Indoor DTV DXing

[NN2E]

Just for the heck of it I thought I'd do some "indoor DTV DXing." The big antennas are down for repair so I'm now using a Rad-Shack VU-110 suburban VHF/UHF combo antenna, sitting on a pile of boxes, on the second floor of the house, about 15 ft. above ground level, beaming 300 degrees, through the window. Using a Channel Master 7777 pre-amp, a Zenith DTT-901 converter box, and a ProVideo 901B, 9 inch B&W monitor. Let's see what it'll find...

#1-WTCT 17 Marion, IL. 60 mi.
#2-KBSI 22 Cape Girardeau, MO. 70 mi.
#3-WPTY 25 Memphis, TN. 140 mi.
#4-WREG 28 Memphis, TN. 140 mi.
#5-WKNO 29 Memphis, TN. 140 mi.
#6-WLMT 31 Memphis, TN. 140 mi.
#7-WPSD 32 Paducah, KY. 35 mi. (Xmitter located at Monkey's Eyebrow, Ky. No kidding)
#8-WSIL 34 Harrisburg, IL. 55 mi.
#9-WKMU 36 Murray/Mayfield, KY. 10 mi.
#10-WKPD 41 Paducah, KY. 20 mi.
#11-WDKA 50 Paducah, KY. 47 mi. (Xmitter in S. IL.)
#12-WMC 52 Memphis, TN. 140 mi.
#13-KFVS 57 Cape Girardeau, MO. 70 mi.
#14-WHBQ 53 Memphis, TN. 140 mi.
#15-WBBJ 43 Jackson, TN. 84 mi.
#16-KTEJ 20 Jonesboro, AR. 143 mi.
#17-KVTJ 48 Jonesboro, AR. 143 mi.
#18-WTVF 56 Nashville, TN. 100 mi.
#19-WJKT 39 Jackson, TN. 84 mi.
#20-WPXX 51 Memphis, TN. 135 mi.
#21-WKMA 42 Madisonville, KY. 58 mi.
#22-WSMV 10 Nashville, TN. 100 mi.
#23-WEVV 45 Evansville, IN. 90 mi.
#24-WFIE 46 Evansville, IN. 90 mi.
#25-WZTV 15 Nashville, TN. 100 mi.
#26-WLJT 47 Lexington, TN. 78 mi.
#27-KNLC 14 St. Louis, MO. 155 mi.
#28-WNAB 23 Nashville, TN. 100 mi.
#29-WSIU 8 Carbondale, IL. 97 mi.
#30-KPLR 26 St. Louis, MO. 158 mi.
#31-WKRN 27 Nashville, TN. 106 mi.
#32-WHTN 38 Murfreesboro, TN. 125 mi.
#33-WJFB 44 Lebanon, TN. 125 mi.
#34-WMBD 30 Peoria, IL. 269 mi.
#35-WPXS 21 Mt. Vernon,IL. 142mi.
#36-KHBS 21 Ft. Smith, AR. 375 mi. New one. DTV #244
#37-KFSM 18 Ft. Smith, AR.
#38-KLRT 30 Little Rock, AR. 270 mi.
#39-KSDK 35 St. Louis, MO. 160 mi.
#40-WRBU 47 E. St. Louis, IL. 155 mi.
#41-WUSI 19 Olney, IL. 140 mi.
#42-WOAI 58 San Antonio, TX 770 mi.
#43-KYTV 44 Springfield, MO. 250 mi.
#44-KASN 39 Pine Bluff, AR. 270 mi.
#45-KHOG 15 Fayetteville, AR. 320 mi.
#46-KTVT 19 Ft. Worth, TX. 570 mi.
#47-KOET 31 Eufaula, OK. 400 mi. DTV #245
#48-KVDA 38 San Antonio, TX. 770 mi. DTV #246
#49-KTBC 56 Austin, TX. 700 mi.
#50-KBTV 40 Port Arthur, TX. 560 mi. DTV #247
#51-KLJB 49 Davenport, IA. 325 mi. DTV #248
#52-KTVI 43 St. Louis, MO. 160 mi.
#53-KVUE 33 Austin, TX. 700 mi.
#54-KNVA 49 Austin, TX.
#55-WSEC 15 Jacksonville, IL. 210 mi.
#56-KFVS 12 Cape Girardeau, MO. 70 mi. DTV #249 Moved from channel 57.
#57-WTVW 28 Evansville, IN. 102 mi.
#58-WNIN 9 Evansville, IN. DTV #250
#59-WUXP 21 Nashville, TN. 100 mi.
#60-WTWV 23 Memphis, TN. 135 mi. DTV #251 Moved from channel 14.
#61-KPOB 15 Poplar Bluff, MO. 110 mi. DTV #252 Flash cut from analog.
#62-WPGD 33 Hendersonville, TN. 100 mi. DTV #253 Moved from channel 51.
#63-WNKY 16 Bowling Green, KY. 127 mi.

