Antenna advice needed in Portland, OR

[dovienya]

Hello!

Sorry for my first post to the forum being a request for help, although I also expect that that is somewhat common here.

I am currently trying to "cut the cord", but am not particularly willing to do so if I cannot at least maintain a DVR with the basic broadcast channels. I purchased a Tivo Roamio OTA and have been experimenting with antennas, but have not had much luck yet.

Here is a link to my report: http://www.tvfool.com/?option=com_wr...f1f058105d6659

I live in a three story townhome/rowhouse. It is a rental, so roof installations are not particularly viable, nor is there any attic space. There are bay windows on the 3rd floor, which face north, but also give me a nice view of the west hills. Unfortunately, despite how close I am to the towers, I am on the downhill slope AWAY from them, and I think that is where my problem is.

I have tried the following two antennas so far with poor results:

http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

This one could get a couple of channels to be semi-viewable, with quite a few pauses and breakups. That is with the amp. If I removed the amp, pretty much nothing.

http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

This one gave me better results when pointed towards the right spot up the hill. A few channels came in pretty well, again with the amp hooked up, but still only were around 60 on the Tivo's power meter. Other channels such as Fox were still completely absent.

I have another week that I could return the Tivo if I need to. I also don't actually want to do this. I am thinking of stopping at Best Buy this weekend and picking up a clearstream 2 to see if that gets me anywhere.

I have a balcony on the 2nd floor that may give me some mounting options for an outdoor antenna. I would lose some height though, and gain a tree in the way, so I am not certain if that would actually be a benefit.

Any and all advice is greatly appreciated! My apologies for the long post!

Thank you.

[rabbit73]

Hi dovienya

Make it a C2V, because you have some VHF channels.

You should get down to Fox and maybe even down to KPDX real channel 30 if you are lucky and if the C2V has a clear shot to 277° magnetic.

If the bay windows have lowE glass, that can block signals.

Trees really mess with UHF (real channels 14-51) signals. See attachment 2

Unfortunately, despite how close I am to the towers, I am on the downhill slope AWAY from them, and I think that is where my problem is.

Oh, yes. I see that.

[dovienya]

Rabbit,

Whoops! Yes, the 2v is actually the one I had been looking at. They have it at Best Buy, and I actually got impatient and decided to run buy one during my lunch break. It's a three day weekend coming up, so I'll have some time to spend screwing around with an antenna. Unless I luck out with it inside, I have I suspicion I will be clamping it to a broom handle and waving it around like an idiot from the 2nd floor balcony for part of the weekend.

Ultimately, I want/need to get the "usual" channels to get this far enough along to justify cutting cable TV. I am very much hoping to be able to get ABC, CBS, NBC, OPB, KPTV, Fox, and CW or WB or whatever they call it these days.

I had not even known to check for the low-e glass! Thank you for the heads up on this. I know the glass in the bay windows looks like it is "nice", so I will look for any type of indicators when I am home later today. Despite the windows having a view up the west hills, maybe that has actually been a bad place to be testing things out.

Here's hoping for good results with the clearstream! If this doesn't turn out to do the trick, I may be running out of reasonable options. I'll follow up over the weekend after I have had a chance to test things out.

[ADTech]

Low-E glass usually has a greenish or bronze-ish tinge to it when you look at it a the right angle from outside. Also, look out for aluminum window screens.

[dovienya]

Well darn, this has not been going nearly as well as I had hoped.

Sadly, the windows did not turn out to be low-e. I had hoped that that would turn out to be the case, and I had just been doing a very poor job placing the antenna in the bay windows. But no, the bay windows do seem to have the best reception indoors.

I picked up the 2v on Friday, and have spent a little bit of time with it strapped to a broom handle, going around upstairs as well as hanging out of the 3rd floor window with the antenna up closer to roof level.

The c2v is definitely an improvement over what I had been doing, but I'm still not "there". With this antenna, I can get 8 and 10 up into the 70's. I can even see that a channel exists on both 12 and 49, and if I fiddle around with antenna placement enough, I can even get them to be somewhat viewable! Of course, in doing so, I end up losing at least one other channel, most often channel 2, which I don't entirely even think makes sense if I'm understanding which frequencies are closer to each other.

