The 10" LX200 has been balky, failing to boot up. Pulling the bottom plate, I found the possibility that the aluminum bottom plate was contacting some resistors. My solution involved the heat sink on the SIP chips. The standard LX200 Classic's heat sink is too small for the job. A previous electronics repair job had resulted in an aluminum 3mm thick custom heat sink. However, it was so thick that the pressure on the bottom plate during seating on the tripod was probably putting a lot of stress on the chips' connection to the motherboard. My solution was to buy a 1mm thick piece of copper at Orchard's Supply Hardware, some 4x40 brass screws and matching nuts. The base of the LX200 supports the bottom plate so that the bottom plate won't touch the motherboard components. The supporting places are at the edges all around, at the two interior pads, and also spanning across (except for a middle section) the diameter of the base just outboard of the SIP chips. I cut the copper piece so that it would bridge across this span with enough overlap to provide a rigid support so that pressure on the bottom plate would mostly be transmitted to the base and not to the SIP chips.
The copper heat sink also rests on the shoulder of the two tabs at the left and right end of the copper, on this photo. The brass screws were flathead, countersunk so minimize their profile |
I enlarged the existing holes so that the screws through the SIP chips didn't get weight when placing the scope on the tripod |
