Re: OSC and unity gain buffer


eeaj2002 wrote:

On Apr 10, 9:57 am, "Joel Koltner" <zapwireDASHgro...@xxxxxxxxx>
wrote:
"Tim Wescott" <t...@xxxxxxxxxxxxxxxx> wrote in message

news:6rydnbZMeMTA2WPanZ2dnUVZ_g2dnZ2d@xxxxxxxxxxxxxxx

The design philosophy of an op-amp is that you use a crappy amplifier with
tons of excess gain, and fix all of the amplifier problems with tons of
feedback.

And here I was about to give you $100k to build me a class A, zero-feedback,
tube-based audio amplifier because it will OBVIOUSLY sound so much better than
a traditional design with your approach. :-)

Thank you all for your help. I need further help please.
I wrote a simple program that generate a monochrome NTSC signal. I
connected this signal to one of the eye glasses which take the NTSC
signal but nothing was displayed. When I connected my signal to the
DVD player and I fed the output of DVD player into the eye glasses
then it displayed fine. I am assuming the reason for not displaying
is the color burst that is missing (When I compared my signal and the
output of the DVD player signal, the color burst was missing). This
why I was trying to see if I can sum the 3.472MHz signal with my NTSC
signal and see if I can display my signal on the eye glasses. By the
way the eye glasses have VGA color display that takes the NTSC or PAL
signal.

Thank you all,

John.



First thing is that you don't want a unity gain buffer. You want a
gain of 2, with a 75 ohm resistor in series with the amp's output and
the coax. The 75 ohm termination at the other end will divide the signal
in half, back to the proper level. Without the extra gain and resistor
you have a sever mismatch which causes no end of problems.

You also want to make sure the cable is 75 ohms if it's more than a
couple feet.



--
aioe.org is home to cowards and terrorists

Add this line to your news proxy nfilter.dat file
* drop Path:*aioe.org!not-for-mail to drop all aioe.org traffic.

http://improve-usenet.org/index.html


Use any search engine other than Google till they stop polluting USENET
with porn and junk commercial SPAM
.

Quantcast