I'm not entirely opposed to talking with the landlord about paying to put up an outdoor antenna on the roof. I'm about to sign a fresh two year lease, so at least I would get some return on the investment, regardless. But with the results I am currently getting I am unsure if its worth going down that road. I have spent a while looking at rooftops in the neighborhood, and don't see any antennas, just a lot of dishes hanging off the south sides of houses.

Does anyone have any further suggestions? It looks like 12 and 49 are the biggest problems for me. Getting them to even be sort of watchable seems to result in hurting the reception on other channels. Is the C2V not the optimal choice?

Also: To any Portland installers that may be reading this, if something turns out to be a winning combination, I may end up wanting to hire someone for an install!

[rabbit73]

Well darn, this has not been going nearly as well as I had hoped.

Sorry to hear that you are having problems. You have done a good job of trying different spots for your C2V.

I have a balcony on the 2nd floor that may give me some mounting options for an outdoor antenna. I would lose some height though, and gain a tree in the way, so I am not certain if that would actually be a benefit.

I think the trees are messing with your signals, sort of like looking through lace or gauze.
http://www.avsforum.com/forum/25-hdt...-part-1-a.html
His trees in attachment 2

I'm having difficulty following your description of channels received, because they are listed in different ways on your tvfool report: by call sign, by real channel number, and by virtual channel number.

most often channel 2, which I don't entirely even think makes sense if I'm understanding which frequencies are closer to each other.

The real channel number is what the transmitter uses, and determines the antenna needed. The virtual channel number is a holdover from the analog TV days, and the stations wanted to continue to use it for viewer identification. Sometimes they are the same, sometimes not.

VHF-Low, real channels 2-6 (not used much anymore)
VHF-High, real channels 7-13 (the "V" dipole attachment of the C2V)
UHF, real channels 14-51 (the double loops of the C2)

To avoid confusion just use the number for the real channel number, but add the decimal point or a dash for the virtual number. Some examples:
KGW NBC, real channel 8, virtual channel number 8.1 or 8-1

When you say 49 do you mean KWVT real channel 49, virtual channel 17.1, or do you mean KPDX real channel 30, virtual channel 49.1? My guess is you mean KPDX.

When you say channel 2, I don't see it listed on your report. Do you mean KATU ABC real channel 43, virtual channel 2.1?

In order to sort your channels out, I used this listing for your zip at rabbitears.info:
http://www.rabbitears.info/search.ph...pe=dBm&height=

Since you are having some trouble, I decided to dig a little deeper. When you were testing your first two antennas, you said a preamp helped. I wondered if you could use a preamp with the C2V, but according to the tvfool report your signals are already strong. The Noise Margin for KGW is +54.6 dB.



I then wondered about strong local FM signals that might cause interference to your TV reception, especially real channels 8, 10, and 12. I did an FM FOOL report using your zip code, and the strongest FM signal was +7.7 dBm, at 0.4 mi away!

I then did an FM FOOL report based on your estimated location derived from your tvfool report which gave -4.3 dBm at 1.1 mi; still extremely strong. I think an FM trap/filter, or 2 in series, between the antenna and the tuner would help, and they are not very expensive.
http://www.mcmelectronics.com/produc...-FM-88-/33-341

https://www.antennasdirect.com/store...on_filter.html

It seemed to help another Tivo user:
http://archive2.tivocommunity.com/ti...d.php?t=270549

[dovienya]

Rabbit:

Thank you for the thorough response!

You may well be right about trees. There are trees along the front of the house, and all my fiddling with the antenna on a broom out the window couldn't quite get above the tops of them. They're pretty much the same height as the house, although the tops of them are not very full.

I apologize for the channel number identification. I'm a bit thrown by the whole thing, myself. I'd always been used to whatever "number" you turn the TV to being the channel, so I'm still trying to get used to the current terminology. I'll list the real channels below, simply in the order that I am used to, with a few notes on their reception for me.

