# Antenna Amplfyer Loss Of Gain



## Ghostmaker (Mar 2, 2013)

What are you using for an interior antenna?


----------



## rjordan393 (Sep 15, 2010)

I am using a Mohu indoor type because I live in an apartment. It is attached to a window.
UPDATE:
I believe the model is mohu 30. I should have saved the installation instructions. It must have been a year ago that I added a amplifier and do not recall what the results were. So now it has been removed and I still get some interference and a little less then when the amplifier was installed. I decided to try another product called "Clearstream Flex Amplified UHF/VHF Indoor HDTV Antenna that comes with an external 20 gain amplifier and am awaiting delivery. If that does not work, then I'll have to call in a service technician.
When I first noticed the interference a year ago, I then subscribed to a streaming service that gave me all the local channels and more. But the company had to stop operations recently. So all I had left was my roku. I been getting my news and movies since then but no local channels.


----------



## supers05 (May 23, 2015)

You have to know where the local channels are broadcast from. Look it up online. There will likely be more than one. Point the receiving side towards the transmitter. (broadcasting tower) If that is on the other side of the building, you're a bit out of luck and will need a very decent antenna to pick up the signal through the building.

PS. That antenna looks very small. It's gain is probably quite low. It makes sense for an apartment in the same city as the transmitter, but I wouldn't expect a great range from it, regardless of its claims.


----------



## rjordan393 (Sep 15, 2010)

My antenna measures 9 " X 11.5 ". So it is a smaller then the one I got on order which is 12" X 16". I checked out the specs on the Mohu 30 and could not find online any mention of what the gain is or if it is a non amplification type.
I have two amplifiers. One is a Winegard and no mention of its gain and a Antennas Direct which has a 20 db gain. Neither were satisfactory.


----------



## ktkelly (Apr 7, 2007)

Where is the amplifier in relation to the antenna (at TV or at antenna)?

How long is the coax run?

Is there no signal strength indicator on the TV (typically in settings)?

Can the antenna be placed on a balcony instead of inside?


----------



## supers05 (May 23, 2015)

rjordan393 said:


> My antenna measures 9 " X 11.5 ". So it is a smaller then the one I got on order which is 12" X 16". I checked out the specs on the Mohu 30 and could not find online any mention of what the gain is or if it is a non amplification type.
> I have two amplifiers. One is a Winegard and no mention of its gain and a Antennas Direct which has a 20 db gain. Neither were satisfactory.


Every antenna will have a gain. That is their very point. Some designs are more directional than other designs. The panel type is relatively directional. The pictures I could see of the muho show that it's missing the forward crosses that make that design decent. That means that it's gain. Is likely very low. I wouldn't expect it to pick up much unless you're line of sight within maybe 50 miles of a decently powerful transmitter. (there's a maximum power level, but no minimum. Stations can choose to save power if they are low budget. That means to you that some stations will come in clear and some you'll have trouble getting even if they are side by side.)

Active amplifiers are ones that require power. With those, garbage in equals garbage out. They are best connected with the shortest cable possible to the antenna. The cable to the TV can be much longer. That's why some antennas have them built in. Quality also plays a huge role, but even a cheap amplifier should help you a bit, as long as you're getting any signal. 

Unfortunately with digital signals, it's mostly an all or nothing game. Either you get great picture or no picture, depending on the signal strength. With analog it would be more of a gradient as you lost signal making it easier to align things. Again, you'll have to figure out which stations you want and in which direction they are located. After aligning, try it without the amplifier first. You may have to use multiple antennas if they are 90° apart. You can use a basic, passive splitter /joiner so that you don't need to switch cables. 

In apartments, I typically put the antennas in closets or other storage rooms, up against the wall. It keeps them out of sight, but then you can use larger antennas. Ugly antennas in windows or on balconies is first thing everyone complains about. The balcony is the ideal place though. Some apartments have good antennas on the roof and distribute it throughout the building.


