HDHomeRun Flex 4K video issue with good signal

Channels DVR Server
#1

I have the following setup:

Mac Mini M1 16GB memory running MacOS Sonoma 14.4 with 2TB SSD Hard Drive
Channels DVR Server
HD HomeRun Model HDFX-4K FW: 20231214
Silicon Dust LTE Filter
GE UltraPro Outdoor 4K 1080P HD Antenna

The Flex is connected to the Mac Mini Channels via a Ubiquiti UDM Router 1GB connection.

When I display the SignalGH signal strength/quality for NBC channel 11.1 in the bay area I get 100/100 respectively.

However I still get regular video freezing/dropout on either a live or recorded broadcast.
I also get it using HDHomeRun app doing a live stream directly to the HDHomeRun Flex.

Suggestions?

#2

Honestly, a 100% signal strength is most likely a bad thing in your case. HDHR tuners are notoriously susceptible to overpowered signals, which result in poor video.

I would recommend you put an attenuator (or a splitter with one end capped) between your antenna and the tuner. (Or if you are using an amp of any sort, remove that from the line.) You will most likely notice a marked improvement.

1 Like
#3

I don't have any amps. Are you saying that the SiliconDust LPF-608M LTE Filter does not do any attenuation and I should add something like the splitter you suggested?

What kind of signal strength should I aim for in the SignalGH app?

#4

As far as I am aware, it is merely a filter, not an attenuator.

Personally, I would aim for something between 80-95. But my personal experience with SD's HDHR tuners over the past decade or so says if the signal strength is 100%, you will have problems.

While generally great, there are 2 major flaws with SD's tuners:

  1. They are far more sensitive to over powered signals and fail too easily, and
  2. Their power supplies are horribly unreliable, requiring frequent replacements.

(From my personal experiences: to the first I inserted myriad splitters to get the signal strength just right to get a picture but not blow out the tuner; to the second I have bought many power supplies online over the years to keep HDHR tuners going.)

#5

I just had to go through this again last week. My signal was already attenuated but my OTA signal started freezing and sometimes I would get audio pops. This only happened at night. I had to add an additional 6dB of attenuation to my signal for a total of 19db. Basically i just kept adding 3dB attenuators until i got my signal in the 85-90% range. I found the signal increases at night so i get about 85-90% during the day and then a little above 90% or so at night.

I used to be a cable tech last century. Im not loving adding splitters to reduce signal level. Yes each 2 way you add drops you -3.5dB but you also introduce many more points of failure. More connections more cable etc. Most cable you buy at the hardware store is crap anyway if it comes with molded connectors (and incredibly expensive).

My advice pick up a handful of these and add them until you get the signal knocked down enough.

3db Coax Cable Attenuator Pad (1 Each) https://a.co/d/5l6eB32

#6

Thanks! In fact I just did that before you posted.

#7

Quite true. I have resorted to buying bulk lengths of quad-shielded coax from reliable online stores, as well as decent compression fittings. Now whenever I need a run of coax I do it myself, and create my own cables.

(When getting the cable company out to my parents' a few months ago to install new service, I already had in place the cable from pole to inside, as well as the modem ... all they had to do was couple my line to theirs at the pole, and register the MAC ... the line I ran and already had in place was superior to the crap they brought with them to use.)

#8

Curious to know if there is something that shows the signal strength in dB rather than what the HDHR show in percentages?

#9

I believe the command line tool can.

#10

Well I got the attenuators but first decided to clean up the install and had the antenna coax feed the Flex 4K directly rather than a pig tail in my patch panel. One thing at a time so I then went to check the signal first and nothing was displayed in the HDHomeRun app. I went into the flex setup screen and did another detect channels and poof NBC 11.1 in the bay area is not showing up. Only 111.1 which is the DRM ATSC3 version which I can't use. Whats up with that?

Screenshot 2024-02-27 at 12.14.24 PM
Screenshot 2024-02-27 at 12.14.24 PM1090×824 395 KB

#11

I'm having similar problems in Richmond VA. i stared with 100% signal strength. After removing all amps and splitters The HD Home Run Config (Tech) app now shows 61 - 65%. Not having as many problems now.
Screenshot 2024-02-27 at 3.40.04 PM

#12

Can you tune any of the subchannels ?

#13

Yes. I tuned and displayed the CBS channel on 5.1

#14

Are you able to elaborate? I'm not aware of any command line tool for the HDHR devices.

What is a good/acceptable dB range for single strength?

#15

On Windows, it is only shipped with the full installer/setup package. Most Linux distributions have it in their package repositories. (You can also build it from source yourself.)

https://info.hdhomerun.com/info/hdhomerun_config

1 Like
#16

I mean 11.2 11.3 etc

#17

Well 11.1 did show up this afternoon. I took out the LTE filter and it seems to be behaving better.

#18

I looked up KNTV and it appears that it is in San Jose and is RF channel 13 (210MHz High VHF). Hopefully this was just a bad LTE filter but... I had an issue where rf Channel 11 kept dropping out. I'm 7 miles from the towers and have a uhf antenna in the attic. The signal strength was about 80%. My high vhf station would just disappear sometimes. I called the station and actually told them that I thought their OTA signal was down. Yeah... The guy kind of laughed at me. He said you need to get an antenna with high-vhf capability. I argued with him and said "I can see your tower from my front door!!". He said that it didn't matter, get a new antenna with high VHF. I ordered one on amazon and that fixed my issue 100%. I had to add 12dB more attenuation to the new antenna and now that same station comes in at 97%! So if it happens again you many want to invest in an antenna with high-vhf. This is the Chinese knock off that I bought on amazon and it works great in my attic.
https://www.amazon.com/gp/product/B082DN8L6T/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

#19

Thanks I will keep it in mind if the current resolution requires more tweaking.