This is the first time I've run into this situation, so I'm not sure exactly how to ask.
I'm working on an arcade monitor (Sanyo 18-Z2AB), which had vertical collapse. I believe I've located the issue as bad electrolytic capacitors and two of the vertical deflection transistors (TR402 and TR403).
After researching and asking around, a few of the more experience repair techs mentioned when you replace the transistors:
My question is: Since I would have NEVER have thought of this when troubleshooting the monitor, how could I have found this out on either the schematic (see below...there's no indication of this...unless I completely missed it), or is there trick/best practice to find this out? Is this common practice? Is this a product of a "hot chassis?"
Appreciate any wisdom, insight, or reference material.
I'm working on an arcade monitor (Sanyo 18-Z2AB), which had vertical collapse. I believe I've located the issue as bad electrolytic capacitors and two of the vertical deflection transistors (TR402 and TR403).
After researching and asking around, a few of the more experience repair techs mentioned when you replace the transistors:
- Make sure you replace it with a metal package (the collector part) and not a full plastic package
- Don't use a mica or silicon heat insulator, just thermal paste because the heat sink electrically completes the circuit. This is a common comment and is proven when someone does put in something to electrically isolate the transformers from the heatsink, vertical deflection fails. When they have the transistor electrically connect to the heatsink via paste, it works.
My question is: Since I would have NEVER have thought of this when troubleshooting the monitor, how could I have found this out on either the schematic (see below...there's no indication of this...unless I completely missed it), or is there trick/best practice to find this out? Is this common practice? Is this a product of a "hot chassis?"
Appreciate any wisdom, insight, or reference material.