WOPL 700B Has more output on the left channel.

Gepetto

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#62
While you are in there, change out
From Revision E2 to E3

Reason: Decrease sensitivity of the SOA protection circuit to eliminate false tripping with low impedance loads.

Change R25L/R, R26L/R from 56K ohms, 1/4W, 1% to 13.0K ohms, 1/2W, 1% small form factor.

Noticed that the board was still at the RevE1 build level. Not your problem but while you are in there.
 

Northwinds

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#66
Welcome Mohawk!

I am from the Mohawk Valley, are you in upstate NY or Canada? We lived near the St Regis Reservation when I was a kid. Lacrosse played the real way, if you did not have broken bones and covered in blood after a game, you were not playing LOL

I am 1/8th Mohawk BTW

Sorry about your issues with the WOPL. This is why we only recommend a pro build from builders here, these are not for people who think they can build amps. I have yet to see a joeblow built WOPL amp that actually works or has any type of longevity. Hopefully with help here, you will get it running right

WOPLsniffer is a great guy and friend, he just tends to be blunt and in text that can be miscommunicated when he is just trying to crack a joke. Perry is probably one of the top builders of these amps period. The very best builders are here on this site, do not trust anyone else who is not vetted by trial by fire. If the builder is not confident in their work enough to offer a lifetime guarantee then avoid. Saving a few dollars just means more money to treat the headaches that will follow

A good friend of mine got taken to the cleaners by a shit build recently (hence the Edroom reference). I am no tech but even I can see this is a somewhat questionable build
 

Mohawk

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#67
Hello,

Thanks for taking the time to respond ... EH' :) .... I really appreciate all the input that I have received on the forum. I did take issue with what seemed to be a condescending and self righteous attitude, and I just wanted to put it out there that I didn't see it as anything constructive or helpful...
We all have to start somewhere , Anyhow that's all, I'm fine leaving it at that .....

As far as the 700 goes I need to bring it up to pro standards , agreed !
If you looked at the early pics, Just cleaning the flux off everything makes a world of difference ......
I'm taking notes as I read all the responses..... I will make changes as members post to the thread and post the results !

M
 

Mohawk

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#68
Hello everyone ... I have made it back .. Finally .... The last couple of weeks have been crazy..
I hope you all can jump back in on this !
Anyhow, I powered up the 700 today to get back at it and panel lights came on but no click of the relays this time...
I found 107 VDC on the Left speaker out and 0 VDC on the 15+ test point. The 15- test point is -15.4 VDC ...
Found F1 pico on the right side back plane open, changed it and it blew right away....
 

grapplesaw

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#71
Hello everyone ... I have made it back .. Finally .... The last couple of weeks have been crazy..
I hope you all can jump back in on this !
Anyhow, I powered up the 700 today to get back at it and panel lights came on but no click of the relays this time...
I found 107 VDC on the Left speaker out and 0 VDC on the 15+ test point. The 15- test point is -15.4 VDC ...
Found F1 pico on the right side back plane open, changed it and it blew right away....
Have you checked the clearance between the chassis and wire solder joint from back plane to the board going to control board. I use a 90’ Pringle’s pick to feel under the solder hounds to make sure the wire does not extent to the chassis. I found out the hard way on this one years ago.
 

WOPL Sniffer

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Screw it
#72
Have you checked the clearance between the chassis and wire solder joint from back plane to the board going to control board. I use a 90’ Pringle’s pick to feel under the solder hounds to make sure the wire does not extent to the chassis. I found out the hard way on this one years ago.

Who you callin solder hounds HUH?

Pringle Prick???? Ewe
 

WOPL Sniffer

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#74
Good thought ... but all good..... All wires were trimmed and checked with a straight edge across the pem nuts..... Lots of clearance
I said that too..... I had to remove the back planes..... I missed one.......... Been a while since that happened.
 

Mohawk

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#76
Back in business ! And you are right on the money...... I misplaced the hex nut I removed for the upper standoff and the only one I could find to replace it was one with the integral star washer....... See where this is going ?? Propped the board up "loosely" just to hold it up and the tip of the washer was touching to heatsink for the upper T0 220 power supply transistor.... ARG...... oopsy..... Now fixed....
Bias voltage is steady @ 360 mv both sides ...... I measure +15.25 & - 15.79 at the test points... Shouldn't they be identical #'s ?

More tests to follow !

M
 

Gepetto

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#78
Back in business ! And you are right on the money...... I misplaced the hex nut I removed for the upper standoff and the only one I could find to replace it was one with the integral star washer....... See where this is going ?? Propped the board up "loosely" just to hold it up and the tip of the washer was touching to heatsink for the upper T0 220 power supply transistor.... ARG...... oopsy..... Now fixed....
Bias voltage is steady @ 360 mv both sides ...... I measure +15.25 & - 15.79 at the test points... Shouldn't they be identical #'s ?

More tests to follow !

M
Tolerances exist in life and no 2 voltage regulators will ever be the same except by serendipity.
 
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