WOPL 400 Down Under

[wattsabundant]

Better yet, read the P/L service manual on how to test outputs. Keep in mind this was written before digital voltmeters with the diode range were introduced

 

[MusicSteve]

suggestions steve???

Go back to post #65 and #66
than remove the resistor on D8 (Right and left) and what kind of meter do you have
Next step will TBD when you have time.
Picture of testing a Diode

 

[Timmienator]

Steve
I forgot to mention the diode readings I posted the first number was forward bias and the second reverse bias. I don't have a Fluke but it is a true RMS dmm, yes it's Chinese but it wasn't a cheap one at $150AUD.
And we all know that everything is now made in china, except babies they are made in va-china!
I have remembered that I have a working amp here so I will get some readings from that and compare the results.

 

[Timmienator]

Today I felt like a kid on Xmas day when I got home from work and found this waiting for me!
So excited I will somehow get over the postal service here being so shit.
The packaging of the gear for shipping was faultless as is the the individual component packaging. It seems Joe has thought of all the little things that ensure customer satisfaction and confidence, something I believe is rarely found in the current business sector.
I starting it off tomorrow after work by replacing the light board and power caps in my original 4 finner first. I am in the process of finalising my next order from Joe so will do the BR upgrade when I get the snubber kits with that order.
The question I want to ask is what is the recommendation on the best board to start constructing for a first timer like me?
Anyway here's the pics you all keep telling me you want to see.

 

[gene french]

Today I felt like a kid on Xmas day when I got home from work and found this waiting for me!
So excited I will somehow get over the postal service here being so shit.
The packaging of the gear for shipping was faultless as is the the individual component packaging. It seems Joe has thought of all the little things that ensure customer satisfaction and confidence, something I believe is rarely found in the current business sector.
I starting it off tomorrow after work by replacing the light board and power caps in my original 4 finner first. I am in the process of finalising my next order from Joe so will do the BR upgrade when I get the snubber kits with that order.
The question I want to ask is what is the recommendation on the best board to start constructing for a first timer like me?
Anyway here's the pics you all keep telling me you want to see.

congratulations!!!!
good luck!!!

 

[George S.]

Cool! Rule #1, don't rush the build. You've purchased what is most probably the finest kit in existence! Really look over the PDF files Joe sent you and recognize the difference between complementary and quasi complementary. Plenty of photos and narrative in the WOPL building section of this forum. Any questions, please ask. Many of us here have built these. Some have built many.
I would suggest looking closely at every photo you can find before you start. Pay particular attention to the wiring, how it lays, how it runs. The wiring is the most difficult part of the build. Have fun! And don't rush it!

 

[George S.]

Oh, your question. Most start with the control board, then the backplanes. The backplanes are harder to solder because the PEM nuts take more heat and the gold cups are so small and easily dropped and lost forever. Notice there are two configurations you can build the control board. Get it correct the first time. Read and look at many photos before you begin. Please ask any questions. Everyone here wants you to be successful. The time difference between the US and OZ may delay a answer, but we'll help.

 

[MarkWComer]

Today I felt like a kid on Xmas day when I got home from work and found this waiting for me!
So excited I will somehow get over the postal service here being so shit.
The packaging of the gear for shipping was faultless as is the the individual component packaging. It seems Joe has thought of all the little things that ensure customer satisfaction and confidence, something I believe is rarely found in the current business sector.
I starting it off tomorrow after work by replacing the light board and power caps in my original 4 finner first. I am in the process of finalising my next order from Joe so will do the BR upgrade when I get the snubber kits with that order.
The question I want to ask is what is the recommendation on the best board to start constructing for a first timer like me?
Anyway here's the pics you all keep telling me you want to see.

I envy you- these projects are a lot of fun, and the sense of accomplishment when it’s finished can’t be beat!

 

[MarkWComer]

Two snags to worry about:

There’s very little clearance between the backs of the backplane boards and the back of the cabinet- be sure to trim the leads on the solder side very close or they’ll short out.

There’s also not much clearance between the backs of the VU meters and the power caps- you won’t realize this until you start to close the cabinet.

 

[George S.]

And don't overlook Marks WOPL building videos on YouTube!!!!

 

[MarkWComer]

And don't overlook Marks WOPL building videos on YouTube!!!!

