OTA Interference issues / HDHomeRun support not helpful

#44

Picked up one of those grounding blocks.
Attached a 3 prong power cord to it, just the green ground wire.
Put it inline of the coax, right at the tuner, plugged the cord into my ups outlet that is grounded(tested with outlet tester) also tried direct to the wall outlet, not UPS.

Tried right at the end of the short built in cable of the on the antenna, where my coax connects to it, plugged cord into wall outlet. Even tried just a wire wrapped around the water pipe in the floorboard radiator heat to the ground block.

No change.

So....its not a grounding problem.

#45

Sounds like you did ground the coax, although hot water pipes are not a good ground.

I'm thinking since your lower frequencies like 201 MHz (VHF-Hi) are affected more, it's noise being picked up by the antenna. There's a post on the SD forum of an installer finding LED bulbs causing interference at 201 MHz even though the quad shield RG6 run is 20 feet from the bulbs https://forum.silicondust.com/forum/viewtopic.php?f=113&t=75307

You'll probably find the higher the frequency, the less interference you're getting.

#46

Well...i thought that too. but....

2.1 at 593mhz is nearly as sensitive as 11.1 at 201mhz.

Also, if anything, adding the ground adapter, made things more sensitive across the board.

I again, just tried a short coax setup. A new 12ft RG6 QS cable, and moved the HDHR to the end of that, which puts it just on the other side of the wall from the room the antenna is in, and ran a longer ethernet cable.

No change, just like before when i tried that.
So does not seem to have anything to do with cabling, length, quality, shielding, power cords, ground.
Must be the actual antenna that picks up the interference.

Once i get the new Channel Master LTE filter and high pas filter...see if that affects anything at all, that seems to be my last idea.

#47

As much as I liked the mohu and how it mounted on the wall, etc, after a few years of never having a good signal I gave up on it and finally got a cheap rca attic antenna from Walmart. Is yours mounted in the same room? Might I suggest eliminating the coax with a male to male adapter. You could also add a second antenna hooked up backwards through a splitter.

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#48

look up the ranger antenna, it has a short integrated coax cable and a female connector.

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And no, it is mounted above a window the the second bedroom, one room over from my own. (single level 3 room L shaped corner apt unit) liv/kitchen is top part of L, back bedroom, bottom part.)
And like i said, i plug in the offending electrical devices, in the back corner of the living room, farthest away possible, and 3 walls between it and antenna....still causes issues.

#49

Ok, I see. You could still try running 2 antennas though.

#50

If the issue truly is the antenna picking up things, then doubling the antennas, would double the interference i would think.

#51

Hook up a piece of coax with the copper exposed as the antenna and see if it gets any channels, just one, and test your devices. Would be like trying a different antenna. Mohu left a very bad taste in my mouth, I don't think I'll ever do that again.

#52

I have tried 2 other antennas, the original Mohu Curve i used at first for a time, but could not get some channels in well, like 11.1. And some old Radio Shack powered uhf/vhf antenna thing with a flat panel in the center and 2 extendable whips.
They all react the same in my testing.

I am done messing with this for the day, but, the bare wire things, may give that a try tomorrow. But i don't expect any different results.

If only Locast could bump up their bitrates a bit, even just 500mbps, preferable 1,000, would be just fine using that.

#53

To be clear, I’m talking about a change outside of your apartment. It’s been clear you have changed nothing, but are getting interference.

Signal strength is only part of it, in the case of interference, signal strength can be the same, but if your SNR is now worse (from something between you and the transmission locations, whether local or remote), it would cause the scenario I am describing where interfering appliances previously did not have an affect, but now they do.

Did your old photos show any difference in the SNR? I think the HDHR app has a reading for that in the tuner stats?

#54

So I noticed minor interference from the Vornado fan. I have it right next to the tv in the bedroom, one floor directly above the HDHR. A very minor blip when I turned it off. And it also reminded me that the central HVAC also creates a minor blip of interference when it turns on/off and also did this with a Hauppauge tuner before I got a HDHR.

#55

If you flip the switch back and forth continuously for about 10 seconds or so between my medium and low high for me that continuously glitches out the TV signal quite badly. I know you don't normally do that and normal everyday use of the fan but it's something I noticed.

#56

Some odd interference patterns.... makes me wonder if the ground on your house is properly connected to the ground rod. If it isn't, your supposed ground wouldn't really be a ground, but one big antenna.

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#57

Well, its a 3 story, large, 300 some unit apartment complex.
I am on 3rd floor in a corner unit.
They have been doing renovations over the last 2 years.
Replaced the flat roof last year (and all the cable tv and ethernet wires are run up there and some were damaged/cut by the roofers. but no electric cables are up there)
Replacing patio doors, refurbishing the outside stucco and trim.
Re-modeling the interior of the units, new kitchens etc.

They have not done any re-wiring or work to the electrics or in wall wiring anywhere that I know of.

It certainly is possible that something among all that re-modeling and maintenance, has changed the overall environment, or knocked loose some core electrical things or something.

But, I could never know for sure, or do anything about that.

I guess maybe, i could one of those giant battery box travel/camping battery pack, things. And run the massager based items off that...at least then, when my back or legs hurt, or other uses....it won't cause the TV to go out.

#58

So there’s potentially a massive amount of new metal all around the building that could be adding multi path distortion?

#59

New flashing on the upper roof edge, but, same thing that was there before.
And they painted the outside walls.
But that was mid last summer (2020)...so, if that was the cause, I would have noticed something back then probably.

#60

300 unit apartment....you have a constantly changing environment. Maybe a new neighbor put up a giant mirror or other metallic item nearby. Who knows what comes and goes in your nearby environment. You probably have someone moving in and out all the time.

I thought you said that you isolated the stuff using off-line UPS's. That would eliminate any powerline related path.

I think the others were likely on track...the fans/switches are emitting RF interference and that is getting picked up by your antenna. It could be that they've degraded somewhat and are emitting more now than they did a year ago. You could try moving the antenna outside (long coax) to isolate it from your gear and see if that helps.

#61

I see you noticed the Avant X. I seem to be having a somewhat similar issue (maybe). There's a powerful UHF channel just 3 miles from me. It randomly spazzes out, making the TV picture very difficult to watch. SiliconDust looked at the diagnostics and said I had an overloaded signal.

First step: remove pre-amp. Second step: add a splitter to reduce signal. Third step: add ANOTHER splitter to reduce signal even more. The strength of this channel is still pegged at 100%. During testing today I had the same problem. After a certain period of time one of the tuners sometimes starts to go haywire. Not always the same tuner if I recall correctly. One way to monitor this is by using TSReaderLite and letting it run for a couple of hours. Instead of sitting and staring at the screen in real time, you can see how many errors have racked up during the testing time. I've only found a couple of cases of household motors that cause momentary blips in the signal - one being my dishwasher.

My next step is to try the Avant X which can SOMETIMES reduce the power level using its automatic gain control. What can I say? I like playing with crazy gadgets. I'll try to come back here to see if it helps.

#62

Instead of adding splitter after splitter (since each 2 way splitter only attenuates the signal 3.5db) just pick ip some inline attenuators. You can get them in any value that you need. I have the same issue. I attenuated the signal 12db and I'm still at 100% on most channels. If I drop it - 15db then I go below 100% so 12 is my sweet spot.

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#63

It’s funny hearing about issues with being too close to the transmission source, but I do remember reading about problems with that when studying for my technicians license.

On the other hand I had to put my server at a family member’s house to get within 40 miles of the transmission source (metropolitan area) and on the other side of the mountain between there and here.