73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

[Robert Grant]

Cool.

You might be surprised to hear that my personal best far DTV tropo was done with an indoor antenna (Chicago DTVs seen in Manistique, MI at 289 miles - 97% of the path over Lake Michigan), in fact, a little RS 15-623 2-bay bowtie (with RDX amplifier).

All the usual multipath issues that hinder local DTV reception with an indoor antenna also affect DTV DX. The same advice still applies. It is best to have the indoor antenna in a window that faces the DX (which means you'll have to move from room to room if you're in the middle of the opening).

Ed, just wondering, what kind of exterior siding does you home have?
wood and vinyl pass RF (with some loss), but brick or aluminum produce considerable loss, with much of the RF entering through any windows the home may have, often causing multipath problems.

Remember that any indoor antenna is really just the feedpoint of a far more complicated antenna system, where house materials act like attenuators, reflectors and directors.

[NN2E]

Good point, Rob.
It's often forgotten that an antenna isn't alone in the world. The antenna system is the antenna plus it's environment. This may explain the results of my indoor antenna DXing experiment. There is a LOT of metal in the antenna's environment. The house has a metal roof and metal trim around the windows. (the siding is vinyl) A large metal barn is in the direction the antenna is pointed. A metal garage and metal roofed sheds are on the property. There is also the house wiring and metal ductwork to consider. Because of all this I suspect that UHF signals are bouncing into the antenna from several directions.
I've thought about "borrowing" the barn to use as a reflector for a UHF curtain array. Might be fun to experiment with.
I can believe that your best DTV tropo was logged with an indoor antenna.... Last Summer I logged KTBU-DT 42 and KTBU 55 Conroe, TX. with the same indoor set-up I'm using now. I think Conroe is about 600 miles from here.
73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

[NN2E]

As of 6-9-09 the indoor antenna has equaled the best DTV UHF tropo, the 7 ft. parabolic has ever gotten, with San Antonio, TX. WOAI and KVDA at 770 miles.
I've been tempted to turn the antenna but I have not. Everything logged with the indoor set-up has been with the antenna pointed towards Cape Girardeau, Mo.

73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

[Robert Grant]

Three letters:

OMG!!!

[ES5NHC]

No matter the setup, keep DXing. I myself have even seen DTV signals from Mikkeli, Finland with a cheapo indoor antenna with a preamp while I live in southeastern part of Estonia.

[antennanut]

I think I need to just set an antenna up in the attic. I'd only need about 25-30 feet of "antenna wire" as I used to call it, so I would use 300 ohm twinlead rather than coax. I think that may be part of my problem with my outdoor setup - 135 feet of mostly horizontal coax running from my TV to the antennas (although it is RG11 with a preamp).

[KA9UVY]

As of 6-9-09 the indoor antenna has equaled the best DTV UHF tropo, the 7 ft. parabolic has ever gotten, with San Antonio, TX. WOAI and KVDA at 770 miles.
I've been tempted to turn the antenna but I have not. Everything logged with the indoor set-up has been with the antenna pointed towards Cape Girardeau, Mo.

73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

Ed, We had an almost 3 day TX,LA,MS. opening here so I am not surprised that you had them even on the indoor setup. The question is what could you have gotten with the BIG antennas?
I captured 38 new stations, most from TX during the event and even could watch Houston DTV at high noon!

Biggest Tropo that way in many years for me.
DTV station count now at 288 !!

