Heathkit SB-1000 Design Defect

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I have an SB-1000 on the workbench with a few problems, the original builder did an excellent job of soldering and assembly but he made one critical mistake in soldering in the Tank Coil. He basically made the overall length too short and literally shorted out some of the turns. The end result was that on the upper bands he had nothing but problems and ended up destroying the original tube. It seems like after a few weeks he put the amp in a box and there she sat for at least 25 years until he went SK and another ham who bought it from his XYL sold it to me.

Among the more commonly known problems with the SB-1000 that can be corrected I noticed one design defect that had caused the second owner to ditch the amp immediately. The Rotary Meter Switch is attached to a circuit board and that switch is the only thing supporting the board. The switch itself is designed to be reconfigurable and therefore opens up very easily to allow the wipers to be moved for different kinds of operations. The problem is the same ease with which it can be opened lends the switch to being jarred apart if the amp is boxed and shipped. Normally not a problem that would occur but because Heathkit used the switch to support the whole meter board it can easily fall apart sending bearing, wipers and other parts flying. The second owner sent me the amp with various switch parts lying in the amp.

Here is a picture of the Switch after I put it back together. I then added in a support post to hold the board in place so that this would not happen again

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If you own an SB-1000 I highly suggest that you add some extra support for the Metering board and take the strain off of the switch.

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