Amplifier help

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fadinho89

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Does LM741 amplifies the signal from a source which is a mic? can give a simple circuit? Perhaps a link from a website will do? thanks!
 
The 741 is an op amp and can be substituted by other op amps without much trouble. For example, this link shows a typical circuit, and to make it complete, you have to look up the Data Sheet for the op amp you want to use and find the pin numbers for the 5 connections to the op amp.

**broken link removed**

Here is another example:



Here is another link:
**broken link removed**
 
Sorry but it's a silly idea to use a 741 because it's a rubbish op-amp IC.

Use a real op-amp like the TL071.
 
The lousy old 741 opamp is 40 years old this year. It was not designed for audio because it is too noisy and its full output frequency response goes up to only 9kHz.

A TL07x opamp is low noise, inexpensive and has a full output frequency response to 100kHz.
 
Can you suggest OPAMPs for distributing composite video (dc to 6MHz) and drive 70mA or more. Some OPAMPS I could locate. But difficult to get.
 
Many years ago I made video distribution amplifiers. I used video amp ICs, not opamps.
 
Most semiconductor manufacturers have video amp ICs.

True. But one problem is that if I choose something like that, it may not be available in the market. Buying less than 10 Nos otherwise is too expensive. So I thought you may be suggesting something which is popular and may be available in market (I am looking for DIP Package).
can you just tell me which IC you used?
 
I made my video amps about 16 years ago. The ICs were made by Motorola. They aren't made anymore. The ICs were inexpensive.
I don't know what is available in your country. Ask somebody in your country.
 
I made my video amps about 16 years ago. The ICs were made by Motorola. They aren't made anymore. The ICs were inexpensive.
I don't know what is available in your country. Ask somebody in your country.

I think, nowadays what is commonly available there will be like that here also. Right?
 
You can use an op-amp, check out the National and Linear semiconductor sites for op-amps that have enough bandwidth and drive.
 
Video ICs are usually triple (R,G and B) and can drive 150 ohms (75 ohms sending then 75 ohms receiving.
Opamps are usually dual or quad and drive 2k ohms.
Video ICs usually have the gain setting resistors built-in.
 
Not that I've seen. I can get parts from several sources, digikey has almost everything. Does India have a digikey equivalent?

Yes. One is RS components India. But problem is that price is 5 to 15 times the open market price for small quantities less than 10 (including their postage charge). Is the case with Digikey different?
 
Video ICs are usually triple (R,G and B) and can drive 150 ohms (75 ohms sending then 75 ohms receiving.
Opamps are usually dual or quad and drive 2k ohms.
Video ICs usually have the gain setting resistors built-in.

Here I don't need RGB output. Only buffering of composite video required. I think, I can use OPAMPs with higher current drive capacity to drive many 75Ω loads. Many are available, but the availability in the electronics market here to be checked.
 
Here I don't need RGB output.
Since most users of video amps have historically been using RGB, that's the most common (and therefore most available and usually cheapest) product.
 
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