[NN2E]

Hi Bob,
Good deal on all the new ones! I sure was wishing I had the big antennas in the air. Had lots of other signal indications but not quite enough to lock. I was tempted to get the parabolic out of the garage and set it up on the porch.
The antenna and tower work is all done. I'm ready to put everything back up so, of course, it's gonna storm for forty days and nights. (I'm hearing thunder as I type this)
Years ago, I was up a tower, installing a repeater antenna, when a storm popped out of the woodwork and lightning hit very close by. I climbed down the tower in record time! Now, if the word "thunderstorm" is in the WX forecast, I stay off of the towers.
Doesn't look like I'll be ready for "The Big Switch."
Murphy is my co-pilot.
73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

[NN2E]

Antennanut,
I've done a bit of research on your co-ax cable run. Not all of the charts are in agreement but it looks like, in the worst case, your line loss could be around 8 db at 700 MHz. (the top of the "new" band, channel 51) You should have enough pre-amp to overcome this loss and still come out ahead.
I wonder if there is another problem. After the lightning damage to your rotor did you...
1- Replace the pre-amp? Lightning killed two of my old 7477 Channel Master pre-amps. They still, sorta, worked after the strikes but they weren't working as they should have.
2- Check all of the connectors? I've seen lightning blow the guts out of a connector yet it still appeared to be OK from the outside.
3- Check for water in the connectors? The original F connector "boots" supplied with most pre-amps / baluns work OK for a while but, eventually, the Sun will cause them to rot / crack / break and then water gets in. I recently did an antenna replacement job (the ice storm killed lots of antennas in Kentucky) and when I checked the original system I found water running out of the co-ax feedline in the customer's basement. (the previous installer didn't waterproof the connections properly) I found water in ALL of the connectors so I had to replace the pre-amp and co-ax in addition to the antenna. I use a good brand of electrical tape to carefully wrap all of the connections. Then I add a layer of RTV silicone sealant. This will last a whole lot longer than the original "boots."
4- Check / replace the baluns / transformers? Lightning can kill the 300 ohm to 75 ohm transformers even though they might look OK. I've also seen them fill full of water if not properly waterproofed.
5- What is your terrain like? Are you on a hill? Down in a valley? Got big trees surrounding the antennas? Terrain makes a BIG difference to VHF / UHF. A friend, who lives about 7 miles east of me, has yet to log a station from Memphis. There's one little hill between his antennas and Memphis and it just kills signals in that direction. I can't hide from the Memphis stations at my location. They're almost pests. Trees, nearby, can get in the way of UHF signals in particular. Worse in the Summer than Winter.
73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

[antennanut]

Ed, thanks for the reply and all of the research!

The RG11 coax and 8-bay were both installed after the lighting strike, so there is new coax and connectors. Prior to that, I was using the Winegard 9095 for UHF and RG6 coax. Both VHF and UHF reception seemed to be the same immediately after the lightning strike for the direction the antennas were pointing so I figured the preamp must have been spared. The rotor's damage seemed to come through the electrical wiring - most of the lightning damage was located in this room, including the breaker to the room in my electrical box that was fried and had to be replaced. The TV the antennas were connected to was fine - in fact, it was the only TV that escaped damage! I also didn't use the boots - I used sealant instead. The balun on the 8-bay was new but the balun on my CM VHF has some age on it.

Perhaps the problem is mostly terrain and surrounding objects? I'm not really in a valley but there are hills all around me within a few miles. My closest obstacle to the south is my neighbor's house, which is slightly more elevated than I am and is probably 150 feet or more from my antennas. That could have some effect on signals coming from Huntsville and Birmingham. To the southwest to the northwest, I am pretty open, with a tree line about 300 feet away, and then hills beyond that a few miles away. North to northeast, there is a tree about 100 feet away, but it doesn't seem to interfere with my Nashville signal strength between summer and winter. Bowling Green has never been a good target for me although it would make the trip if tropo would allow - analog only, as I have yet to see any activity on WBKO from their DTV signal. Northeast to southeast, my house blocks the antennas (live in a subdivision, and although it is a country subdivision with no homeowners association, I still keep the antennas below the peak of the roof as I am the ONLY person with outside antennas). If the antennas were higher things would probably improve, but I would feel pressure from the "eyes of neighbors" bearing down upon me.

