HI -- I WROTE THIS REBUTTAL TO GOOD OL' JB BUT I DID NOT SEND IT AND
PROBABLY WON'T - BUT WONDER IF IT MAKES SENSE AND IF NOT, WHY NOT...
HE JUST BURNS ME UP WHEN HE BLOWS ME OFF BY SAYING I AM IGNORANT... THAT
IS NOT AN ARGUMENT, IT IS JUST NAME CALLING...
OHHHHH..... HE BURNS ME UP...
ANY REASON THIS LOGIC IS WRONG?
Note - Again I did not send it and probably won't
but I am sick and tired of his being a bully instead
of a teacher.
-- JHR --
----------------------------------------------------------
DRAFT DRAFT DRAFT DRAFT
------------------------------------------------------------
On 1/17/2014 4:43 PM, Jim Brown wrote:
No, there is a gap in your knowledge of fundamental electricity and
electronics.
OK... once again, you tell me I am ignorant, rather
than explaining it. One does not need an
engineering degree to get this.
FACT - switch mode supplies are often noisy. In fact,
the new Chinese supplies have a knob to "shift" the
noise when it adversely affects the operating frequency.
You can debate whether or not that is "good engineering"
practice, but there it is.
FACT - linear supplies seem inherently less problematic,
and don't seem to have these extra noise controls.
FACT - historically, when switch mode supplies first
arrived on the scene, there were many complaints about
excessive noise - certainly more or different types of
complaints than hams were expressing about linear supplies.
If switch mode supplies were not inherently noisy, there
would be no discussion about whether or not "good
engineering practice" has sufficiently masked, suppressed
or fixed them to make them useful in the shack.
Your spin makes it sound like there is no issue or
problem at all, and I don't accept that.
No, we simply follow good engineering practice when designing and
manufacturing the product in question.
OK... I guess what you call "good engineering practice,"
- I call masking and suppressing noise. Manufactures
have "improved" them over time, but I do not believe
they have done a complete job of it.
FACT - Ten Tec sells switch mode supplies it concedes
make noise outside the ham bands - rendering them
useless when using their own general coverage receivers.
This does not happen with a linear supply.
So, you can call me ignorant...again... and smother me
with a vitae of advanced degrees...but the fact is,
I prefer linear supplies because they seem to be
inherently less problematic, much quieter and do not
produce the same noise my TenTec switch mode supply does.
Paul Clinton admits switch mode supplies are noisy,
but TT does not care, because they don't make noise in
the ham bands. Apparently they are not intended to
work with their general coverage receivers and other
radios.
Enough with dumb analogies. Go to the ARRL Handbook and study the
fundamentals.
I read that, and it sounds like switch mode supplies make
noise that "good engineering pracitce" is supposed to
mask or suppress. But, calling me names does not
provide an explanation... It takes logic, science, and
a little patience to accomplish that.
The discussion is based on the fact that switching
mode supplies are inherently noisy - or at least more
noisy than linear supplies. It did not just arise
out of nothing.
Anyone wanna buy my Ten-Tec switch mode power supply ??
__________________________ JHR ________________________________
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|