Hi Zim,
To be fair to TI, their intention is that these amplifiers be used in
self-powered
speakers, where the speaker wire length is inches (sorry, cems) at worst.
For the last few weeks I've had a couple of these driving a pair of whacking
great JBLs in my office, and they sound better than they have any right to.
Big welly from something about the same size as an op-amp. Amazing.
Better yet, they've passed the headache test (long-term listening fatigue)
which many amplifiers haven't.
We're designing them into a product for someone now, which incidentally
- and highly relevant to your point - like any other commercial product
is going to have to pass Part 15 and CE emissions testing . . .
Anyway; I'll drag one outside and plonk it under the antenna and see what
happens.
Your local friendly LF pollutant,
Steve W3EEE
1/26/2002 8:46:32 AM, "Graeme Zimmer" <[email protected]> wrote:
Hi,
Those of you interested in digital transmitters might take a look at the
new(ish) TPA3000D1 from TI.
www.ti.com/sc/tpa3000d1
It's a class D audio amp capable of 17 Watts audio. It has a switching speed
around 200 Khz.
I figure it's a "good news" and "bad news" story.
The good news is that it could possibly be used as a basis for a simple qrp
VLF TX
(I figure that the RC osc could be over-driven by an Xtal osc...)
The bad news is that they are seriously proposing that these things be used
in consumer equipment without any form of output filter....
......................... Zim
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