Dropping TV channels

one tv has a stronger programmer and robs the sigal from the weaker one

newman fulltimer wrote:
one tv has a stronger programmer and robs the sigal from the weaker one

X2
Unless the TVs are identical models and the same age, it is likely one has a more powerful (or sensitive) detector. Hence, one will get more channels than the other. The weaker the signal (i.e., downstream from the splitter) the fewer channels will be picked up.

I've heard of a few with similar problems that changed out the cheap splitters with some of better quality and found it resolved issues with over the air and cable signals. In some cases the connectors were loose at the splitters causing problems.

Ok similar issue on a 2017, both TV's same brand different sizes, do the scan on both, one at a time, farthest gets less channels than the one at the antenna booster. I read the post on the splitter and will buy some new to replace the factory's.

punomatic wrote:

newman fulltimer wrote:
one tv has a stronger programmer and robs the sigal from the weaker one

X2
Unless the TVs are identical models and the same age, it is likely one has a more powerful (or sensitive) detector. Hence, one will get more channels than the other. The weaker the signal (i.e., downstream from the splitter) the fewer channels will be picked up.

Nice guess but not true.

What really is happening is NOISE.

EVERY electronic item emits RF noise (AKA RFI) which INTERFERES with other electrical items.

The digital broadcasts called ATSC is extremely sensitive to interference.

Turning one TV on is creating interference which is affecting the OTHER TV and vice versa. TVs are chock full of devices which create RFI, switching power supplies if cheaply made can leak large amounts of RFI. If TVs are older LCD with fluorescent backlights the inverter for the backlight can generate large amounts of RFI.

The only thing that can be done is to find away to overcome the noise, that means improve the antenna, feedline and such.

Typically most RVs use passive RF splitters which rob you of signal..

A two way splitter is a 3.5 DB loss which is slightly more than cutting the signal in half..

Replacing the passive splitter with a amplified coupler can often overcome local RFI in some cases.

Your antenna may not be an amplified model, on with a preamp at the antenna helps to overcome the small low gain antennas used on RVs..

Feed line, make sure it is RG6, many manufacturers take a shortcut on this and use RG59 which has a much higher signal loss.. RG6 is larger in diameter than RG59.

Make sure no other electronic devices are causing interference, many LED lights have cheap power supplies that cause interference, your multistage converter which is a switching power supply is another source..

Turn all other items off to check to see if they are causing problems..

If all that above fails you might need to simply replace one or both TVs with better TVs, especially if these are OEM factory RV installed TVs which generally are not of much quality to start with..

Veebyes wrote:
Here is a frustrating one. Have 2 TVs. Over the air only. No satellite. Yes set for over the air at the ant/cable button. We have a Jack ant.

Upon arriving in a new area each TV, 2 of them, is scanned for available channels. The crazy thing is that one TV will drop channels when the other is turned on. The one losing the channels is the one furthest from the antenna after the splitter to feed each one.

It is almost like a water pressure system where the water will go to the closest tap from the supply the easiest if both are on.

Any techie with an idea?

I found out that all TV's are "NOT" created equal. Some have a better antenna reception circuit board. I have one TV that will pull 10 channels and when I put a different TV plugged into the same outlet and parked in the same spot can barely pull in 6 and usually drops 2 of them.

So many think it's the RV antenna when actually its the TV. I took that one TV into a TV Repair shop (yes they do still exist) and I had them replace the antenna connection circuit board. Now that TV pulls in over 18 channels off the batwing.

newman fulltimer wrote:
one tv has a stronger programmer and robs the sigal from the weaker one

BULL, that can not happen. Impossible.

But what CAN happen is RF-Interference, The TV signal is "On the edge"

(With the old analog TV as signals got weaker the picture got progressively worse, but with Digital it's GOOD GOOD GOOD GOOD GONE as the signal gets weaker or rather the signal to noise ratio gets worse)

The one set is generating noise.. OR. one very slight posibility, Very slight indeed. THe RV is wired wrong.

Back in the old days of Flat TV antenna wire. This was fairly common but with Coax I've not heard of it.

It may also be you have a bad Splitter.. Some of them are better than others.. But if the only splitter is the Winegard wall plate or Matrix Switch (box of many buttons) Those are GOOD splitters. well designed. I"ve had some el=cheapos however that were not so good.

Both TVs are Samsungs. Both were bought together so same age, different sizes. The ant is a newish Jack that has a little light on it, assume indicating an amp of some sort. No LEDs in the trailer.

That leaves me with the splitter which came with the trailer. Will check connections when next on trailer, next April, & maybe find a better splitter.

While I think the RF interference is likely, another possible explanation is a changing VSWR. The impedance if the TV antenna is likely 75 or 300 ohms. The cable maybe 60 ohms or 50 ohms or 300 ohms if it's a flat cable. The splitter if used is unknown and then there is the input impedance or termination impedance. Unless all these impedances are equal you get interactions from a voltage standing wave ratio reflected back towards the source and then to a downstream device.

Edd505 wrote:
Ok similar issue on a 2017, both TV's same brand different sizes, do the scan on both, one at a time, farthest gets less channels than the one at the antenna booster. I read the post on the splitter and will buy some new to replace the factory's.

Not all splitters are created equal. When we dropped DirectTV and DishTV from the house and went back to over-the-air, I installed an antenna on the roof of the house using the existing wiring and splitters that both satellite systems left in place. Neither the DirectTV splitter or the DishTV splitter worked. I have about 500 feet of coax in the house, split to 7 rooms. They all join at one splitter.

I'd get a good signal in one room, and nothing in another. Moving televisions around, the signal seemed to follow the television. I had some old splitters from old remodel projects that didn't work either. I tossed all of these away.

I finally went to Radio Shack and got a brand new one. It had like 12 splitters on it. Well, it wouldn't work on anything in the house. I had better success with some of my older ones.

I finally went to Lowes Home Improvement and out of desperation got a different (10 way) splitter. And it worked! Every room in the house had the signal.

Mind you, in the house, I have no booster, and every television gets about 60 channels ... over the air.

The trailer, with the booster on, get's one more set of channels... 30.1, 30.2, 30.3 (Decades). We don't get that in the house.

So, splitters do make a big difference. I advise, just go straight to Lowe's and get one of theirs.