Results 1 to 3 of 3

Thread: SiliconDust HDHomerun network-attached ATSC DTV tuners

  1. #1
    Join Date
    Jul 2005
    Location
    Springfield, Missouri
    Posts
    1,009

    Default SiliconDust HDHomerun network-attached ATSC DTV tuners

    I've been doing some research on the latest model HDHomerun tuner devices. I've been curious to see if SiliconDust engineers are bringing their models up to any type of tuner standards that the Zenith/Insignia DTT900/901 converter boxes had, with their MaxLinear tuners.

    This information is a little dated, (January 2013), but MaxLinear had published a News Release about their tuner chip (MxL603) being selected for the next generation of SiliconDust HDHomerun tuners, which should include the current models of the HDHomerun4-US tuner. This is the same TV tuner everyone in the television industry has been bragging about what makes a new ATSC television so great. Many dxers that have recently bought new LG Electronics televisions have found their TV's decode and hold signals much better than the Zenith or Insignia converter boxes. Those were manufactured in 2008 and of course, the MxL603 tuner chip is a 2013 product.

    http://www.maxlinear.com/silicondust...uner-products/

    In MaxLinear's documentation, they state the MxL603 has an exceptional noise figure (NF) of 3.8 decibels. The industry standard for the NF of an LNA (low noise amplifier) in the tuner front end is in the range of 2.4 dB to 3.5 dB. For a better understanding on the development of LNA's for TV tuner applications, you can browse this article...

    http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf

    I have a inquiry ticket open at the SiliconDust tech support center for inquiries about the tuner chip and board in the latest models of HDHomerun. I would greatly appreciate feedback from any DTV dxers that are using NEW models for their dxing. I currently use a HDHomerun Dual ATSC Tuner, which is a 2011 model.

    ***I promptly received an answer to my inquiry ticket just today--

    "Confirming, the HDHR4-2US uses MaxLinear MxL603 silicon tuners.

    The HDHR4-2US includes a LNA and RF splitter inside to feed the two tuners. When testing/comparing performance note that too much external
    amplification can degrade reception. Single-tuner devices like TVs tend to have higher max-signal headroom as they don't require an amplified splitter inside.

    Nick

    Nick Kelsey - CTO
    Silicondust USA Inc."
    Last edited by Jim Thomas; 11-28-2016 at 10:44 AM.
    Jim Thomas
    Springfield, MO

    Ozark Mountain DTV dxing Daredevil

    Dx Equipment - AntennaCraft MXU59 UHF antenna & homebrew version of AntennaCraft Y10-7-13 VHF antenna @ 25'. Both antennas fed through a Winegard HDP-269 12dB pre-amp; a Zenith DTT901 converter box & a Silicon Dust HDHomerun Dual ATSC tuner, using Rabbitears autologger support.

  2. #2
    Join Date
    Jul 2005
    Location
    Pleasant View, TN EM66
    Posts
    4,403

    Default

    Nick has a very good point.

    Amplifier overload can cause compression and symbol loss. It doesn't take much symbol loss to prevent reception of one or more channels.

    I advise viewers to *not* use amplified antennas in Davidson County, where the transmitters are. Usually, rabbit ears will work better.
    Doug Smith W9WI
    Pleasant View, TN EM66
    http://www.w9wi.com

  3. #3
    Join Date
    Jul 2005
    Location
    Springfield, Missouri
    Posts
    1,009

    Default

    I received a follow up email from Nick Kelsey with SiliconDust - "The LNA used in the HDHR4-2US has a 1.3dB NF so the NF of the MxL603 doesn't come into play."

    According to the numbers I quoted earlier of 2.4 dB to 3.5 dB NF for the LNA, this means the HDHomerun4-2US actually has a very low NF, compared to the acceptable industry standards. The dB quoted above for the MxL603 would then be just for the tuner, NOT the LNA.
    Last edited by Jim Thomas; 11-28-2016 at 07:56 PM.
    Jim Thomas
    Springfield, MO

    Ozark Mountain DTV dxing Daredevil

    Dx Equipment - AntennaCraft MXU59 UHF antenna & homebrew version of AntennaCraft Y10-7-13 VHF antenna @ 25'. Both antennas fed through a Winegard HDP-269 12dB pre-amp; a Zenith DTT901 converter box & a Silicon Dust HDHomerun Dual ATSC tuner, using Rabbitears autologger support.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •