Re: Is S.E.D actually sci.electronics.DUMMIES ??

Jim Thompson wrote:

Where are all the gurus when you want a real engineering
answer? Sucking on their thumbs and bowing to Gore ?:-)

Some of us have had real work to do these last few days,
I for example spent all day Saturday, in an exhausting
stint solving a vexing sp/dif interface problem, and all
day Sunday trying to rebuild my wife's computer, now 80%
done. Today I helped a fellow who wants 1kV at 38MHz,
and struggled with bringing up more of my batch of eight
handbuilt 400MHz DDS boards.

Also, frankly, not all of us enjoy talking to you, when
you regularly insult us with your threatening daydream
posts, re what should happen to the majority who can't
stand GW Bush, or his cronies, or their policies.

I imagine you find the preamp, although functional, a
poor example of streamlined design. Yes, sure, it falls
down on many counts when evaluated as to what it might
have been. (Working from memory now because my time is
short: I'm supposed to be home.) I previously mentioned
the appeal of current sources and optionally a mirror.
Futher along the path, if the currents from the beefed-up
input-pair had been sent directly to the output amplifier,
four parts, including two ugly electrolytics, could have
been eliminated. In addition the gain equation would
look cleaner. The electrolytic in the input emitter pair
is especially ugly. One reason is its time constant is
hugely affected by the choice of gain, pushing up toward
the minute region at low gains, IIRC. That's awkward at
power-up, and makes second-stage ac coupling mandatory.
Better to remove all three and implement the high-pass
differently. I'd consider a different variable-gain
scheme. Proper feedback to the input-pair emitters
would be appealing. There's more, but that's a start.

Yes, certainly the circuit could be improved, but that
doesn't make it crap.

.

Relevant Pages

  • Re: Is S.E.D actually sci.electronics.DUMMIES ??
    ... four parts, including two ugly electrolytics, could have ... In addition the gain equation would ... The electrolytic in the input emitter pair ... Not to say that compound devices aren't useful... ...
    (sci.electronics.design)
  • Re: Is S.E.D actually sci.electronics.DUMMIES ??
    ... four parts, including two ugly electrolytics, could have ... In addition the gain equation would ... The electrolytic in the input emitter pair ... Proper feedback to the input-pair emitters ...
    (sci.electronics.design)
  • Re: Is S.E.D actually sci.electronics.DUMMIES ??
    ... Where are all the gurus when you want a real engineering ... In addition the gain equation would ... of the circuit in order to remove it. ... I (and many other audio designers) have done that too. ...
    (sci.electronics.design)
  • Re: Is S.E.D actually sci.electronics.DUMMIES ??
    ... Where are all the gurus when you want a real engineering ... In addition the gain equation would ... they dont seem anymore reliable with no dc bias either. ... but I expect the audiphiles wouldnt like this due to the extra noise it ...
    (sci.electronics.design)
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