HDHomeRun 4 Review
As you know, I'm a huge fan of the SiliconDust HDHomeRun. I own probably a dozen of them, I love how they work and whatnot, and SiliconDust is the sole sponsor of RabbitEars (if you don't count free hosting by SatelliteGuys as "sponsorship"). SiliconDust recently released a new model of their HDHomeRun product, the HDHR4-US. I ordered one right away and got it a few days ago.
It looks a lot like the HDHR3, so I don't need to include pictures, I don't think. The functionality is basically identical to the HDHR3, and the HDHR2 for that matter. The real difference in the two is the tuner chip. And I'm pleased to report that the HDHR4 has a significantly improved tuner as compared with the HDHR2. (The HDHR3 had the same tuner as the HDHR2, to the best of my knowledge.) It is very obvious to me which stations have multipath, as those are the ones that suddenly are much more stable, or show significant improvement. I've made a table at the link below.
Red indicates an unwatchable or undecodable station. Yellow indicates a signal that is mostly usable but with dropouts.
|Ch||Callsign||HDHR2 (SS/SQ)||HDHR4 (SS/SQ)||Notes|
|7||WJLA||97 / 0-64||100 / 61-68|
|8||WMDO-LD||76 / 45||92 / 49|
|9||WUSA||100 / 82-92||100 / 98|
|11||WBAL||97 / 75-97||100 / 90|
|12||WWPX-LD||71 / 0||83 / 42|
|13||WJZ||95 / 75-83||100 / 81|
|14||WWTD-LD||82 / 73-86||95 / 90|
|15||WFDC||100 / 100||100 / 98|
|23||WDDN-LD||80 / 0||85 / 0|
|24||WNVC||100 / 100||100 / 98|
|25||WZDC-CD||81 / 79||82 / 77|
|27||WETA||87 / 77||89 / 85|
|29||WMPB||51 / 0||54 / 42|
|30||WNVT||95 / 75-95||95 / 90|
|33||WHUT||92 / 100||100 / 100|
|34||WPXW||100 / 100||100 / 98|
|35||WDCA||100 / 73-96||100 / 98|
|36||WTTG||100 / 79-100||100 / 98|
|38||WMAR||83 / 0-65||83 / 67|
|40||WNUV||91 / 86-100||94 / 90|
|41||WUTB||53 / 42||57 / 43|
|42||WMPT||92 / 100||94 / 85|
|44||WIAV-LD||83 / 76||85 / 72|
|46||WBFF||95 / 100||100 / 98|
|48||WRC||98 / 83-96||100 / 90|
|50||WDCW||96 / 84-100||100 / 98|
Please note, I took these measurements this morning, having played with the tuner before-hand a bit.
Now, a few things jump out at me:
First of all, the obvious one, is that a lot of the "bouncy" signal levels, indicated by a range of signal quality numbers, are now stable. This suggests to me significantly improved multipath handling.
Second, I believe the signal strength calculation has been changed. This is most evident on VHF, but it looks different on UHF as well, as many signals have clearly gone up. I haven't ruled out a better quality cable from the splitter on the newer tuner, but they're identical cables, so I can't imagine there being that much difference. Considering some of the multipathed signals seem to be relatively consistent, it doesn't look to me like they necessarily changed the 0 dBmV threshold that is 100%, but rather, made some change to how that is being measured. I will investigate with my spectrum analyzer at a later date.
Third, I believe the signal quality calculation has also been changed. I used to have many signals that maxed out at a solid 100%. Those signals, except for WHUT, now max out at 98%. The old tuners had 100% at about 32 dB MER, but modern transmitters regularly put out 36 dB or more. It also appears to me that the new tuner has a lower threshold to showing signal quality. Note how WWPX-LD and WMPB both show quality (albeit without decoding) on the new tuner but not the old one. I would also point out that WUTB showed broken PSIP on the old one, but not on the new one, despite the signal quality being one point higher on the new one. The threshold for clean decoding seems to be very similar, however; on either tuner, WMDO-LD breaks up significantly at 48, but is pretty solid at 52.
More analysis is needed, but I feel very confident that the HDHR4 clearly outperforms the HDHR2. Please let me know if you have any questions or comments.