Review on Voca Tech Digital ISDB T Modulator by Daniel Casper

Voca Tech's HDMI MPEG-2 ATSC/DVB Modulator is a device that accepts HDMI video/audio and converts it into an ATSC/DVB modulated signal converts. This is not an easy task as it requires MPEG2 compression, PSIP table building and advanced 8-level digital modulation. Transmitter units cost tens of thousands of dollars. Hotels and bars can easily spend $3,000 to create an HD home channel. So what do you get with a box of Voca Tech for less than $500? This is a combination of good and mediocre qualities. It outputs a crisp, high-definition television signal that most, but not all, receivers can pick up. .Testing a set of 10 I found the following results: 8 sets picked up the modulator with no problems. One had excessive lip sync error compared to the others but was otherwise fine. You could only see a gray screen with channel numbers and program names. Note. Granted, the two that struggled were cheap and unbranded. From this I conclude that you will get the best results with a major TV label. The included instruction manual was marginal at best. The illustrations were barely visible with little explanation of the settings. This product is high tech. The user must at least understand how to set a static IP address on their computer. It also helps to have some understanding of MPEG encoding. I tried to include readable screenshots of the settings that worked for us, but unfortunately they got messed up after posting for this review. We hope that the comments highlighted in red will help you. You are free to experiment with the GOP (I-frame/P-frame group of pictures) setting. GOP 16 through 32 seemed the best, but expect a slight strobe on all settings. The delay (adjusting audio delay when lip syncing) is fully adjustable and works best for us at 700ms. The main and sub channel settings are just a fake PSIP channel number displayed on the TV and have nothing to do with the real modulated RF channel. You can set them to any channel you want. The program name is the name of the channel that is displayed along with the PSIP channel. The true modulated frequency should be set to the center frequency of the broadcast channel. Use the attached table to set the output channel. Minimize coax loss by using a VHF channel such as B. Select 7. Notes: No LCD display and no adjustment buttons. All settings are made via web management. The default login is 192.168.0.136 admin admin. Be very careful when setting the password and IP address. After losing it, you may need to ask an IT professional to help you get it back. Unless you're a techie, consider leaving them alone. The fan is strong. I recommend placing the unit in a ventilated closet or basement. Sound - PCM stereo. As far as we can tell, AC3 isn't supported. If you don't have audio, make sure you send it to stereo PCM. Sound gain is not adjustable and tends to increase. You can observe clipping on loud source material. Note: We are powered by Dish Network Joey's HDMI output. When we turned off the receiver's AUDIO LEVELING Dish, the sound became quite satisfactory. While Joey's audio worked, the Hopper HDMI had no audio until we connected stereo PCM to the HDMI cable. This required an embed block from J-Tech. The RF output level is low compared to commercial head modulators. Start with a setting of -20 dBm. This model will NOT encode the QAM used by CATV and the description never said it could. It will modulate the normal ATSC 8VSB broadcast. Cable TV boosters don't work either. Keep this in mind when attempting to mix these two images for the same TV. The MPEG2 encoder is not a great performer and shows very little strobing on fast-moving screens. Not the best for the sport. I would call it a lower frame rate. To save the settings, you must click on "APPLY" and then on "CONFIGURATION" > "SAVE". The company's technical representative was very responsive and willing to answer my questions and help me resolve a technical issue. Please note that they use Skype messaging and operate out of China. This box is sold under different brands so you can find more videos and setup guides online. As such, I find the video quality acceptable for my needs and would buy it again for home use for viewing on multiple TVs. A small hotel, college or church might use this for internal channel and visitor information. Ideal for surveillance cameras around the house on multiple TVs. At the moment I don't recommend this device for dynamic videos like a sports bar. In fact, you can expect some video quirks from a product sold for a fraction of what high definition modulators are on the market. HDMI distribution may be the best choice for a high-quality single-channel system, but it's an acceptable option for a multi-channel system. I like it and am planning to buy another one for distributing satellite TV at home.