27 Feb
2008
27 Feb
'08
5:28 p.m.
On 27 Feb 2008 at 22:57, Tony Duell wrote:
No _new_ components, but you still have to reprogram
the microcontroller
(which may involve pulling it from the board..). Personally, I'd rather
change some R's and C's
Some uCs have the ability to program in-circuit. But popping a 6- or
8-pin PIC or AVR uC out of its (machine pin) socket for reprogramming
is a simple enough task. I keep a pile of them at the ready and just
cycle through them when I'm tweaking things. Most have wide supply
voltage tolerances and good (i.e. 25 ma) drive capabilities.
Cheers,
Chuck
Yes, it might be fun doing it with NE567s or somesuch, but then,
someone even more conservative would castigate you for not using
tuned LC filters and discretes for the active part. A couple of
6SN7s and some powdered-iron core inductors should do the trick...
I have an _old_ modem where the reciver has an input filter consisting of
a metal can with 8 or so tuned pot cores and capacitors in it. The output
of that is mixed with a local oscillator, the 'sum' frreqeuncy is taken
and fed to a discrimiator circuit. All discrete transsitors, of course...
I really like the little microcontrollers--they're cheap and they do
the job. I'm not averse to using them when they're the best
solution.
So do I. The operative part being 'when they're the bast solution'. I
don't feel they are in this case.
-tony