There is no fan. It is a Sony chassis with a Sony picture tube. The model number is D2026T-HS. G2 is definitely connected to the transistor, but does not go through the transistor to get to the CRT. The transistor checks good. I want to change the resistor, but I can't find one so far. Kevin Wilks Kevin's TV & Video Repair Penticton BC Canada kevintv@xxxxxxx -----Original Message----- From: techassist-bounce@xxxxxxxxxxxxx [mailto:techassist-bounce@xxxxxxxxxxxxx] On Behalf Of Gary McCartney Sent: Monday, January 31, 2005 2:23 PM To: techassist@xxxxxxxxxxxxx Subject: [TechAssist] Re: Dell Ultrascan 20TX, 1997 19" computer monitor, low screen voltage, need schematic Kevin, is there a fan in the unit? If so the fan might be dead, causing the shutdown. Also, try changing that 2.2 meg resistor even though it checks ok. I'm not really familiar with the circuit, but it sounds a bit strange that there is a transistor connected to the G2. Can you verify that? Is the transistor pulling the G2 down to 4V? Are the any other model/ chassis numbers? It might be a Sony chassis. Gary McCartney McCartney Electronics Guelph Ontario Canada Est. 1984 email: gary (at) number63.ca Kevin wrote: > This monitor comes on with HV, filaments, and no video for about 5 > seconds and then it goes into shutdown with an amber light flashing. > The screen voltage or G2 measures only 4 volts and then drops to zero > when the monitor goes into shutdown. I found 790 volts on one end of > R463 and 4 volts on the other end. The 4 volt side is connected to G2 > on the picture tube and to the collector of Q403, a C4686 transistor. > R463 measures correctly out of circuit at 2.2 meg ohms. > > Kevin Wilks > Kevin's TV & Video Repair > Penticton BC Canada > kevintv@xxxxxxx > > > > > ------------------------------------------------------------------------ ----- > Lost Password: > http://www.tech-assist.org and select "Login Problems?". > Email Archives: > http://www.freelists.org/archives/techassist/ > ------------------------------------------------------------------------ ----- Lost Password: http://www.tech-assist.org and select "Login Problems?". Email Archives: http://www.freelists.org/archives/techassist/ ----------------------------------------------------------------------------- Lost Password: http://www.tech-assist.org and select "Login Problems?". Email Archives: http://www.freelists.org/archives/techassist/