tech support
Post count: 46
  • Offline
#698 |

Hi Tony

All solder joints are suspect and it’s not really a reflection on the Manufacturer, the steel or alloy used on the devices is much harder and has a higher melting point than the solder so you never really get a weld whereby the metals intermix, the best you ever get is a really tight fit, and with the heavier components, movement allows inertia to pull at this tight fit and eventually you see a weakness developing, this is then attacked at a microscopic level by carbon deposits and such as the current attempts to flow through the connection this gradually compromises the conductivity of the connection and a vicious circle develops. This can happen with any joint but is usually worst on the heavier components given Inertia and the typically higher current transfers involved.
The fault with your TV is thermal so we are either looking at a device breaking down as it reaches operating temperature, or a poor joint/connection failing as it expands with heat, the freezer will be better at highlighting a failing component and will hopefully narrow the search area, the answer to a poor joint is really just close scrutiny and perseverance,

On the up rating from 5 watt to 10 watt on the resistors, this will enable the resistors to run cooler, which is not a bad thing, but unless they are increasing in value with heat it’s unlikely to be a solution, as they will be larger than the originals and may still run hot, make sure that they are not too close to any plastic cabinet surfaces when the TV is reassembled,

enjoy your weekend Keith, the UK is forecast for 5 consecutive dry days, that constitutes a Summer here,

kind regards,