Need Advice/Help

[mh272]

Hey everyone, need some advice. I live in a second floor apartment in Delaware.(Brand new, condo type apartments)
I am borrowing a friends AntennasDirect Clearstream 2V, for use indoors (of course), to see if I could get anything.

I am somewhere between 15-20 ft off the ground, my reports:

15FT - http://www.tvfool.com/?option=com_wr...f1f00ed79ba475
20FT - http://www.tvfool.com/?option=com_wr...f1f03078bcf71e

If I point the antenna to Philly, I get:
-----------------------------------------
WCAU 34 (10.1) NBC (Comes in Perfect)
KYW-TV 26 (3.1) CBS (Comes in Perfect)
WPSG-DT 32 (57.1) CW (Comes in Perfect)
WYBE 35 (35.1) Mind (Comes in Perfect)
WPPX-DT 31 (61.1) ION (Comes in Perfect)
WUVP-DT 29 (65.1) Uni (Comes in Perfect),(Don't care for this)
WTVE 25 (51.1) (Comes in Perfect),(Don't care for this)
WGTW-DT 27 (48.1) TBN (Comes in Perfect),(Don't care for this)
WPHL-DT 17 (17.1) MyNine (Comes in Perfect)
WTXF-TV 42 (29.1) Fox (Comes in Perfect)

If I point the antenna to Baltimore, I get:
----------------------------------------------
WMAR-TV 38 (2.1) ABC (Comes in Perfect)
WBAL-TV 11 (11.1) NBC (Comes in Pixilated, breaks, sometimes doesn't tune at all.)
WNUV-DT 40 (54.1) CW (Comes in Perfect)
WJZ-TV 13 (13.1) CBS (Comes in Perfect, but may have to move the antenna slightly sometimes)
WBFF 46 (45.1) Fox (Channel scanned with channel scan, but no picture at all)

As you can see, to get ABC, I have to point to Baltimore because I can't get WPVI-DT 6.1 with this antenna.
Also, when I point to Baltimore, some of the philly stations still tune in, like nbc, cbs, but some don't, like ION and Fox.

What I would like to get from Philly is:

WPVI-DT 6 (6.1) ABC (VHF-LO)
KJWP 2 (2.1) METV (VHF-LO)
WHYY-TV 12 (12.1) PBS (VHF-HI)

Even though I am in an apartment, I am willing to put an outdoor antenna indoors no matter how big or ugly it is. Which one(s) if any should I try? Should I just get myself a C2V?

Could I get greedy and get something like an Antennasdirect DB8e (because of the moveable panels) for UHF? Or would that be stupid to do? I would still need a VHF antenna.

Thanks for any help.

[rabbit73]

Hello, mh272:

I think you are doing very well with an indoor antenna. Some people would by happy if they got as many channels as you are with an outdoor antenna!

There is a big difference between your two tvfool reports; 5 feet makes the signals a lot stronger.

The C2V is doing well for Philly with the real UHF channels listed. It is also doing as well as can be expected for the Baltimore channels that are much weaker.

The C2V has much more gain on UHF, real channels 14-51, from he double loop, than on VHF (2-13), because it only has a dipole (the "V" of C2V). This is why 11 and 13 from Baltimore aren't as good.

As you can see, to get ABC, I have to point to Baltimore because I can't get WPVI-DT 6.1 with this antenna.

The dipole attachment for the C2V isn't long enough for channel 6; it is designed for 7-13. And even if it were long enough for 6 and 2, the noise level (electrical interference) on VHF-Low is often strong enough to wipe out strong signals.

WHYY-TV 12 (12.1) PBS is your weakest VHF-High Philly signal. The dipole doesn't have enough gain for it. You could try adding a preamp to the C2V with an FM trap/filter because you have some strong local FM signals, like WDSD 94.7, 5.8 miles away with a strength of -25.0 dBm. See the attachment.

Even though I am in an apartment, I am willing to put an outdoor antenna indoors no matter how big or ugly it is. Which one(s) if any should I try? Should I just get myself a C2V?

If you want to experiment further than with the C2V, you might consider the Winegard HD7694P which has a little more UHF gain than the C2V, and a lot more VHF-High gain.
http://www.solidsignal.com/pview.asp...enna-(hd7694p)
http://www.skywalker.com/catalog/Manuals/WIN1051.pdf

You could have two antennas, one aimed at Philly, and one aimed at Baltimore, with an A/B switch to change antennas. If your TV can't add a channel after scan like my Sony, you could have the second antenna connected to a separate tuner and feed the output to the A/V input of the TV, so you don't have to rescan every time.

