Just when you think you have it done

Mike Sweeney

AK Subscriber
Subscriber
I have a 1030 amp that I restored some months ago and it sounds great.. except for the Phono so I parked it till I had a chance to go back into it. What I found was a mis-marked board for four of the caps regarding polarity. But that wasn't the real issue. Two of the caps had not been replaced, I needed to order the axial lead version which I had just gotten around to. The other two were replaced and I got one of the two wrong because of the board and I must have misread my own marks. But the real issue was the right channel was dead.. demised.. no vroom.. I had signal going into it.. zippo out.. and really low or zero voltage on that side. All caps had been replaced.. both transistors had been replaced. After poking around and banging my head against the schematic.. I happen to have the system on it's side and some backlight.. I noticed a ring of light where there should have been solder. When I pulled a cap, I had pulled the entire blob of solder off, replaced the cap, re-soldered and overlooked that a resistor shared that blob. The lead was there.. centered in the hole without any solder on it :/ After calling myself a few names, I soldered it up and bingo, right channel comes back.. ::sigh::: all is right in the world now :)
 
Mistakes happen. We can replace 100 components and get them all right. Then 101 gets installed incorrectly.

Just a few weeks ago, I had basically no output from one channel of phono board that I had re-caped\transistors. When I pulled the board for checking, I found I failed to clip a lead off of a new cap, and that lead was naturally pressing up against chassis, grounding the channel. Doh@!
 
Reminds me of a dental school anecdote from many years ago. Taking an oral surgery course and the instructor was going to teach techniques for dealing with broken roots. He said, “ If a dentist ever tells me he’s never had a broken root, I know right away that either he’s a liar or he hasn’t taken out many teeth”. Same pretty much holds for soldering errors. Someone says they’ve never made one — they are either lying or haven’t done much soldering.:D
 
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