----------



## SW Dweller (Jan 6, 2021)

I have become pretty good at my OTA equipment. My neighbor works for a TV station and I asked him about a signal meter. He responded save your time and money. Move the antenna around until you find where it works best. He stated with no doubt in my mind not to deal with an amplifier, they amplify the noise as well. Signal problems? get a bigger antenna. Not one with more gain, physically larger. I did and found the right place for my antenna on the roof. It was not on my chimmeny like I had been trying.

OTA is location, location, location. TVFool will help a lot. It will also tell you how to aim the antenna you have and what to expect from it. Antennas do not see over the horizon nor around buildings and trees. 
Next comes splices or connections in the cable from the antenna to the set. Each connection I remember looses ~5db. 
Are you using the proper cable? There is more than one type and they are not equal.


----------



## Dave Sal (Dec 20, 2012)

Check out this video from Antenna Man. Go to the 5 minute mark or so as he talks about a similar flat antenna as yours.


----------



## rjordan393 (Sep 15, 2010)

Thanks all for all replies. But I got it partly fixed I think. While studying the problem, I remember seeing some advice on the net about not placing the antenna near steel. I knew my sliding door is all aluminum so I thought. So I go get a magnet and checked the frame and found that there's a steel channel sandwiched between the two panes of glass. The left side of the antenna was just 4 inches away from it. So I moved the antenna 6 inches to the right. I immediantly saw a big improvement in reception. This improvement diminished a little bit after 2 hours of broadcast. So something else is at play here. It may be not enough gain because the skies became overcasted or length of the cable is too long ( 38 feet).
I had to use two lengths of cable. one lenghth is 28 feet and the other is 10 feet. But there's one thing I overlooked. I checked both cables to see if they are both rg6 and the 10 foot length is rg6u. I never heard of it before and will change it soon. I had to use a magnifying glass to attempt to read it because it indented on the cable and white on white. But its either a letter u or a number. It is hard to make out. I have not tried re-installing a amplifier back on yet and will do so after the football games are over.


----------



## Dave Sal (Dec 20, 2012)

I had to trouble shoot a rooftop antenna problem last year for my parents. Turned out it was a bad cable. You'd be better off with a high quality, single run of RG6 cable as any coupler between two shorter lengths will probably add noise or cause a loss of signal.


----------



## ktkelly (Apr 7, 2007)

SW Dweller said:


> He stated with no doubt in my mind not to deal with an amplifier, they amplify the noise as well.


Both right and wrong.....

The use of an amplifier is a good idea. The reason for an amplifier is to overcome the signal loss in coax runs. Mind you, 30' of coax will have a pretty low amount of loss. Most likely down around 2db to 3db.

Incorrect use of an amplifier WILL be a problem. Most install the amp close to the TV where it will do nothing good, and will do everything bad.

For the OP. The RG6U will not be the problem. As long as the connectors are clean (no corrosion) any RG6 is fine.

If you have the space, get a Channel Master Omni+50. If that won't work, not much chance any antenna will, other than mabye the Channel Master Extremetenna 80.

For an indoor I've used the FLATenna+, but I suspect it might not give you what you want.

Honestly, most antenna manufacturers tend to overstate the range for their products. I've found that Channel Master tends to be more honest with the specs. Remember, they have been in the antenna biz, longer that anyone else.

You see those Ebay claims of 200 to 900 mile range specs? That's impossible.....


----------



## diyorpay (Sep 21, 2010)

I believe Mohu type antenna are great or less great, depending on the weather conditions and the precise receipt of signal. And, the broadcast stations may not be keeping output levels consistent. Lots of varying factors.

I have found that, after velcroing panel to window, certain adjustments may be necessary on any given day to get certain channels. Some important stuff to experiment with included wood shaped like a drumstick (to vary depth away from glass on one side only), aluminum foil, an old broken tv antenna extendable ears, stuck behind but sticking out, at different extended lengths. 

"Set it and forget it" is not likely possible. "I know you're out there somewhere" is more likely.


----------



## rjordan393 (Sep 15, 2010)

Right now I am awaiting a reply from the "Äntenna Man" as to what type of antenna will serve me best. All I want are the local stations from Philadelphia, Pa. I live 21 miles north of their transmitting towers. The one thing I do not understand is I cannot receive vhf channels. I might even go back to Rabbit Ears if that is what it takes.


