Johan's Phase Linear 700B Fully Comp Conversion

jbeckva

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Yep, positive and negative bias should be within 10%...let's not sugar coat it Jer, it was a SEVERE blonde moment...
Not as severe as the two 400 main caps I wired backwards the other day... heheh.

Or whatever the heck I did with that 3000 pre power supply, LOL... dayum... speaking of which I started wiring up the "replacement"... more pics comin later - pretty cool!
 

johan1212

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Lee.....seems like next BBQ party is at your place for that beautiful BLONDE moment...lol...so happy I posted that picture...and that I dont need to buy a hearing devise yet....lol..
 

johan1212

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yes definitly....no wonder ....with a bias at 160 instaed of 385....day and night...why dont you try to reroute fedex....useless to come all the way to Fl...like you want...I can send it to wherever you tell me.....but you might save like 7 daysor more by just rerouting it or calling it back...let me know....
 

laatsch55

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No Johan, not surprised at all, a 400 I have here responded exactly the same way, more like relief....
 

Gepetto

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Hold on there ... It should be yellow bias + and grey OUTPUT for the - lead. Bias - to Bias + is going to give you double the reading because bias - is measuring across the 10 ohm on the negative side. Adjusting for 380 there is going to actually give you half the bias voltage required.

Or just like he had it with one on the bias TP on the PL14, the other on the output.
Correct procedure here folks. This tells me that the bean counters can come rushing in and cost reduce by removing some of the plethora of test points provided on the backplane boards since they don't get used anyway :)

Glad you guys figured it out.

Attach the DMM negative to the GRAY output TP
Touch DMM positive first to YELLOW BIAS+ TP. Set your bias here to 380-385mV.
As a double check, move the DMM positive lead to the other YELLOW BIAS- TP and you should get very close to the previous reading. The resistors are 1% tolerance so the BIAS- reading should be within 2% of the BIAS+ reading.
 

laatsch55

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Correct procedure here folks. This tells me that the bean counters can come rushing in and cost reduce by removing some of the plethora of test points provided on the backplane boards since they don't get used anyway:-o
:stfu::stfu::stfu::bootyshake::bootyshake:
 
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