This was for a high-shcool classmate, so I took special interest to see that it is done properly. Originally, the set was completely dead. Found out problem to be blown Fusible 0.1-ohm Resistor and two Power Switching Transistors on the Power Board (usual problem), as well as Blown HOT and a solder crack at the Horizontal driver Xformer (again, usual problem). Replace/clean/resolder all of above. Power up using Variac and 75W bulb in 130V, checked HV in 2nd Anode using HV Probe and all that. Everything worked fine with TV facing down and case open. After putting the case back on, however, there was sound, but no raster. The LED flashed at 1 second frequency. After scratching our heads for a few minutes, we decided to open the case again. We then found that the case was interfering with one cable to the CRT-socket board, to the point that the socket board was pulled to a slanting position (as opposed to being square to the CRT neck). After we repositioned the cable and put the case back on, everything worked - for a week... My conclusion was that either the heater or the cathode pins were not making contact (Right???) I got a call a few days later that the TV has lost the raster again, but with sound and the flashing LED, just like when we found the CRT-socket board was at an angled postion before. I am going to make a house call in a few days. I would like to ask the group experts on whether I am on the right track, or are there any other probable cause for the said symptom?
Thanks, Appreciate_It