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Level shifting
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syntax333:
Hi, the circuit that you suggested worked perfectly thanks for the suggestion. However, I got two issues, this could be due to my low knowledge about the buffer circuits.

1) You can see the output of the clamp circuit (indicated by White) + output of the buffer circuit ( indicated by Yellow). Output of the buffer seems to have degraded compared to output of the clamp circuit. Also there is no load connected to output of buffer at the moment.

Is this due to wrong chosen values of follower configuration parameters such as voltage and resistor values or something else?

The values that are chosen is shown in attachment.

2) I want to drive a 200mA load with this configuration. Probably due to wrong values of resistors and supplied voltage, resistors and transistors are heating up pretty quickly. The load is approximately 17.5-20 ohms.

How do I get rid of the heating problem? Should I buy high power resistors like 5W?  Or cooling down transistors with heat sink etc.

(NOTE: currently I am using BC327 and BC337 as bjts)
Benta:
I see several issues.
It looks as if you're clamping on sync, which is fine. But it's very obvious that your Vref is not able to deliver the current needed when clamping occurs. It needs to clamp a 75 ohm signal and is not able to do it, otherwise the sync tips wouldn't be angled, but horizontal.
You might be able to cure this by using a larger decoupling cap for Vref, if not you'll need to buffer Vref.

For the first emitter follower, I'd try using 1 kohm as emitter resistor, this will bring down power consumption and gain demand.
For the second, with a 100 ohm emitter resistor, you're burning around 0.6 W of power in the transistor and resistor (I'm assuming 12 V supply) and yes, this will get hot.

Let's know how you get on.
syntax333:
sync tips being angled is probably due to the ac coupling cap at input I changed the value with 10uF. However, this time there are spikes at certain times as shown in attachment.

I have changed the value of resistor on first follower with 1kohm. Besides that is there anything you can suggest for the heating problem?
Benta:
This is getting interesting. To move on, I have a few questions:

What exactly is your CVBS source? is it 1 Vpp, 75 ohms or something else?
Did you follow the LM1881 component recommendations 100%?
What is your Vref?
Is the input cap polarized correctly (positive side to the emitter followers)?
Have you decoupled everything correctly (mix of 10n and 100n caps?
Are the wires too long (everything should be close together)? If you're using a plug-in breadboard, I'll find you and kill you.   :)

The spikes are not important, we can take of them along the way. But what I see in your second trace is, that the CSOUT is only present on the second video line. So the LM1881 is not operating correctly.
I also see a level shift, so I suggest increasing the input cap to 47...100 uF

syntax333:
1) Yes I just checked again and it is exacly 74.4ohms and 2.76Vpp (is this normal?).
2) Well, I don't have the 680kohm resistor so I made it with using other resistor values parallel and series combination to get the desired value. Besides that everything is according to datasheet.
3) I give 6V as reference voltage. Also supply voltage to the lm1881.
4) Yeah it polarized correctly.
5) If you mean supply voltages and reference voltage yes I did.
6) Wires are not too long. Unfortunately, I am using breadboard while experimenting  :-[

I increased input cap to 100uf.

You are probably right about the lm1881 working not correctly as we can see from the attachment..

I will create a schematic of the circuit that I build and post here to make things clear.
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