Troubleshooting time, PL700B with new White Oak board

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Stuck in the 70's
Hey guys,
Just tried to fire up my 700 with the new WO driver board, and I ALWAYS use a dim bulb tester (DBT).
The bulb stays bright with a 100 watt bulb installed, and the main filter caps are only charging to a little over 4 volts each.
Checked and double checked my connections, all looks good.
Advice?
Thanks in advance...
Dave

PS, I just remembered that Don's dc protect circuit doesn't like to power up on the DBT. Think this could be part of the issue?
 
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Yep, you're one of us...can't stand a no issue power up eh??
 
Yep, you're one of us...can't stand a no issue power up eh??

Haa! Yeah, if there weren't problems, there'd be no need for engineers.
I'm going downstairs now to build the 2nd WO driver board and hopefully get it installed by the time the postman gets here with my WO Light Boards!!!
Then the subwoofers will be WOPL700...nah, with +/- 108vdc closer to the fabled "WOPL 1000"!
I haven't measured the power supply of amp number 2 yet. Hoping it's as hot as number 1 is.
Lee, what voltage do you need to see at the PS filters to qualify for 1000 watts?

Dave
 
You're right at it there Dave. I IRC 107 is the magic number..
 
Haa! Yeah, if there weren't problems, there'd be no need for engineers.
I'm going downstairs now to build the 2nd WO driver board and hopefully get it installed by the time the postman gets here with my WO Light Boards!!!
Then the subwoofers will be WOPL700...nah, with +/- 108vdc closer to the fabled "WOPL 1000"!
I haven't measured the power supply of amp number 2 yet. Hoping it's as hot as number 1 is.
Lee, what voltage do you need to see at the PS filters to qualify for 1000 watts?

Dave

Looks like the postman delivered Dave...
 
Looks like the postman delivered Dave...
Yes he did! Two nice ASSEMBLED LED light boards...Thank you Joe!!!
I have been soldering all day and the fruits of my labor are now powering my dream speaker system.
PL700B #2 is WOPL'ed and just getting it's first workout driving my Dahlquist subwoofers.

This sounds sooooo good.

Lee, you'll love this...PL#1 has a power supply output of +/- 108 vdc. PL#2 is...get this...+/- 110 vdc!!!
I guess I can honestly refer to these as WOPL 1000's now.
Two hotties in a row. I do believe that the good Lord has provided me with FAVOR in these two.

Now I need to order some new output transistors for #2 (It's got XPL-909's), and install the dc protect board when it gets here, plus I have two BLUE LED light boards to dress the pair up.
Need to fix a sticky meter on #1 and really need to replace the front panel and the handles on it. That amp saw a tough life, but it's electronically restored and sounding stellar.

I will be in the market for 4 new 150 volt main filter caps when the group buy comes through.

Gotta go and crank the stereo now :toothy10::toothy10::toothy10::toothy10::toothy10::toothy10::toothy10:

-Dave-
 
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Awesome!!!! I am happy for you! You got a nice pair of beasts there indeed
 
Dave - nice job with this.

I saw that you now want four caps so I updated the PL 700 Capacitor Purchase thread to reflect this.

When you get to the sticky meter could you photo document your repair?

Thanks - Dennis
 
He be in the WOPL 1000 club his first two tries, hows that for luck??
 
He be in the WOPL 1000 club his first two tries, hows that for luck??

Nav, Thanks, let me know how much I owe for those caps, and I'll do that when I fix the meter ...don't know what to expect really, and I'm hoping it's just something obvious that binds at the lower travel limit...and Lee, WOOHOO!!!
 
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I know I've said it a thousand times, and it may br getting old but a WOPL'd 400 or 700 truly are a magnificent amp. I have personnaly purchased a Bryston 4B, aN SAE 2300, plenty Spec 2's and now a Crown,. hands down no comparison, absolutely none, and this latest 400 takes it even further. Waiting patiently (ok, F&^% that--impatiently) for Joe's fully comp 700 backplane boards...
 
I know I've said it a thousand times, and it may br getting old but a WOPL'd 400 or 700 truly are a magnificent amp. I have personnaly purchased a Bryston 4B, aN SAE 2300, plenty Spec 2's and now a Crown,. hands down no comparison, absolutely none, and this latest 400 takes it even further. Waiting patiently (ok, F&^% that--impatiently) for Joe's fully comp 700 backplane boards...

Got the light boards installed today, and all new ON semi output transistors. I'm rockin now, man!
DSC_5717_3862.jpg
 
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