss bar.
Enough of this for a while. Time to sharpen the blades on the zero turn, do some weed eating, and cut grass. Later.

 

[gene french]

i have first hand experience with the rail fuses....lol
thank you so much...
why the cardboard??
there are many places on does not need to touch....why there??

 

[J!m]

I wonder if you could get a nylon cap nut that fits those threads on the cap…

That’s what I’d probably do.

 

[George S.]

Gene, maybe if the upper cover gets pushed in from stacking components. Good chance it's something the government might have mandated. They added extra screws to the Series 2 cover, has same cardboard.
Jim, I do have some black plastic caps I had on there at one time. I think your idea is excellent. Going to grab the thread pitch gauge and find some nice nylon cap nuts. Great idea!

 

[George S.]

Checking meter calibration.
Here's how on the 400 S1.
Connect your signal generator to the RCA inputs.
Connect your VAC meter to the speaker jacks.
Input a 500 Hz sine wave starting at 1 VAC amplitude. Slowly raise the amplitude, stop when the VAC meter shows 20 VRMS.
The VU meters needles should be close to the "100" on the VU meter. This "100" means 100 watts output.
These meters are not very accurate or highly responsive to output levels.
One reason some of us prefer the WOAD Cylon meters, in the Series 2 style amps.
These meters never move or swing in the small room system I use it in.
Tomorrow, I'll put this in the big system driving the JBLs and stress test it. Will get her as warm as she has ever gotten and take her temperature at the transformer, vents, and heatsinks.

 

[Gepetto]

Checking meter calibration.
Here's how on the 400 S1.
Connect your signal generator to the RCA inputs.
Connect your VAC meter to the speaker jacks.
Input a 500 Hz sine wave starting at 1 VAC amplitude. Slowly raise the amplitude, stop when the VAC meter shows 20 VRMS.
The VU meters needles should be close to the "100" on the VU meter. This "100" means 100 watts output.
These meters are not very accurate or highly responsive to output levels.
One reason some of us prefer the WOAD Cylon meters, in the Series 2 style amps.
These meters never move or swing in the small room system I use it in.
Tomorrow, I'll put this in the big system driving the JBLs and stress test it. Will get her as warm as she has ever gotten and take her temperature at the transformer, vents, and heatsinks.

Hi George
Remember the meters are calibrated at 0dB to 50W. 20Vrms into 8 ohms is that 50W. PL did that or the meters would never get off the stops and users would think the meters were broken.

 

[George S.]

She's softly singing. Now she's dead quiet. Had a little hum before to the preamp from the amps transformer. It would disappear if I moved them apart. It's gone now.