phase linear 400

Gepetto

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Put a temporary jumper between the bias transistor C-E, that should zero your bias. If it does, the issue likely resides in your bias transistor. If it does not zero it, then your issue is elsewhere. It is important to note that it is perfectly safe to run your amp with a shorted C-E on the bias transistor. It is NOT SAFE to run your amp with an open C-E condition on the bias transistor.
 

Sunnbobb

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Did you replace the the 10 Ohm resistors -YES
What is the voltage on R25 - AROUND 7V, however, tough to get a measurement given i have about 4 seconds to work with.
If you lift on leg of D12, does R25 still get hot? - N0 LONGER GETS HOT
Remove the yellow wire on the control board for the Right channel - R25 gets hot AND R23 pretty much burnt up immediately. Replaced R23, hooked yellow wire back up. R25 gets hot, bias .550.
Bias transistor jumper test - bias remains at .550 and R25 gets hot.
 

gene french

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guayabo de bagaces, guanacaste, costa rica....
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Did you replace the the 10 Ohm resistors -YES
What is the voltage on R25 - AROUND 7V, however, tough to get a measurement given i have about 4 seconds to work with.
If you lift on leg of D12, does R25 still get hot? - N0 LONGER GETS HOT
Remove the yellow wire on the control board for the Right channel - R25 gets hot AND R23 pretty much burnt up immediately. Replaced R23, hooked yellow wire back up. R25 gets hot, bias .550.
Bias transistor jumper test - bias remains at .550 and R25 gets hot.
i hate it when that happens ....
 

Gepetto

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well, dont remember how long ago i ordered the light board for the last pl400...
but, it arrived today....i am sure it was more than a month...
welcome to costa rica!!!!
will install tomorrow...and wrap that puppy up!!!!!
April 2nd, 16 days ago. You probably use that same line when you tell Maria what 6" is too :)
 

gene french

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guayabo de bagaces, guanacaste, costa rica....
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music...the healer of souls...
April 2nd, 16 days ago. You probably use that same line when you tell Maria what 6" is too :)
you dog!!!
lololol
i can get away with it ....theyre on the metric system!!!
lololol
but i ordered before that...you didnt invoice right away!!!
ome thing i have acquired...patience...this country sure tests you for that...i am a lot happier when accept that it will be here when it gets here!!!
finally growing up at 74!!!
lololol
thanks mr. joe...this experience has been vrry rewarding!!!!
 

gene french

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guayabo de bagaces, guanacaste, costa rica....
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music...the healer of souls...
burned off a section of the property yesterday that
we cleared over the past few months...is common practice here because the place is not conducive to traditional mowing....too rough...too many boulders from volcanic activity in the past....so many people called or came by to see if i needed help...i was humbled by the generosity of these people and their affection for me and my family....
 

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gene french

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guayabo de bagaces, guanacaste, costa rica....
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music...the healer of souls...
done...new l8ght board installed....
all units up...running...lit up!!!
using 4 pl400s.... 2 spares...
working on meters for haflers...one more to do...
its been interesting!!!
forgot pic...this is my original wopl!!!
 

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gene french

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guayabo de bagaces, guanacaste, costa rica....
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music...the healer of souls...
question...i live in a tropical climate within a few miles of an active volcano..with no humidity contril...ie a/c...i seem to be having issues with connections / switches....i use gold plated plugs/cables...but on occassion they lose contact...a slight twist / switch recycle gets me back in business...is there something i can coat the jacks/plugs with to help...
 
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