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Old August 18th 03, 07:22 AM
Harry - SM0VPO
 
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My point was that the art of homebrewing loses something when it's reduced
to
just plugging in a chip. Seems like everyone is ignoring how the circuits

work
and taking the 'black-box' approach instead.


I can agree with you, but only up to a point, but do you never think that
"them there chips" can possibly be used as a tool? A component? A lot
depends upon where you draw that line between what you call homebrew and
black-box. Do you not think that an Operational Amplifier, like the UA741,
is a component? or would you rather use a slack-handfull of transistors
every time you need an Operational amplifier. I personally put the prescaler
chip in the same category as the OpAmp.


... where's the fun in just hooking up power to a chip? That's
not homebrewing, at least not in my book.


I get a great kick out of using CMOS and TTL chips. For example, one CD4007
can be used to build a complete superhet receiver. If I want a VHF
synthesiser then I have absolutely no hesitation to using a couple of CD4000
chips and a prescaler. Logic, to me, is also homebrew. As I said before, it
all depends upon where you draw the line.


Try a simple flip-flop. Two transistors, that's all. There are probably a

few
dozen schematics on the net and dozens more at the public library (you do

have
public libraries in Sweden, don't you?).


I didn't have to search for a circuit, but using simple transistors I have a
circuit that is stable, but only up to about 95MHz. Here in Sweden, the ONLY
non-power RF transistor I can find in Sweden is the 2N2369 (NPN) and it is
that transistor that has increased the operating freq. of my stage to 96MHz.
I have also tried just a simple schmitt trigger circuit and again, about
100MHz is the top limit for conventional transistors.

Anyway, I am still having fun on the workbench and I will continue to do so.
When I don't I will probably join all the others who are sick of radio and
homebrew and get on the Internet. Prabably even subscribe to a hamradio
newsgroup, such as "rec.radio.amateur.homebrew" and maybe even communicate
with othere without the QRM.

Best regards - Harry (SM0VPO)

(If it feels good - do it!)