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Apropos of nothing -- and Class D amplification

mhardy6647

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#1
I was looking up something else entirely (the history of the IHF specs for FM tuners :) ) in the wonderful resource that is www.worldradiohistory.com and I happened to notice Part 2 of an interesting two part article series in Audio magizine in 1963.

1613844336134.png


Now -- yeah -- I know Class D amplifiers have been around for a while, and -- yeah -- I know that the D doesn't stand for digital ... but, dang, 1963 was a while ago now. :)

Just thought it worthy of mention:
source: https://worldradiohistory.com/Archive-All-Audio/Archive-Audio/60s/Audio-1963-08.pdf
 

DonH56

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#2
Class D was invented in the 50's... And yes, D was just the next letter in the line of amplifier classes as they were invented and defined (A, B, C, then came D).
 

SIY

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#3
I was looking up something else entirely (the history of the IHF specs for FM tuners :) ) in the wonderful resource that is www.worldradiohistory.com and I happened to notice Part 2 of an interesting two part article series in Audio magizine in 1963.

View attachment 113779

Now -- yeah -- I know Class D amplifiers have been around for a while, and -- yeah -- I know that the D doesn't stand for digital ... but, dang, 1963 was a while ago now. :)

Just thought it worthy of mention:
source: https://worldradiohistory.com/Archive-All-Audio/Archive-Audio/60s/Audio-1963-08.pdf
Norman Crowhurst also published his version. Half the article was bitching about how well it worked but that no-one seemed interested in commercializing it.
 

DonH56

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#4
It took a while for decent high-power switching devices to be developed, along with some circuit design tweaks that got us here today.

Totally forgot about the Crowhurst article, wonder if it is online now?
 
OP
mhardy6647

mhardy6647

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Thread Starter #5
Norman Crowhurst also published his version. Half the article was bitching about how well it worked but that no-one seemed interested in commercializing it.
hmm... I'll have to seek that out. Shouldn't be too hard to find...
 
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mhardy6647

mhardy6647

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Thread Starter #6
I once worked for a company that had... a long gestation time for their first successful commercial product (i.e., approved drug).
We used to say our motto was:
Bringing you yesterday's products, tomorrow.
 
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mhardy6647

mhardy6647

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Thread Starter #7
so, from that same issue, I just noticed this... which seems oddly appropriate to another thread here. :)
1613861126106.png
 
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