(I wasn’t gonna shamelessly plug myself…)

But since you mentioned:
https://m.youtube.com/playlist?list=PLYiWdKX5NXBLLWKWuje8a7hZq_tqUOMFL

The videos are old and don’t cover the newest versions of the circuits, but are still pertinent. Also on my channel is how to make a cheap-o DBT test rig. Another playlist covers the PL400 series two, but the vids are crummy and too long to watch.

 

[gene french]

and another one will NOT bite the dust!!!
go guys go!!!

 

[Timmienator]

I replaced the light board on my original 4 finner today and am very happy with the results!
By far the easiest upgrade I have done so far although I did need to use 3 spacers to get board at the right height for the LEDs.
I also realised why the original pl18 stopped working suddenly a few months ago upon seeing the board. How does this happen with no vibration etc?


Checked offset and bias whilst in there and here are the results
Left DC offset 1.8mV
Right DC offset 7.2mV
Left Bias 372mV
Right Bias 349mV

The left Bias is very stable at that value however the bias pot has no more movement to go any lower.
I know the WOPLs should be around 380mv but what about stock units?
And should I raise the right channel to match the left seeing we are in spec?

Also I would like to install a switch for the meter sensitivity however don't really want it mounted on the chassis. Has anyone done this or have any suggestions?

I didn't change the PS caps as I will wait for the snubber kits ordered from Joe to minimise stress on the old girl.

 

[gene french]

there are jumpers on the led board for meter sensitivity...10 watt 50 watt 100 watt...
default is 50 watt...
i put the switch on mine....

 

[Timmienator]

Did you drill the chassis and mount it gene?

 

[gene french]

on two of my units yes...
on the new chassis i bought from joe...it was already drilled....
i liked the location....so i drilled the other two to match...
really easy to do...
joes position is half way between the output posts and the input jacks...in that vertical line...
not really dangerous to drill...if you remove the dc protect board first...
which is not a big job at all...
please wait 5 minutes after you power down... as the caps hold the voltage about that long...or discharge the caps...
ask me how i know...
joe includes the wiring for the switches...another first class treatment...
you just need a dpdt center off mini bat switch...
take your time...pics are your friend...especially if you disassemble something...
plenty of smarts here....they saved me more than once...
good luck...

 

[Timmienator]

Thanks gene
Just had a look at one of the boards I haven't installed yet and saw the moveable jumpers!
Dumbass move by me yet a cheap lesson in the checking and cross checking needed when populating the control board and back planes.
Anyway the switch is not needed for me as I will rarely change it so the jumpers are perfect.
Most of the time the handbrakes are here(wife and kids) so volume is low. I figured now that I can actually see the meters I might as well see them move.
I guess when it does get cranked up the meters won't be harmed if they are constantly in the red?

 

[gene french]

Thanks gene
Just had a look at one of the boards I haven't installed yet and saw the moveable jumpers!
Dumbass move by me yet a cheap lesson in the checking and cross checking needed when populating the control board and back planes.
Anyway the switch is not needed for me as I will rarely change it so the jumpers are perfect.
Most of the time the handbrakes are here(wife and kids) so volume is low. I figured now that I can actually see the meters I might as well see them move.
I guess when it does get cranked up the meters won't be harmed if they are constantly in the red?

those meters are pretty tough i am told...they can be damaged if high output and 10 watt meter setting...
i like the 10 watt setting...my speakers are very efficient and play loud at low volume setting..
needle only bounce around in 10 watt mode...

 

[Timmienator]

I just unplugged it to open it up and approximately 2-3 seconds after power off the meters jumped close to the 0(red zone) then very slowly went back to resting state.
Is this a normal thing because I don't remember seeing it before?

 

[MarkWComer]

I just unplugged it to open it up and approximately 2-3 seconds after power off the meters jumped close to the 0(red zone) then very slowly went back to resting state.
Is this a normal thing because I don't remember seeing it before?

I don’t think that’s normal…
When I first received my 700 and played around with it, I hooked up an iPod to the inputs and connected my beater speakers. Played it a few minutes, then turned it off. It played for a few seconds until the power caps discharged. Still, I don’t think there would be a “kick the bucket” impulse to the meters without an active signal source.