43 .1 .2 and .3 - KATU: I am able to get this channel fairly strongly (around 60), but invariably once I have gotten some of my "problem" channels to come in, this one disappears
40 .1 - KOIN: This one also comes in pretty well without a lot of effort. I get around 60 strength here as well, but that goes down a bit when trying to get the problem channels to come in. While I find a .2 and .3 variant with the same signal levels, there do not appear to be broadcasts on these channels
8 .1 .2 and .3 - KGW: These usually come in well whether or not I am working on the problem channels. Around 70 strength.
10 .1 .2 and .3 - KOPB: Also usually come in well, 65 to 75 strength.
12 .1 - KPTV: Seriously difficult time getting this one to come in reliably. This channel is a "problem" channel. My best results so far still only get it to around 55 strength, usually at the cost of channels 43 and/or 40.
33 - KRCW: Iffy all around. Similar results to channel 12.
30 - KPDX: Iffy all around, potentially the most problematic of them all.

I did try a pre-amp with the Cv2, but I don't feel like it is making much of a difference with this antenna. It did make a minor difference only when I was really going far afield with the broom handle experiment, using a 100' coax cable.

I went to the local hardware store today after seeing your response. Sadly, no FM trap, despite them having had about 30 different coax ends for self-install cabling, and quite a few splitters. If I don't find one local in the next day or so, I'll be ordering online. Fingers crossed that that may help out, and I thank you for the suggestion!

[rabbit73]

I apologize for the channel number identification.

An apology isn't necessary; I'm still learning too.

Thank you for the channel reports.

It did make a minor difference only when I was really going far afield with the broom handle experiment, using a 100' coax cable.

That makes sense; the cable loss is about 6 dB for 100 ft for UHF.

If I don't find one local in the next day or so, I'll be ordering online. Fingers crossed that that may help out, and I thank you for the suggestion!

Good luck, dovienya.

[dovienya]

Well, an FM trap does appear to have helped a little, in that I am able to get a few more channels to a viewable state in a single position of the antenna. A second FM trap in line seems to only reduce the signal strength a little across the board, with no other noticeable effects.

Last night's tests, with the FM trap installed and the C2V back in the bay window on the 3rd floor which seems to be the most universally usable space I have found so far yielded these results. I am only listing the channels I care about, and only bothering with the .1 variant of each for the time being.

KATU real channel 43 strength 40
KOIN real channel 40 strength 47
KGW real channel 8 strength 62
KOPB real channel 10 strength 72
KPTV real channel 12 strength 41
KRCW real channel 5 strength 32
KRCW real channel 33 strength 32
KPDX real channel 30 strength 32

It looks like strength 40 is pretty much the bottom cutoff for the channel to be viewable. Low 40s have stuttering and pixilation. Below 40 has 'digital signal found' but no picture. Interestingly, a reasonable few channels seem to like to hang out right at a power level of 32. While disconnecting and reconnecting cables, I found that KPDX for example shows 0 signal strength with nothing attached to the tuner, 32 and steady with the antenna attached, and it bounces between 32 and 0 with the coax connected to the tuner, but not to the antenna. KRCW is listed twice only because I want to receive one of those channels, although I do not really care which.

It seems weird to me that since these are all on the same couple of towers in the same direction that I am having the varying results that I am. For example, I would expect real channel 12 to have similar signal strength to 8 and 10, since they are all VHF.

Any further thoughts from anyone? I'm open to ideas!

[rabbit73]

Hi, Dovienya,

Thanks for the encouraging report about the FM filter helping. What brand did you buy? Their performance varies from brand to brand.

The signals do look better but could be stronger. How much more time and money are you willing to spend on further experiments?

[dovienya]

Originally Posted by rabbit73

Hi, Dovienya,

Thanks for the encouraging report about the FM filter helping. What brand did you buy? Their performance varies from brand to brand.

The signals do look better but could be stronger. How much more time and money are you willing to spend on further experiments?

Radio Shack brand. Turns out I have a local radio shack that is still around!

Time: A bit. I think I've decided that regardless of nearly being at the end of my window to simply return the Tivo OTA, I am not going to. I got in on the $299 deal with Lifetime service, and it looks like I can pretty easily sell it for right around that if I decide it's just not going to work out.

Money... It depends! I don't like "wasting" money, so spending on stuff that may yield no results and cannot be returned is not particularly appealing. That said, I've tried a $30, a $50, and now a $100 antenna. I'm willing to go higher if it would yield the right results, although again roof access is a problem for me.