----------



## diyorpay (Sep 21, 2010)

The FCC allowed original vhf stations to stay at a vhf frequency or move to a uhf frequency.
See pic attached. In NYC channel 7, ABC stayed at original vhf frequency but channel 2, CBS moved to uhf channel 36.
Check out Philly:








DTV Reception Maps







www.fcc.gov


----------



## snic (Sep 16, 2018)

I suspect that your problem is NOT the amplifier. I installed this antenna in the attic in two different houses. It comes with a cheap, low-power amplifier that is essential for it to work. In both houses, it picked up nearby stations fine, but distant ones were very hit or miss (mostly miss). Then I moved the antenna to the roof, mounted to the gable so the body of the antenna is above the ridge. The difference is like night and day. We get dozens of channels from far away crystal clear. And I'm using the exact same el-cheapo amplifier, with cable that is twice as long as what I used in either house, going through several coax-coax connections.

This has made me a believer that the factor that makes the biggest difference in getting an OTA antenna to work is outdoor vs indoor. Of course poor/nonexistent amplification, bad connections, or giant obstacles between the station and your antenna will always cause problems. But this is for certain: if your antenna is inside, the radio signal power is reduced by your walls by a LOT. Getting a bigger/more expensive antenna and changing your amplification are unlikely to help unless they are malfunctioning. Put your antenna outside.


----------



## supers05 (May 23, 2015)

snic said:


> ... I installed this antenna in the attic in two different houses. It comes with a cheap, low-power amplifier that is essential for it to work.


That isn't an amplifier. The adapter is a DC injector. The amplifier is built into the panel.

Walls, buildings, trees, hills all degrade the signal. Digital signals are mostly all or nothing. Either you get a great single or you get nothing. Where analog you see the degradation long before the digital cuts out, but you don't lose analog completely, and can still make out the image from the static. It's one of the biggest reasons people have trouble getting digital OTA to work. You have nothing until you suddenly have great picture.


----------



## rjordan393 (Sep 15, 2010)

Ok. It took a while reading some of the "How to's" and other advice which gave me a clue. It was about 6 years ago when I sold my residence and moved into an apartment. After settling in, I called Comcast for service. the technician installed a digital to analog converter box. Being as I am not a tv geek, I did not question it. All the local stations then were received. I think philadelphia stations WPVI and WHYY which are vhf were also received. Now some may wonder why I needed a converter. Apparently my tv has a analog tuner because it was manufactured in 2006. About this same time most or all tv stations switched their signals from analog to digital. Now I do not recall why I disconnected the converter. So after I read the how to's and advice, I decided to re-install the converter. Now I get 36 channels, most of which I will not watch. However I still do not get WPVI Channel 6 and WHYY channel 12. But the Antenna Man got back to me today and has a fix to be able to get WPVI and WHYY. I am looking into this further as I expect a new antenna to arrive on thursday and I will check to see if will receive VHF signals. If not, then I'll just send it back. The Antenna Man said my Mohu cannot receive vhf.
So I am pleased with the results I got with the converter box.


----------



## Steve2444 (Sep 28, 2020)

OLD Cb'er here ...

A larger antenna is "always" better than using an amp, even with a larger antenna sometimes an amp is an added benefit as well. But a higher "gain" antenna is what you start with. Omni or Directional. Depending on the need.

Old antennas I have had, Moonraker, stacked v-quads, antron 99. mobile, 9ft francis whip

CB or TV antenna's work the same sort of.

breaker breaker 19 hic
Ah the good old days, 

Can't tell you how many garage doors I have opened from the street, when I keyed up, with my mule on


----------



## supers05 (May 23, 2015)

rjordan393 said:


> ... I expect a new antenna to arrive on thursday and I will check to see if will receive VHF signals. If not, then I'll just send it back. The Antenna Man said my Mohu cannot receive vhf.
> So I am pleased with the results I got with the converter box.


Basically anything that fits inside your apartment is not likely to be able to receive VHF, short of rabbit ears that is.


----------

