Rain on my OTA reception

[craigb]

I have recently dumped my satellite service, and am working on getting decent OTA reception. I live in Portland OR, zip is 97219. I currently have an EZ-HD antenna from Dennys Antennas installed on a chimney mount, about 5 feet above the peak of my composite shingle roof. It is aimed at the transmitter towers (~345 magnetic) about 5 miles away. There are some large fir trees directly between the antenna and the transmitters, about 25’ from my antenna.

During dry weather, I get signal strength readings of 50’s to 80’s for all channels (at least the ones I am interested in). However, when it rains, or shortly thereafter, signal strength on most UHF channels (2, 6, 32, 49) drops significantly – chans 6 and 32 drop below 30 and become unwatchable. Signal strength on the VHF channels (6, 8, 10) drop some to low 50s, but are still acceptable, generally.

I could possibly move the antenna to a location to the side of my driveway, where I have a mostly clear view of the transmitters – partial obstructions (trees mostly) are at least 100’ away. I could probably get it about 10’ above ground at this location. I haven’t tried this location to see how it would work. This would mean adding approx. 75’ more coax between the antenna and the receiver ( to the current approx. 35’).

I would appreciate any suggestions that would help with my reception in the rain. If I get crummy reception in the rain here, it is a big problem, cause it rains all the time!

[Electron]

The tvfool radar plot report is required.

Do as the other question askers do and Do This -> http://forum.tvfool.com/showthread.php?t=4.

Use the Exact address and make the antenna height 25.

How many Tv's are/will be connected??

[craigb]

Sorry - here is a link to the report : http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d1349a446e361c8

Currently, one TV (actually a TIVO DVR) is connected. Possibility of a second TV in the future.

[Electron]

Aim the EZ HD antenna at about 345 degree magnetic compass.

Here is how to aim antennas , http://www.kyes.com/antenna/pointing/pointing.html.

Water in the Matching transformer (balun) and coax will degrade reception.

Replace the matching transformer and the coax that connects to the matching transformer.

Look at the http://www.hollandelectronics.com , web site and find the , live rubber self fusing tape that will seal out water from the new matching transformer and coax.

To help keep water out of the matching transformer , route the coax so the coax goes up above the antenna and then loops back down to the antenna and the matching transformer then connects to the antenna.

Use a holland electronics HFS-2D splitter for 2 Tv's.

[GroundUrMast]

It sounds like you're already heading in right direction. The trees are tough stuff when right in the path of your signals. As they get wet, the attenuate and scatter the signal even more. Testing reception at the alternate site is the next logical step.

With a clear line of sight, you have plenty of signal to drive the additional 75' of coax. You certainly do not need any amplifier.

[craigb]

Thanks for the replies, Electron and GroundUrMast. I hadnt thought of the transformer, though it does have a pretty tight fitting boot on it. I will double check that and re-route the coax. Probably go up when it is dry and spray water on the transformer and see if this dupes the problem.

Assuming the transformer is not the problem, I will give the driveway location a try. The only concern I have about the driveway location is that the antenna will be perhaps 4 or 5' above the roof of my van parked next to it - the van will be positioned in the line to the transmitters. Would this likely cause a problem?

Thanks again.

[GroundUrMast]

The van is quite a reflector... Try it and see. As long as the van is not in motion, you may get lucky.

[Electron]

Here are a Truth statements.

If the matching transformer and coax has been damaged by water , putting more water on the matching transformer and coax will not prove

Just because the matching transformer and coax looks ok does NOT mean that the matching transformer and coax is ok.

A way to prove out the reception is to connect a Known to be good matching transformer and a Known to be good coax to the matching transformer and run the coax Direct to the Tv , no splitters , no amplifier , no nothing.

It is the , antenna , a Known to be good matching transformer , Known to be good coax , direct to the Tv.

And just because the tuner in the Tv is supposed to be ok does not mean that the tuner in the Tv is ok.

[signals unlimited]

It is unlikly that the transformer is the problem, but the test suggested by Electron makes sense, as it completly eliminates that possibility of transmission line problems. When soaked the trees will cause the symptoms that you are having.

As for the van, you can rule that out as a potential problem. I have a van with antenna mounted as low as 24" and 25 feet of extension. I use it daily for signal testing and have never had a near by reflection problem at any heigth. See the van on my site www.tripleplayantenna.com installation and site survey page.

[Electron]

Trees and tree leaves do a real nice job of absorbing and reflecting tv transmissions.

Wet leaves do a fantastic job of absorbing and reflecting tv transmissions.

It is best to move the antenna to a location that has less trees or no trees or other obstructions.

A larger antenna will collect more signal , you can try a Winegard HD7696P antenna.

A preamplifier Will Not help your reception situation.

Your location has plenty of signal , position a antenna to get it.

[signals unlimited]

The EZ HD is all of the antenna you will ever need for stations 4.5 miles away.

Did you try the subsitute coax/matching transformer yet? I have found some of the new matching transformers to leak badly. The worst one is the Philmore. It leaks even with the boot properly installed. Other Chinese models will too. The problem is so bad that I have been using a product called Cold Shrink to wrap all the way from the coax, over the connector and to the end of the caseing, then siliconing the input end.

[Electron]

I quote from elsewhere on this question askers post.

" It is unlikily that the transformer is the problem "

The word 'unlikily' is likely not a typo because it is followed up with ,

"but the test suggested by Electron makes sense, as it complety eliminates that possibilty of transmission line problems , "

Is it just me or is there mud stirring often going on when I print something and say something.

Like I said just because the matching transformer looks good does not mean that the transformer is good.

Self fusing rubber tape will stop water leaks. The self fusing rubber tape works so well that the only way to get it off is cut it off of what it is applied to.

Self fusing rubber tape works so well that it is often better to cut off the part that is applied to and start over with new.

Use No boot , when using self fusing tape.

And sometimes a matching transformer is bad just because it is bad manufacturing internal connections damage.

[craigb]

I did try soaking the transformer with water, and this had no effect on reception in otherwise dry conditions. Reception on all channels is good.

So I moved the antenna to the driveway location temporarily, 15' above ground, with a mostly clear view of the transmitter towers. The "signal level" readout by my receiver is higher on all channels, and yesterday I was able to check the levels during rain - they were very close to the same levels as when the weather is dry. This is with the same antenna and transformer, albeit different coax from the antenna.

So, I am going to make the driveway installation more permanent and call it good. Thanks for all of the good advice!