Setup is HD Extend with Mohu Sky antenna connected by Ethernet to Apple 2TB Time Capsule (802.11ac) wireless to Apple TV (4th gen). I get 15 channels and the set up is working very well for most channels. The two most powerful local HD stations are having “stuttering” issues with some pixelization that is annoying enough that it is difficult to watch and listen to. All other HD channels and SD channels show no issues. Any suggestions would be very welcome. I have tried all of the transcode settings and they just make the problem much worse.
Can you bypass the amplifier?
Yea try removing or unplugging the amp. Since your signal is already strong, the amp is distorting it.
I did try that and checked various channels but it had little effect. Some of the more distant channels showed some stutters and the stronger ones still had some issues. I have ordered a variable attenuator to put inline and test at various levels to see if I can find a “sweet spot”.
In order to continue troubleshooting, can you advise the symptoms I would see if the signal was too weak? I am associating the periodic, brief pixelization and audio gaps as symptoms of a signal that is too strong but I’m not sure what a weak signal would produce. I have another tv that is using the antenna signal directly and not through an Extend unit. My next step is to check its channels and see if any of these effects are present. The attenuator won’t arrive for several days but this is not an emergency. I am almost ready to “cut the cord” with cable as soon as my home phone number is ported to my Ooma hub - probably a week or two.
The symptoms are pretty similar, as the signal is distorted in both cases.
One thing that might help is looking at the web interface of the HDHR under tuner status to see what the signal strength/quality look like.
Ok. Where do I find “tuner status”? I don’t see it in the settings screen.
With amplifier in use the strength is 100%, the quality is 98%, the streaming rate is 12.697 with no transcode profile and symbol quality at 100%.
At these rates watching WBOC (CBS affiliate in Salisbury, MD) NCAA March Madness we still have 10-12 audio stutters per minute with light pixelization in the center of the picture when the stutter occurs.
I’m refreshing every five seconds and always getting 100% signal strength but getting quality readings as low as 70% when stuttering occurs.
It is the signal quality that you need to look at, not signal strength… the signal strength will always be 100% if you are using an amplifier since it just adds power to pump up the db to that level. Also, anytime symbol quality drops below 100%, this will cause some kind of degradation to the channel (ie: pixilation, stutter, audio pop, etc). You are probably getting periodic interference (or multipath reflection). It may help to further adjust your antenna.
The antenna is aimed directly at the strongest stations and is in the attic. I have a variable attenuator on order and will try adjusting the signal strength to see if I can improve the quality.
Ok, variable attenuator made no difference to results - took it out of line. Found that I had the mohu amplifier in wrong place so moved it in front of splitter. Put an FM trap in front of the amplifier to reduce impact of several local FM stations. Only local PBS station comes in with PERFECT reception on Channels.
Here are the stations I am trying to perfect:
WBOC (CBS) channel 16.1 (real 21) - 13 miles - 740 (ERP) - 340.2 degrees
FOX channel 16.2 (real 21) - 13 miles - 740 (ERP) - 340.2 degrees
WMDT (ABC) channel 47 (real 47) - 16 miles - 350 (ERP) - 322.5 degrees
WCPB (PBS) channel 28 (real 28) - 5 miles - 132 (ERP) - 338.1 degrees
Here is my setup:
Mohu Sky antenna near window in attic (20 feet above ground) aimed at 330 degrees with FM trap in line after antenna followed by Mohu line amplifier followed by 2-way splitter followed by 30 feet of premium coaxial cable to HD Homerun Extend unit on one line and 30 feet of premium coaxial cable to tv on other line.
Current results are perfect reception on PBS but choppy pixelization on other three stations- all with 100 percent signal strength but widely varying signal qualities with 98 percent at high and dips in the 50’s 60’s 70’s and 80’s with no apparent reason. Closest line of trees (50 ft oaks) are 150 - 200 yards in front of the house - no trees on the property.
Any thoughts before I raise the white flag and look for an antenna technician in the Salisbury MD area?
You could test to see what happens when you put the Mohu Sky on the outside of the window.
Thanks, I’ll try that tomorrow in the daylight. Got home this evening with no changes to the setup and for the past 15 minutes had no drop outs or pixelization. Strength has been a steady 100 percent and quality has had a baseline of 89 percent with 60 “spikes” up to 91, 93, 95 and 98 percent. The app I’m monitoring with samples every 2-3 seconds so these spikes were small and had no audio or visual evidence. Not sure why the improvement but will continue to monitor.
Your antenna is receiving electromagnetic waves. They are affected by the weather, and by the time of day. They can by ducted by the troposphere. They bounce off the ground, and buildings, and metal things like cars. Sometimes, other electronics can produce interfering signals, and they can be completely blocked by hills and trees. It definitely takes some time to set up right.
I live significantly closer to the broadcast towers and it still took me a couple months to get all of the channels perfect. One of my antennas is also a Mohu Sky. In my case, it works significantly better on the outside of the window.
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I’ll definitely try outside the window tomorrow. What other actions did you take to resolve your issues?
I am sure your environment is different, but I guess the method is the same. I spent time watching my signal levels at various times during the day and looking for antenna positions where I could prevent the signal from breaking up.
Also, signal quality is a good baseline for aiming the antenna, but if you have 98% quality with frequent drops to 60% and then back, then that is not a good place.
It is possible that a signal quality of 60% could be a perfect picture, as long as the missing bits are able to be reconstructed (100% symbol quality). But with a wildly fluctuating signal, the error correction is probably not going to work. So try to find a place where you have the best signal quality possible (shoot for 75% or higher), but without drastic drops.