WOPL 400 Down Under

Yes Don's DCP installed and functional I presume.
I took a video of what happens but it is too big to be uploaded apparently.
The meter input leads come from the back plane so if the DCP is functional the outputs/speakers will see nothing that is shown on the meters after power is cut. Quiet speakers support my theory I hope!
My guess is that it is the POS and NEG rails discharging at different rates which is causing the issue, if I'm correct is there anything to worry about?
 
Timmienator said:
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?
Click to expand...
Timmie
That is quite normal for a stock PL400, also known as the turn off thump. Based on your thread postings so far, you still have the stock board in place. It will be more pronounced in the meters if:
  • You have the light board jumper in the most sensitive position -20dB
  • You have no speakers attached during that turn off sequence, if speakers are attached, you will hear it in the speakers and the meters will move less
 
Timmie
You just posted that you have Don's board installed. That disconnects the speakers on turn off so the turn off thump has no where to go except the meters. It is the final gasp of the energy in the bulk caps, the control board loses control when the voltage on the caps drops too low.

This is greatly improved on the White Oak Audio board, but you don't have that in place yet.

You should move your meter leads to the output of the DCP. That will eliminate any of this.
 
I got my mouser order today and in it was a roll of Kester 245.
So project "Populate Control Board" began.
Decided to do this on the front porch so all I got done was the 1/4w resistors.
Here's some pics and feedback would be appreciated from the wise!
 

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Timmienator said:
I got my mouser order today and in it was a roll of Kester 245.
So project "Populate Control Board" began.
Decided to do this on the front porch so all I got done was the 1/4w resistors.
Here's some pics and feedback would be appreciated from the wise!
Click to expand...

At this point. is a good time to ohm out the resistors note that their are some that will ohm out haft value because their in parallel (I actually ohm out groups of resistor before I soldered them w a cheat sheet I made)
I would check before clipping the ends off but made sure their not touching each other.
 
Sniffs right, too much solder, I actually see some drips coming off the leads on the component side.
Highly recommend you calibrate your iron temperature with a appropriate device or thermocouple before continuing.
Don't rush the build.
 
Last edited:
I set tip temperature at 600°f is that too low?
And I probably put too much on a few joints
 
compare
Timmienator said:
Also what does ohm out the resistors mean,it's not a phrase I have heard before?
Click to expand...
take your dvm and check ohms across each resistor to compare...some check values of components are installed to check for heat damage...resistors can take quite a bit of heat...other components not so much...
 
gene french said:
thats what i use unless its heavier work...i defer to sniff on this one...
Click to expand...


700 can be destructive UNLESS you know what you are doing. If you have a good technique and don't dwell, otherwise it is high. I say that if you are new to soldering, get a practice board and practice practice practice. Your equipment has a lot to do with it and if you are getting good flow, play around with your settings and get used to what works. Jumping straight into a WOPL is not for a beginner. We've seen a bunch of guys screw up and the job looked like ass.
 
gene french said:
compare
take your dvm and check ohms across each resistor to compare...some check values of components are installed to check for heat damage...resistors can take quite a bit of heat...other components not so much...
Click to expand...


Ohming out the resistors BEFORE installation will make sure you have the right resistor in the right hole. Once installed, you don't really know if they are correct because of parallel/series resistance within a circuit.
 
WOPL Sniffer said:
700 can be destructive UNLESS you know what you are doing. If you have a good technique and don't dwell, otherwise it is high. I say that if you are new to soldering, get a practice board and practice practice practice. Your equipment has a lot to do with it and if you are getting good flow, play around with your settings and get used to what works. Jumping straight into a WOPL is not for a beginner. We've seen a bunch of guys screw up and the job looked like ass.
Click to expand...


700 on a back plane will not be high enough due to the large ground planes wicking heat away from the joint
 
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