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Chuck[_27_] Chuck[_27_] is offline
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Default Painting a Bakelite radio cabinet

On Fri, 29 Sep 2017 05:23:32 -0700 (PDT), "
wrote:

A bit of history might help you understand things. Once upon a time, light switches and receptacles were designed to be able to handle AC and DC. What happens when switching DC? Arcing. So, switches and receptacles, and switches in everything from lamps to toaster had to be arc-resistant. In addition, manufacturers did not have 100 years of historical data to design from. So, things were over-designed (by modern standards), heavy (by modern standards) and many have withstood the test of time and survive to this day. Today, switches are either AC or DC, designed to very specific standards, and as long as they are used within those standards, will also last indefinitely.

Capacitors started as foil-and-glass devices, evolving to foil-and-paper (cheap) sealed with paraffin wax + some bees wax for workability (cheap), and some were potted in tar (even then, manufacturers understood that the materials had self-decay problems) and various other methods were tried - and discarded over time. BUT, remember, EVERYTHING WAS NEW back in those days. Nobody had 100+ years of data to use, and what we understand today as being very short blind alleys were enticing options. So, there is a LOT of crap out there that was perfectly functional when made. Electrolytics evolved similarly and improved similarly. As did resistors, even tubes. Nuvistors, developed about the same times as reliable transistors, were thought then, and perhaps still, to have a pretty-much indefinite service-life as compared to a standard tube.

So, now the evolution of consumer-grade electronic components, caps, resistors, transistors, and so forth, has made them into commodities based on unprotected (no patent protection) technology using cheap-as-hell materials and largely automated manufacturing processes operating at a precision that was not possible back-then. Meaning that a Visay-Sprague has no competitive advantage over the Grace L. Furgeson storm-door and capacitor company, or the Wa-Chen capacitor company operating out of a garage in Shanghai. But that Wa-Chen capacitor is superior in every way to the Sprague wax-paper cap produced in 1947. Or that plastic-encapsulated cap produced by Philco in 1961.

You really need to step back and take a 20,000 view of this hobby. Don't plant your feet 'back in the day' as you *DO* have 100 years of data to pull from, and you *DO* have the opportunity to bypass the mistakes of others and go directly to the proper solution. There is not one person in 20 that understands the sequence of events necessary for the lamp in their ceiling fixture to light up at the flick of a switch. They take it for granted. Back in the day, that simple result was the nearest thing to magic the world had ever experienced. If you understand how we got here, you need not repeat the mistakes, or duplicate the errors, or repeat the learning process as experienced over the last 100 years. Save yourself the pain.

Otherwise the appearance of idiocy you seem to cultivate so carefully may, in fact, be your reality. That would be sad.

Peter Wieck
Melrose Park, PA


I agree with everything you say except for nuvistor reliability. We
were constantly replacing them in RCA tuners back in the early 70s.

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