If you want to experiment with the C2V, you could add a preamp, a DIY folded dipole antenna for channel 6, a folded dipole for channel 2, and a HLSJ to combine a VHF-Low antenna with a VHF-High antenna.
http://www.hollandelectronics.com/ca...-Diplexers.pdf



http://en.wikipedia.org/wiki/North_A...on_frequencies

Channel 2 is 54 to 60 MHz, center frequency is 57 MHz.
5540/57 = 97.2 inches dipole length.

Channel 6 is 82 to 88 MHz, center frequency 85 MHz.
5540/85 = 65.2 inches dipole length

Could I get greedy and get something like an Antennasdirect DB8e (because of the moveable panels) for UHF? Or would that be stupid to do? I would still need a VHF antenna.

You could try the DB8E with the panels in different directions. Sometimes it works, sometimes not.

In spite of some glowing reviews, the antenna with two panels, each aimed in a different direction, often doesn't work. When the same signals from each antenna panel reach the combining point, they can interfere with each other if they are not in phase.

No, it wouldn't be stupid. It might be an interesting experiment, but don't get your hopes up.

Originally Posted by ADTech

The DB8e is pretty much as just described. Customers have been asking us for years to include the flexibility of independent aiming of the panels so we tossed the feature in there. When the antenna gets up in the air and the panels are aimed independently, either it will work or it won't. For those customers for whom it works, everyone's happy. If it doesn't then it will be necessary to fall back to the conventional practices of rotors, A-B switches, and the like. There's nothing magical or otherwise about the combiner - it's a very good two port splitter that is about as efficient as we could produce. If it's been treated with pixie dust or otherwise has "special" characteristics that eliminate signal phasing issues, I didn't get told about that. The coaxial cable's length has been optimized for this application.

As the DB8e is a UHF design, its application is going to be somewhat limited by the presence of VHF channels in many markets. It isn't for everyone (no antenna is) but, for those who need its peak boresite gain for "straight-ahead" locations, it's the best thing this side of a parabolic for UHF performance.

Yes, you would still need a VHF antenna.

[mh272]

Rabbit73 thanks for your reply.

Looking at the Winegard HD7694P you mentioned, it has an estimated range of 35 miles on the VHF band and 25 miles on the UHF band. According to my tvfool report I am 55-56 miles away from the broadcast towers. Does distance of an antenna matter?

Also which pre-amp would you recommend? Looking online I have seen a winegard 100 boost, winegard 200 boost, 1 or 2 made by RCA, and I think even antennas direct has one. Thanks for the FM info, will also get a FM trap.

Thanks again!

[ADTech]

Antenna "range" numbers are like the points on a Drew Carey game show.

[rabbit73]

Looking at the Winegard HD7694P you mentioned, it has an estimated range of 35 miles on the VHF band and 25 miles on the UHF band. According to my tvfool report I am 55-56 miles away from the broadcast towers. Does distance of an antenna matter?

I don't pay much attention to the mileage figures. They are a creation of the marketing department, rather than engineering. I go by the strength of the signals and the Noise Margin on your tvfool report. You are certainly welcome to try the larger HD7697 in your apartment. It has a little more gain than the 7694, but it is a lot bigger, and costs twice as much.

HD7694 specs:
•Boom Length: 65"
VHF gain (CH7-13) 8.3 to 9.9 dBd
UHF gain (CH 14-51) 10.4 to 11.5 dBd

HD7697 specs:
•Boom Length: 131.25"
VHF gain (CH 7-13) 10.8 to 12 dBd
UHF gain (CH 14-51) 11.8 to 14.6 dBd

C2V specs:
VHF gain (CH 7-13) 2 to 3 dBi (0 to 1 dBd)
UHF gain (CH 14-51) 10 dBi (8 dBd) average
https://www.antennasdirect.com/cmss_...cSheet_C2_.pdf
https://www.antennasdirect.com/cmss_...heet_C2V_f.pdf

Even without a preamp the 7694 is a little better than the C2V on UHF, and a lot better on VHF, which you need. I'm not comparing mileage, I'm comparing performance.



Interpreting Noise Margin in the TV Fool Report

http://www.aa6g.org/DTV/Reception/tvfool_nm.html

You can add the antenna gain and the preamp gain to the NM figure in the report to improve it, but you must subtract the Noise Figure (NF) of the preamp because it adds its own noise that degrades the SNR (Signal to Noise Ratio) of your weak signals.