I spent a little longer looking around my neighborhood for TV antennas. I've seen enough while shopping that I very well might have recognized one had I seen ANY house that had one up. Unfortunately, I did not see a single house with an antenna on the roof. I did however see a LOT of dishes pointing south....

[rabbit73]

What happens if you connect the antenna directly to the TV? If you said, I forgot. I'll go through the thread again.

In the attachment you can see the difference between the Antennas Direct and the older Radio Shack FM filter. The AD filter attenuates the FM signals at the low end near 88 MHz and TV CH 6, but doesn't remove all the FM signals at the high end near 108 MHz. The RS filter protects CH 6 for people that need to receive it, and does a better job of removing the FM signals at the high end of the FM band near 108 MHz.

[dovienya]

Originally Posted by rabbit73

What happens if you connect the antenna directly to the TV? If you said, I forgot. I'll go through the thread again.

I'm not certain that I had said much about that, and to be honest, it has been a while since I tried it.

I'm not entirely certain that I have tried that with the C2V in the equation. I know that I had tried it with at least one, if not both of the prior antennas. To the best of my recollection, the results were somewhat similar to the Tivo, with slightly higher strengths across the board. I think that makes good sense to me, since the Tivo has 4 tuners to worry about, while the TV only has one.

I should probably give the TV tuner another try with the C2V in it's current position, just to see if it provides any helpful information. The TV does it's channel scan fairly quickly, which makes it even less of a bother. Unlike the Tivo, which takes a minimum of 15 minutes to do a scan. I'll try to get to this tonight! (although I have been spending so much time fiddling with the TV that I haven't gotten around to springtime pressure washing yet. For the sake of domestic bliss, I may need to give the pressure washing priority tonight)

[rabbit73]

Any metal screens in the bay window, or did you avoid them in your tests?

[dovienya]

Originally Posted by rabbit73

Any metal screens in the bay window, or did you avoid them in your tests?

There are not. The "front" one of the windows did have one, although the antenna has been in the side one, which is the one facing the correct direction. Regardless, I removed the one from the front window as well, just to rule out any issues with it being nearby.

[dovienya]

I tested via the TV's own tuner last night, which I had not yet done with the C2V.

I also was reminded that the signal strength meter on my Vizio is worthless, and only either shows a strength of "0" and a status of Locked: No, or a strength of 100 and a status of Locked.

That said, all the same channels came in via the TV's tuner as via the Tivo. The channels that the Tivo cant get a picture on show up as unlocked with zero strength on the TV tuner.

It appears to me that I can get the High VHF quite well. There is a low VHF (real channel 5) option for CW, but I do not see that at all. I also get the upper end of UHF (the channels in the 40s) pretty well, but the channels in the 20s and 30s are particularly problematic.

Is the C2V the wrong antenna for me? It seems silly to me that I could potentially need something even bigger, potentially the 4V, considering I am less than 4 miles from the towers...

[rabbit73]

Is the C2V the wrong antenna for me? It seems silly to me that I could potentially need something even bigger, potentially the 4V, considering I am less than 4 miles from the towers...

Based on your tvfool report, the C2V is the right antenna for you. Keep in mind that the report is only a computer simulation that doesn't take into account trees or buildings in the signal path.

A bigger antenna, like the Winegard HD7694P would give you more VHF gain (which you don't seem to need as badly as UHF) and about the same UHF gain, but would be a lot bigger. The VHF signals can refract over the rough terrain better than UHF.

Now that you have the FM signals tamed, I put more stock in your test results and the Tivo Roamio signal strength readings that remind me of when ADTech and I helped mulliganman:
question regarding overamplification
http://forum.tvfool.com/showthread.php?t=15025

The readings that he got on his Roamio compared to your readings make me think your readings should be higher for satisfactory reception. At first, I didn't think you should use a preamp, but maybe you should consider trying one to see if it will help. You might be losing a lot of signal strength because of trees, buildings, and terrain.

If no preamp isn't quite enough gain, and a preamp is a little too much gain, you can insert an attenuator between the antenna and the preamp input to optimize the gain for your situation.

