Little Things: HDMI Repeaters for Long HDMI Cables

Since most audiophiles don’t believe expensive audio cables make a difference, why should expensive HDMI cables make a difference?

It turns out that cheap HDMI cables, even short ones, can produce sparkles or white horizontal lines flashing on the high def display.

This happened to me. My projector is in the back of the room, and my SSP is in the front. I have to run the HDMI cable 30 feet along the floor, wall, and ceiling, to reach the projector.

I pieced several cables together so that I wouldn’t have a long section of cable left over. Piecing several HDMI digital cables together is just asking for trouble.

As a result, I noticed a white line flashing at the top of the image on the projection screen. I knew immediately what it was and set out to cure the problem.

I Googled HDMI Repeaters and found many that are available. I found several on Amazon, and here is a photo of the one I selected.

This one is called the ELEGIANT HDMI Repeater, and it costs $12.95

Here is the link. (As this article passes time, the link will undoubtedly disappear, but if you Google HDMI repeaters, you will find others to choose from.)

Now, this is called a passive repeater. It has a small transformer inside that increases the voltage (5 volts is the standard in HDMI cable transmission).

At your SSP’s HDMI output, the voltage is 5, but if the cable is long or not very well constructed, the voltage will drop. The repeater increases the voltage so that it is about 5 volts when it reaches the display.

You will need one additional short HDMI cable. Plug one end into the input jack of the repeater and plug your existing HDMI cable into the output. It’s important to do this at the SSP end rather than at the display end. That is because the cable will pick up noise along the way, and if you use the repeater close to the display, the repeater will be amplifiying the noise along with the signal. The shorter the cable from your SSP to the repeater, the better. I used a 3 foot HDMI cable.

If you have a really long HDMI cable, then try an active repeater. This type has a wall wart to bring the power up to 5 volts.

Here is one I found on Amazon.

It’s called the Portta PETRT, and here is the link. It costs $17.88, but you will need to also purchase a 5 volt wall wart power supply. With this unit, you can adjust the amount of amplfication using the dial on the right side of the chassis. If I were installing a new home theater with HDMI splitters to send video to several rooms, I would definitely use something like the Portta PETRT.

The results are definitely visible. The images on the screen have no sparkles, and the white line that was flashing on my projector image disappeared.

It’s a cheap fix for a common problem. Try it if your display suffers from those sparkles or white lines.