The C2V with a preamp would make a smaller package for indoors. The preamps to consider are the Antennas Direct Juice and the RCA TVPRAMP1R. The Juice is very tolerant of overload, but it doesn't have an FM filter. The RCA has an FM filter, is less expensive, but sometimes has quality control problems.

If you are trying for CH 6, some FM filters will mess it up, and some will protect it. See Attachment 2.

Disclaimer: I can't guarantee that this will work. My advice is based on my 73 years of antenna experience, your tvfool report, which is only a computer simulation, and what you have told us.

[mh272]

@ADTech LOL, I get what you are saying

@rabbit73,

Thanks for all your help! I just ordered the HD7694 with the RCA TVPRAMP1R
if the antenna isn't good I will return it.

It's fine if I can't get WPVI (6, 6.1), I will just use WMAR (38, 2.1) for my ABC affiliate since that comes in just fine. Really hoping to get WHYY PBS channel though.

I will let you know by the end of the week or early next week what happened.

Thanks again

[mh272]

Got the 7694 and rca preamp. Had some work/personal related things push back to next week, so I was able to test out the preamp. I haven't done anything with the 7694 yet (I will tonight), but the amp works great with the C2V UHF part, did nothing for VHF. Here are some examples:

Antenna (C2V) pointed to Philly with preamp (FM trap on)
----------------------------------------------------------------
KYW 26 (3.1) CBS - Signal strength from 64 to 100 (Max) - TV calls it MAX
WCAU 34 (10.1) NBC - Signal strength from 78 to 100 (Max)
WPSG 32 (57.1) CW - Signal strength from 66-68 to 100 (Max)
WPPX 31 (61.1) ION - Signal strength from 56 to 82-84

Scanned for channels and nothing else was picked up.


Antenna (C2V) pointed to Baltimore with preamp (FM trap on)
---------------------------------------------------------------------
WMAR 38 (2.1) ABC - Signal strength from 58-60 to 100 (Max)
WNUV 40 (54.1) CW - Signal strength from 44 to 92
WBFF 46 (45.1) Fox - Signal strength from 0 to 78-80 and coming in great

Scanned for channels and it picked up:

WNJS-DT 22 (23.1) PBS - Picture wasn't good until I pointed to about 64 Magnetic

Overall, I am impressed with the RCA preamp.

I had to give back the C2V today, but I will let you know tommorow what happens with the 7694 tomorrow.

[mh272]

Well, no need to wait until tommorow to tell you the results of the Winegard 7694p. And that is, it was not that good.

Tried first without the preamp on, pointed to philly, did a wipe of channels (I can scan channels without wiping out what's there.)

Only a handful of channels were found. CBS, NBC, Mynine and 2 more I don't care for. Only NBC had a picture, everything else didn't.
Then I hooked up the RCA preamp (FM trap on), still pointed at philly, did another channel wipe, and this time it found all the channels in the first post, that the C2V did without a preamp. I had to move the 7694 to find a "sweet" spot so all channels came in good. I found that spot. I never had to do this with the C2V, I just pointed at Philly and it was good. It never found WHYY (PBS) and I did a channel scan at different heights and turned the FM trap off.

Then pointed the 7694 to Baltimore with the RCA preamp (FM trap on), didn't do a channel wipe, just scanned and it found all the channels in the first post except for WBAL-TV 11 (11.1) NBC. Again I had to move the antenna slightly a little bit so to find the "sweet" spot, so all the channels from Baltimore the scanned came in ok. Never had to do this with the C2V, I just pointed at Baltimore and it was good (except for CBS Baltimore, I did have to move the C2V a little before I got a clear picture). It never found WBAL NBC.

I was at this for a few hours, trying different heights (the closer I got to the roof, the worse the signal), FM trap on/off.

So now I am just thinking I should get myself a C2 (without the V). What say you? Just get a C2 and call it a day for UHF? I am still considering a DB8e, just so I don't have to move an antenna to get Baltimore, but like you said earlier, it may not work good with the panels pointed in different directions.

For VHF I am thinking I may never get WHYY here. Anything else I can try for VHF-H?

Thanks for all your help rabbit73

[rabbit73]

Thank you for the report. Sorry to hear that you didn't get everything you hoped for, but you are doing extremely well with an indoor antenna. The aim of the C2 is not as critical as the 7694 because of its wider beamwidth; that's the trade-off between gain and beamwidth. I had hoped that the greater VHF gain of the 7694 would help you with WHYY.

Is WNJS-DT 22 (23.1) PBS good enough for you?

I reviewed this thread, and can't think of any more good ideas for WHYY. It is your weakest desired VHF channel with a 2Edge signal path which means it is doomed to be your least reliable channel.

