Quote:
Originally Posted by jeyurkon
I considered something similar. But 20MHZ seemed too close to 24MHZ since you're looking at over a 3MHZ bandwidth for the TV and it seemed like the 20MHZ would be difficult to filter out and still achieve a flat response. So I was thinking about upverting it before down converting it. Adding another step.
If I understand the 415 circuitry correctly, you wouldn't have to do much to the post injection if you do the shift from 44 to 24 accurately.
John
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Interesting point! I'm pretty "rusty" at circuit design in general, and even more so with Solid State and PC Board design work specifically. My last design project used tubes and a hand-wired chassis and that's been a few years ago. Last time I designed anything with a Transistor or IC was nearly 10 years ago, and just a simple Audio device built on a pre-fabbed prototype PC board. Last time I actually etched a board from a published template was over 10 years ago. It's been even longer than that since I designed anything from scratch all the way to board layout and etching. Back before the Net existed and when CAD software and a suitable PC still cost as much as a new car. Back then, photocopying hand-drawn artwork onto special transparency stock sold under a trade name of "Tech 200" and using that like an "iron-on" transfer to get the mask onto a copper-clad board blank was the only way to economically do any kind of one-shot photo-etching. The "Tech 200" stuff also worked nicely with a printed Template from a magazine article provided any flaws in the Original were touched up before making the transfer on the "Tech 200" stock. Basically, the toner deposited on the "Tech 200" would "transfer" (like an iron-on decal to a t-shirt) to a copper-clad board when heated
properly with an ordinary iron (or make a serious mess, ruining the "Tech 200" sheet and virtually wrecking the board blank if
not heated evenly).