rom@xor.Sun.COM (Achyutram Bhamidipaty) (07/09/89)
HELP! I need some help in implementing a buffer for a video source. I have tried using a LM733 but this simple chip has proved too complicated for me to use! The video source has a Vp-p of approx 1v. I would like to have the buffered signal have a Vp-p of approx. 4-5v. Does anyone have ANY ideas??? Part of my problem seems to be that the minimum gain of the LM733 is 10, another problem is that I dont know what the source impedance of my video source is. I tried using a voltage divider to drive the '733 but I couldnt get that to work and I really dont know why it wouldnt! I do have two +5v supplies, and in the configuration I tried I had the '733 powered at +/- 5v, is this the right way to go? Should I be using a different amp? Please help!!!! I spent 4 1/2 years in college learning how to be an engineer, and when I got out I thought that I was pretty smart. Boy do I feel dumb now!! Thanks for any help. -Rom rom@xor.sun.com -Rom rom@xor.sun.com
mmm@cup.portal.com (Mark Robert Thorson) (07/11/89)
The May 1987 issue of Radio-Electronics has an excellent article on the use of the Signetics NE5205 as a video amp. This chip is essentially a
mmm@cup.portal.com (Mark Robert Thorson) (07/11/89)
I accidently sent the previous message to the net instead of the editor server node. What I was going to correct was the statement that the NE5205 was being used as a video amp. It was being used as an amplivier for a broadcast TV signal. It is a wideband amplifier with four connections: power, ground, input, and output. Much simpler than a 733. (Isn't that a dual 741? Barf city. Use an LM324 if you need a good cheap op amp.) Although the NE5205 is intended for frequencies two orders of magnitude higher than video, it might be a good solution for soemone who needs a simple circuit There might be a similar part for video work.