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          Most of us have in our minds the picture of a quiet, well organized assembly line with highly-trained, dedicated, skilled electronic technicians carefully assembling jukebox amplifiers with precision and confidence, right?  Nothing could be further from the truth!  For the most part, the workers didn't even know what a capacitor was, much less what it did.


          In the past 20 or 30 years, I have found an unusually high number of mistakes in juke amps.  Everything from bad solder joints, NO solder joints, wrong parts, missing parts, parts installed backwards to items that shouldn't even be in an amp.In most cases, these amps didn't work very well even when new, and certainly gave a lot of trouble while they were on location.  This could go a long way in explaining why there's an occasional find of a jukebox with only 10 or 20 thousand plays on it sitting in a warehouse.  It's possible that it gave so much trouble on the route that the operator gave up and pulled it back into the shop.  Afraid to pull parts from it for fear that he'd spread the trouble like a virus, he just let it sit.  Which brings me to a short story.


          During the mid 60s, a college friend of mind took a job as a quality control inspector for RCA at their plant in Indianapolis.  Bob was the laid back type, not really taking his job seriously, but was very surprised at what he found.  At the time, RCA was the leader in color TV manufacturing.  Almost all sets were based on the RCA design.  A long assembly line was set up on the factory floor to carefully assemble the sets.  Only they weren't carefully assembled.


          Bob said that the various components that went on the circuit boards, such as capacitors, coils, small integrated circuits and so on were re-named by the workers as lumps, trees, spiders, etc.  They had no earthly idea WHAT they were assembling, much less what the parts did.  Bob related that when the workers would run low on certain parts, they would stand up and scream "I'm out of LUMPS", or trees, etc. He tried in vain to explain to them what the parts were, and what they did, but all the workers cared about was when break time or lunch was.  He said that the reject rate on the boards was almost 50%!  Parts were being installed in the wrong places, or even not at all.


          Now I'm not saying that the workers in the jukebox plants were this bad, but remember that assembly line work is very boring and tedious.  A skilled technician would go nuts in a very short time, so they simply hired people off the street to do the job and put one person over them to try to keep everything in order.  One person cannot keep up with 15 or 20 unmotivated workers, so mistakes were bound to slip through undetected.


          I have no idea of what the ratio was, but it seems that around 1 in 20 amps has a factory assembly problem.  This holds true regardless of when the amp was manufactured, but in general the amps made in the late 30s and 40s don't seem to have near as many defects.  Perhaps the quality control was better then, or the workers took more pride in their work.