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Old 1st May 2009, 5:30 pm   #113
stonehopper
Retired Dormant Member
 
Join Date: Apr 2009
Location: St Albans
Posts: 50
Default Re: Roberts RT7 - problem

I'm back.
Further to the collector emitter connections; I have traced the OC81's (TR6 & TR7) on the board and can confirm that the collectors both go to one side of the transformer T2 but to different terminals, and also that the TR7 collector goes to the base of wax C33. Whereas the TR6 collector also goes through R30 and on to the top of wax C33.
The TR6 & 7 emitters both go to different terminals on the other side of T2.
The TR6 & 7 base are connected to different terminals on one side of the T1 driver transformer.

These shots of the base make it look pretty grim. But my camera seems to pick up things that I cannot see with the eye - even with two pairs of glasses on!
Some of the holes are unused, checking with the service sheet shows no components in those locations. What looks like solder spatter possibly is, but the whole board seems to be lacquered over - spatter and all. The repaired track is far left - first inside the boundary track.
The empty holes far left, top left, are the removed TR6,7, & C32, there are two more where the R26 & R27 have been lifted one end.

PS The orange wire floating around was removed for access to R26.
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