Hi all.. Another Tech tip.. or at least a tech introduction
Have you ever wondered how the cable companies, hotels, dorms ..etc.. have their own television channels that don’t match the over the air channels? How are they doing it? How are they broadcasting analog when we are digital now?
Modulator banks. We will be looking at the blond tongue type… I know this isn’t really a tip its more of a exploration of the technology. From the modulator banks the feeds go into a signal combiner. We will focus on the modulator bank for now. Each of the channels you want you can purchase from blond tongue or on ebay. They come on modulator blades that look like this.
This one is tuned to Channel 54. You Order them pre-tuned to the channel you want. There are pots to bring the volume up and video color correction. There is also a Pot to fine tune the analog channel. (Pots are variable resistors. Your Volume up and Down is an example of variable resistance. A light dimmer is a Pot.)
Here are the hookups.. [Video In on top, Audio Left, Power, Audio right, RF Output]
Full Length of the Blade.. Time to put input into this Modulator Blade. For input I am going to use a digital over the air converter box. All of this equipment is meant to be mounted to a rack.. Like a server rack. There are instances where you will use cable boxes or satellite boxes. They will look like home units but will have commercial features. Anyway back to our input.. Over the Air Digital Broadcast Converter Box
Going to set it to a digital channel 11.2 and we will hook it to our Modulator Blade that is tuned to analog channel 54.
Now Lets Tune it in…
Little Static and perfect.. ME TV .. ah mash.. crappy show.. hehe.. anyways..
We have done it.. Now I am wired directly into the Modulator Blade. There is a Signal Combiner. It is basically a spliter with 12 inputs and one output. I have one here..
The Port on the front is to Check the channels.. When these are in a rack it is hard to get to the back of them. So its nice that there is a port on it.
You Plug your outputs from the Blade Modulators into the back of this guy and it combines it with little signal loss. I don’t have the next part. that is in the mix.. The signal amp. You really don’t need it if its close so I never acquired one. Pretty neat technology. Thanks for checking it out. If you have any questions about video technology hit me up. I am still learning. I think its neat..