Dear Friends !.
The PFG driver on our Varian Inova-500 is showing error indication
(LED glowing). The PFG driver is Highland make, model # L600. After
having basic tests (fuses ..etc) done, I realized that the two
transitors Q5 (2N4402) and Q6(KN4400) in the FG driver are blown off.
I replaced with equivalents 2N-4403 and BF-337, respectively. However,
the problem is not solved. As soon as the mains is ON, the Q5 blows!.
I tried to figure it out where could be the "short" and failed to do
so. We donot have any schematics for this PFG unit. Please let me
know, if you have some suggestions to solve this problem.
PS: Today I saw on E-bay that some one has placed L600-PFG Driver
for aution. Unfortunately I could not access it. Please let me know ,
if any one of you would like to give away this item.
THANK YOU IN ADVANCE
sincerely-- Jagadeesh
Dr. B. Jagadeesh
Scientist, NMR Center
Indian Institute of Chemical Technology
Uppal Road, Hyderabad 500 007 (AP) India.
Phone: +91-40-2716 0123 ext 2601 ; +91-40-2719 3976
FAX : +91-40-2719 3108
Received on Wed Apr 20 2005 - 17:25:39 MST