Strangely, in a couple of instances, I have better luck with more distant stations that closer ones. I seem to have an easier time with Memphis than I do Jackson (admittedly the towers for the Jackson stations are not very tall). Also, Atlanta sometimes is easier than Chattanooga (especially since February when WZTV-17 Nashville shut off it's analog signal making WPCH Atlanta receivable, and WLJT-11 Lexington shut off, making WXIA Atlanta a lot easier). Heck, since WNPT Nashville moved their DTV from Channel 46, I've been catching Atlanta nightlight on 46.

I want to try an antenna in the attic. My most disappointing reception is of the Huntsville and Jackson stations which are both some 75 miles away. Neither analog nor DTV has come in as well as I think they should. Twinlead might also make a difference for my attic installation, since my previous experience comparing coax to the least shielded type of twinlead on 50' and under runs showed twinlead a clear winner. 135' I know is too long to use twinlead.

Sorry for the long reply!

[NN2E]

Sounds like you've got all of the balun / connector / feedline / pre-amp issues covered.

It does sound like the lightning got in through the electrical service. The rule around here is..."If you want it to work after the storm, you'd better unplug it before the storm."

From what you describe of your surroundings it just might be a terrain issue. I wonder if you've ever looked at a topographic map of your area to compare the terrain to your DXing results.

I can certainly understand about the neighbors. I used to live in a subdivision (30 feet between houses) and you couldn't do a thing without somebody commenting on it.

Twinlead is actually very low loss compared to co-ax. (I've known of people running 1000+ feet of twinlead up to mountaintop antennas) I've always wondered about the shielded type of twinlead, though. My understanding is that twinlead should be spaced a minimum of about an inch away from any metal object. With that in mind it seems kinda funny to wrap the twinlead in a foil jacket. I would think it would increase losses and defeat the purpose of using twinlead.

I'd give the attic antenna a shot. I don't know if it'll outperform the outside antennas but it would be an interesting experiment. I'm kinda surprised with the results of my indoor antenna.


73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

[antennanut]

I haven't looked at a topographic map. Is there a website you know of I can try?

I had a house built in 1998 and had it pre-wired with twinlead. The guy that did it thought I was crazy. I had to buy it - he only carried coax - and even 11 years ago, twinlead was tough to find. But - the guy's workers stapled the twinlead to the studs! I didn't find this out until after I had moved into the house and my reception was horrendous via my antenna. I had that thought about the stapling, and asked him if by chance his guys stapled the twinlead, and he found out they had. I was steamed since the staples essentially shorted it out and rendered it useless. I have some left over from the 70s and I can probably get a decent run into the attic, so I think I'll give the attic antenna a shot in the next couple of weeks.

Man, KTHV-11 in Little Rock sure does look good tonight doing their nightlight. And since tropo is good, I can answer one of your questions from another post - it is Channel 50 in Memphis doing nightlight.

[NN2E]

You might try Google maps. I think you can get some topo maps from them. I'm on dial-up so I can't verify this without dying of old age before the download is complete. I've bought paper copies of topo maps from TVA in the past. I also think you can buy them from the USGS.
Bummer about the stapled twinlead.
Thanks for the clarification on WPXX 50 Memphis nightlight. It wipes out WDKA 50 Paducah at times.
I'm seeing bits of signal from (I think) WMC 5, KAIT 8, WHBQ 13 but not enough to lock, yet.
KFVS 12 (only running 6.8 KW ERP) is so puny I lose them during the day.
73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds

[NN2E]

The indoor DTV experiment has concluded. The big antennas are back in operation.
I'm a bit surprised by how well the UHF signals made it into the indoor antenna. VHF didn't work as well but I still did manage to see some analog E-skip. Never did get any low channel DTV's though. I'd have probably logged a few more had I bothered to turn / move the antenna but I wanted to see what could be had with a fixed direction. 63 stations in 2 months isn't too bad.
73, Ed NN2E
Owner / Operator - Murphy's Law Test Site & Thunderstorm Proving Grounds