I investigated the possibility of second harmonic interference from an FM signal. The center frequency of channel 12 is 207 MHz, so there would need to be a strong FM signal around 103.5, but there isn't.

http://www.tvtechnology.com/digital-...ference/202503

It still might be fundamental overload from FM. Your strongest FM signal is WDSD with a signal strength of -25.0 dBm. You could test that theory by inserting one or two HLSJs in series before the preamp, using the high and common ports. The purists would say to put a 75 ohm termination cap on the unused low port.
http://www.hollandelectronics.com/ca...-Diplexers.pdf
http://www.solidsignal.com/pview.asp?p=zhlsj

Sometimes the combined/separate switch of the RCA preamp has a problem making a good contact in the separate position on VHF.

The only other thing I can think of is electrical noise interference on VHF, which is worse than on UHF. It can reduce the SNR of a weak signal making it impossible to receive. I have a VHF-High signal that barely makes it to an SNR of 15 dB which is the minimum for reception before dropout. I have a signal level meter and was able to measure the strength of the signal and the strength of the noise of the adjacent vacant channel to calculate the SNR.

My Sony KDL22L5000 also gives a reading of SNR and errors of OTA 8VSB and cable clear QAM digital signals in the Diagnostics Screen. Here is a bad signal with picture freeze:



Good signal:



My Hauppauge 850 and 950 USB tuners can give a reading of SNR and errors, but the software isn't user-friendly for me.
http://www.hauppauge.com/site/suppor...l_monitor.html



Sometimes the aim of the antenna for maximum signal strength is not the best aim for maximum signal quality, as defined by SNR and errors. I first learned about this with an Apex DT502 converter box, that has dual signal bars, one for signal strength and one for signal quality (the inverse of errors).



I first aimed the antenna for maximum signal strength. Then, when I rotated the antenna slightly to the right, the signal strength was a little less, but there was a big increase in signal quality.

My point is, if you can find a way to measure signal quality, you can optimize the aim of your antenna.

Most of the indoor signals have multiple reflections that make it difficult for the tuner to lock on to the signal. Some locations are so bad that it has been necessary to put the antenna in a shielded enclosure that is open at the front to make the antenna even more directional to reject some of the reflections.
http://www.avsforum.com/forum/25-hdt...l#post21358820

[mh272]

Thanks rabbit, I have a Sony tv as well, and my signal strength screen looks like yours. It's not the ideal PBS channel, but it will have to do. I will try some of the things you suggested. One last question, how can you tell if the fm trap is working on the rca?

Thanks for all your help.

[Stereocraig]

Hey Rabbit.

Not to hijack this thread, but do you know of a shortcut to the Sony signal diagnostics, or do I always need to go through all 11 steps to get there, every time I switch channels?

[rabbit73]

One last question, how can you tell if the fm trap is working on the rca?

The simple test would be to try it in or out on a problem channel. The next level would be to add a HLSJ or 2 in series, between the antenna and the preamp input. I assume you are using the combined all channel input. The next test level up would require lab equipment, but I think your Sony SNR and error readings would tell you a lot with problem channels.

[rabbit73]

Not to hijack this thread, but do you know of a shortcut to the Sony signal diagnostics, or do I always need to go through all 11 steps to get there, every time I switch channels?

Good question; it does take a lot of steps, and I haven't found a shortcut. Different models have it in slightly different places, and the information given by the screen has changed because each design team is able to do it the way they want.

My latest model is the KDL32R400A.
Home > up button > enter for Settings >up button twice for Setup > enter > up button for Product Support > enter >up button for Signal Diagnostics > enter

The screen gives readings for digital OTA 8VSB and for digital clear QAM cable, like this:



The latest version is my favorite because the signal strength range is much greater than the previous models that derived the strength readings from the IF AGC. The strength steps are about one dB each, which is very useful for antenna experiments.

I made a calibration chart giving dBm and dBmV values for the strength readings:



The signal strength range for the KDL22L5000 shown in post # 9 is much less. Once the reading gets to 79, which is about -4 dBmV (-53 dBm) it doesn't go any higher no matter how strong the signal. See Attachment 3.

[mh272]

Thanks for all your helpful information rabbit73

[Stereocraig]

Yes, thank you, Rabbit.

[mh272]

This is just a follow up, I got the DB8e. Works great with one panel pointed at philly and the other at Baltimore. It even picked up WUTB 41 (24.1) with the amp, the C2V with amp never found it.

Great antenna for me

[rabbit73]

Thanks for the good news. You are one of the lucky ones that makes the two panels in different directions work like the marketing guys say it will.