Product Catalog

Pro AV Catalog

Contemporary Research

4355 Excel Pkwy
Suite 600
Addison, TX 75001
United States
Project List
Can I use my HDTV modulator’s HDMI input?
Posted on Tuesday, May 20, 2014
The answer is yes, with provisions. HDMI is a fine format, but problems arise with HDCP.

When HDCP was developed by Intel and others, and the general idea was fine – prevent unauthorized distribution of HDCP-encrypted content. However, the way it’s implemented, it also blocks you from distributing your own non-proprietary content, such as digital signage and other media. They didn’t think about that, so you’ll need to work a bit to show your own content.

Those of us who feature HDMI inputs on our digital QAM modulators can’t accept HDCP-protected content, as we are broadcasting clear QAM channels that can be tuned by any HDTV tuner. Twisted-pair video systems pass on HDCP protection (and its issues), but fool the source into thinking it’s feeding only one TV. A reasonable trade-off, but at great expense to protect content that is largely not proprietary anyhow.

The whole idea is somewhat moot, as technology has arisen with a master key that allows protected content to flow freely. So those who are using content in illegitimate ways can continue to do so, while honest folks can’t even see their own stuff. As Edward Felten put it, “The main practical effect of HDCP has been to create one more way in which your electronics could fail to work properly with your TV.”

So yes, because of HDCP, your HDMI connection can be iffy for any kind of content, but there are solutions.

Kramer PT-1C
This new widget from Kramer can absolve a multitude of sins, including HDCP, EDID, Deep Color, and Dolby.

There’s a 4-position switch that activates the fixes:
  • EDID passes through or locks EDID, it also seems to fix EDID issues in both modes
  • Deep Color – turn on to select 8-bit color. Not an issue with QMOD technology
  • Audio – changes audio to LPCM stereo – a nice fix for devices that don’t support AC-3, again, not an issue with our new QMODs
  • HDCP – turns it off so you can broadcast your own media
  • I enjoyed testing this device, which works very well, doesn’t need a power supply, tiny (about 2?x 3?x 1?), and retails for $165. This is the best option to cure your HDMI HDCP/EDID ills.

Kanex ATV Pro
This clever little device converts HDMI to RGBHV and stereo audio. Works great, doesn’t need power, handles EDID, and is very low cost. You’ll find similar dongles on Amazon that to pretty much the same thing, with or without audio. My guess is they all use the same chip.

A must-have accessory if you travel with an HDMI laptop and need to patch into someone’s analog VGA input.

It’s also a great solution to output digital signage to the QMOD-HDSC or QMOD-HDMI 1.5 VGA port (together with the Kramer, allows you to output 2 channels of signage with the HDMI 1.5)

Linux Signage Players
While Windows and Apple players have their HDCP issues, Linux-based players such a Brightsign do not. My guess is that, as a dedicated digital signage player, HDCP isn’t required. I’m not sure if other players have the same benefit – if one of our readers has experience with other units such as Key West, SpinetiX, and AM – give us your feedback. I also appreciate that Tightrope is now compatible with Brightsign players.

Other Open HDMI Sources
Other sources that do not have HDCP on the HDMI output are:
  • Our 232-ATSC+1 HDTV tuners
  • DirecTV receivers, especially if the site has a Public Viewing contract
  • SDI – to – HDMI adapters
close