Question:
"I need help hooking up my TV to digital cable, DVD and VCR. I have a RF modulator, but no instructions. My TV is an older set with one cable hook up - the modulator has room for 4 hookups. Please, any help would be greatly appreciated."

HDMI Encoder Modulator,16in1 Digital Headend, HD RF Modulator at SOUKA https://www.soukacatv.com/.

Answer:
This is a problem a lot of people have - with or without a RF modulator. In this case, we'll attack the problem with the RF modulator in mind. After you connect everything you'll notice working with a RF modulator is just like working without one, except those with a RF modulator will have one device between their video signal and television.

As for the instructions, I am going to assume the DVD player is not a combo unit with the VCR, and that you want to record TV on your VCR. Step 4 will include connecting your DVD player, but if the DVD player is a combo unit with the VCR, just ignore Step 4 as DVD connection will be included in the VCR set up.

Step 1: Connect the coaxial cable coming out from the wall to your digital cable box in the ‘video in’ slot. It might also be labeled ‘antenna in’ or ‘cable in’.

Step 2: From the cable box, connect a coaxial or composite (yellow video cable) and stereo (red-white) RCA audio cables to the VIDEO IN terminal on your VCR.

Step 3: From the VCR, you will have to connect this to the RF Modulator using a coaxial cable from the VIDEO OUT on the VCR to one of the IN ports on your RF modulator.

Step 4: You can now connect your DVD player to the RF Modulator by using the yellow-red-white composite/RCA cables from the VIDEO OUT on the DVD player to another port on the RF modulator.

Step 5: From the RF modulator, connect this unit to your TV by using a coaxial cable. It will be from the VIDEO OUT on the RF modulator to the VIDEO IN or CABLE or ANTENNA IN port on your television.

This should be all you need to get started watching your digital television. In simple terms here is what you did:
Coaxial from wall to cable box
Cable box to VCR
VCR to RF modulator
DVD player to RF Modulator
RF modulator to TV

You will only be able to record what is on channel three because the digital cable will require you be on channel three. As for future connections to the RF modulator - just plug your viewing device into it and hit the button activating the video signal for the device you want to view. As long as it is connected to the television and the TV is on channel three, you should be able to see your video signal.

Established in 2000, the Soukacatv.com (DSW) main products are modulators both in digital and analog modulators, amplifier and combiner. We are the leading communication supplier in manufacturing the headend system in China. Our 16 in 1 and 24 in 1 now are the most popular products all over the world. For more, please access to https://www.soukacatv.com.

Source: https://www.lifewire.com/connect-digital-cable-to-tv-3974918