phase linear 400

57 volts is what you get without your caps in line....

A good rule of thumb to figure rectified DC voltage from transformer secondaries is --Transformer secondary voltage X (timesa) 1.4 minus 1 volt for the diodes...---57 X 1.4=79.8- 1= 78.8....
 
Gene, the aluminum plate came from Joe with the cap kit. He provides a short piece of threaded rod that threads into the cradle, and the plate drops onto that rod and is secured with a lock washer and nut, finger tight. Holds the caps securely.
The rectifier mounts on the same rod under the plate.
 
Last edited:
laatsch55 said:
57 volts is what you get without your caps in line....

A good rule of thumb to figure rectified DC voltage from transformer secondaries is --Transformer secondary voltage X (timesa) 1.4 minus 1 volt for the diodes...---57 X 1.4=79.8- 1= 78.8....
Click to expand...
Lee, thank you!!!
 
George S. said:
You can always run the same B+ and B- test on your other amp just to verify the test procedure. If you do, also see what VAC your getting off the secondaries.
The go back and carefully see what the problem transformer has for VAC on the secondaries.
Sounds like the rectifier is good.
Click to expand...
i will compare to the 8 fin tomorrow!!!
 
gene french said:
all 4 legged diode test was fine in all positions....showed 4 one way conducting diodes
input ac was 123 volts...
i did not put in the new rectifier yet....
retested using existing rectifier...no change...plus and minus 57 volts....
i even plugged outside of the dbtester...no difference??
do you suggest tomorrow i test using the new rectifier???
Click to expand...
57vrms AC rectifies to 80.5vDC
 
George S. said:
Gene, the aluminum plate came from Joe with the cap kit. He provides a short piece of threaded rod that threads into the cradle, and the plate drops onto that rod and is secured with a lock washer and nut, finger tight. Holds the caps securely.
The rectifier mounts on the same rod under the plate.
Click to expand...
Gene will see on his next cap kit George...
 
gene french said:
yes sir, i certainly will!!!
mr. joe
all 3 sets of meters are tinted....
do you think the yellowish one would be illuminated better???
or am i better off with the clear one???
Click to expand...
All the meters have a tint to them. Some early 4 fin units had a very dark tint to them and I believe you have one of those in the first unit you upgraded.

The meters you just pictured look like the bulk of PL meter, the pictures a page before look like the stock Jewell meters with the slightly tinted lenses. Those are what I have in all my amps and I run the warm white illumination.
 
i just wrote to rob...and thanked him...his machines were exactly as he described....i did explain...there are many things i do not / did not understand...but you guys all pulled together to help me understand and learn...i want to thank joe again for hooking us up....i was treated fairly...i do appreciate....
life is good...and getting better each day!!!
will fire up the 8 fin tomorrow...and let her stew a while...joe should be shipping more stuff very soon...i am super excited!!!
 
Checking the rectifiers output, + and - 80 VDC. No caps installed.
 

Attachments

  • PXL_20220516_011813938.jpg
    PXL_20220516_011813938.jpg
    2.7 MB · Views: 14
My question about the outputs is, if I remember correctly, on both amps all the bottom transistors were all Toshiba's while the top 3 in each channel on both amps were PL transistors. Are these bottom transistors Pre-Drivers? I can see in the diagram that Q13 thru Q18 are PL909's and Q11 and Q12 are listed as 66546 transistors or SJ2741 noted in the diagram below.
 
Last edited:
Gene, From my understanding over the years when talking about outputs and lot #'s. When buying a set of outputs I would hope they are a matched set. But in the photo below the Toshiba has an R designation. you want to keep the same letters together because of the GAIN and other characteristics. Its just a better performance when doing that. If you put R's and O's together the amp will work but I like to keep that from happening.
View media item 32383
 
You must log in or register to reply here.
Back
Top