The preamps you might consider are the Antennas Direct Juice, Channel Master 7778, RCA TVPRMP1, and the Channel Master 3410. The Juice and the 3410 don't have internal FM filters; the other two do, but I would put external FM filters before all of them because of your strong FM signals. The first two are more expensive; second two less.
The Juice is highly resistant to overload.
The 3410 is a distribution amp for indoor use.
The quality control of the RCA isn't quite as good as the other three.

Update 5/29/15: Delete 3410 from the preamp list on the advice of ADTech; see later post 20.

A HLSJ also makes a good FM filter because it attenuates everything below CH 7 including the FM band. Use the common and high ports.
http://www.hollandelectronics.com/ca...-Diplexers.pdf
http://www.solidsignal.com/pview.asp?p=zhlsj
http://www.atvresearch.com/hlsjvhfba...-combiner.aspx
http://www.sterenshopusa.com/catalog/prod.asp?p=2227

[dovienya]

That thread is quite a read! I still haven't read all of it, but I have already learned of a useful new tool. By going into the device diagnostics screen of the Tivo, I can see more detailed information on the signal strength. Also, this screen updates WAY more quickly. At the normal tuning test screens, I will move the antenna and need to wait 5 or 10 seconds for the displayed strength to adjust. From the diagnostics screen, I can move the antenna around and the numbers float around until I stop moving it. I only spent a little while playing with that before bed last night, but I managed to get KRCW 33 up to around 50% strength and viewable. Unfortunately, you can not change channels from the diagnostics screen, so I did not notice until a little while later that this move had cost me all of my VHF channels. Regardless, having a quicker way to measure signals should make the "antenna shuffle" quite a bit more productive.

Rabbit: Regarding a preamp in my scenario... A little bit of reading, it sounds like the main difference between an amp and a preamp is ultimately the quality and the amount of noise that it introduces? Is that correct?

While I had been using a 100' coax when doing my further afield tests, do you think that I would get much out of a preamp in my normal scenario? Right now, I have a 6' coax from the antenna to the FM trap, and a 3' coax from the trap to the tuner.

Assuming this turns out, down the road I would be connecting the antenna to the house wiring, and I very much expect an amp could come into play. But before I spend on amps other than the little ones (that came with the prior two antennas) that I have already been testing with, I wanted to ask.

Thank you!

[rabbit73]

Rabbit: Regarding a preamp in my scenario... A little bit of reading, it sounds like the main difference between an amp and a preamp is ultimately the quality and the amount of noise that it introduces? Is that correct?

Sorry, I have been a little careless with my terminology which has added to your confusion. I have used the terms preamp and amp interchangeably, which isn't very precise.

There are two types of amplifiers in common use for antenna reception.

1. A preamplifier, or preamp, consists of two parts, the amplifier itself which is close to the antenna and designed to be outside, and the power supply or power injector which is inside.

With this setup it is possible to use the same coax for the signal coming down from the antenna AND for the DC power going up to the amplifier without them interfering with each other.

It is desirable for the preamp have a low Noise Figure (NF) so that it adds as little of its own noise that would interfere with the weakest signals, because its noise degrades the SNR of the weak signals. If the SNR falls below 15 dB, the signal drops out as it falls off the "Digital cliff." The NF of the preamp determines the total NF of the system because of its position at the beginning of the signal chain.

2. A distribution amplifier is used inside to feed more than one TV if the signals from the preamp are not strong enough. The NF of the distribution amplifier (DA) should also be low, but it is not as critical as the NF of the preamp. The DA can also be used as a preamp inside as in your case, like the Channel Master 3410.

Update 5/29/2015: Delete 3410 from preamp list on the advice of ADTech. See post 20.

While I had been using a 100' coax when doing my further afield tests, do you think that I would get much out of a preamp in my normal scenario? Right now, I have a 6' coax from the antenna to the FM trap, and a 3' coax from the trap to the tuner.

The 100' coax was making your UHF signals about 6 dB weaker. I think you should let you equipment tell you what improves reception because we haven't yet discovered all the factors that affect it.

You already have a good idea of how strong the signal needs to be. You now need to learn how to use the SNR and uncorrected errors to guide you, no matter what the tvfool report says; I can't be there to help you.

[ADTech]

After testing samples of each, I cannot suggest the CM3410 and its PCT equivalent. They seem to have a noise figure problem below 200-250 MHz.