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Broadcast TV Transition (Repack)

M

MJH

I live on Raft Island in the South Sound. I installed an Antennas Direct DB4 antenna in 2009 on my roof, about 30-40' above ground level...it has worked fine until last year when the Repack started. I was able to contact KOMO engineering and understand that they had problems with their new antenna install. Using GPS I am 26 miles (much of it over water) on a heading of 020 magnetic degrees from the major station towers of ABC, NBC, and CBS which are very close together. As Repack has been completed I have gone to my roof three times trying to improve my reception to no avail. I receive NBC (5) the best, CBS (7) is very poor, but nothing on ABC (4). YES, I have retuned my TV tuner many times and have tested the preamp, it is working.

My understanding is that Repack was to open more frequencies for cell phones without any loss of TV reception...that has not worked for me and others, I'm sure, in the South Sound. I am trying to understand this loss before buying a new antenna and giving that a try. What am I missing on this loss of reception with Repack?

Thank you for your input.
 
Your problem is that your actually down in on a hole. With Raft Island only at 100' elevation there are hills like Swede Hill at 300' and other location close to 350' in the way. You are not line of sight. Does not matter how much of the signal travels over water if there are 300-350 foot hills in the way.

I'm on Vashon Island and had a similar situation at my dads house. He is at 300' elevation with a 390' hill in the way. He is also closer to Queen Anne though. I had to install the largest Winegard antenna to improve reception. Winegard HD8200U is around $135 on Amazon and longer than a small car (15' if I remember) it's a beast but pulls in the signal.

All the antenna specifications are for line of sight. I suspect the TV signals are just shooting over you. Also it's not so much the displayed channel number as much as it is the actual RF frequency/channel they are transmitting on. I would look at the actual RF frequency of the stations you want to pull in and get an antenna that has strong gain on that area. I will admit that CH4 was the one challenging station for my dads house. My step mom likes to watch Jeopardy.

Other things to consider, do you have tall trees close in, 10-300' from the antenna. That can dampen the RF. Had to adjust the weinguard pointing 3 times before CH4 was solid at my dads house. Not saying a larger antenna will be the silver bullet but something to consider.
 
xmtrland










xmtrland reply: How do you explain the reception change from before Repack...it was good before for many years? Was it all just a coincidence? I find that hard to believe. Yes, there are trees and they do continue to grow, but again, all this change in so little time and in conjunction with Repack happening I somehow think they are related. Also, the Seattle stations have not been very forthright or transparent on this issue, technically speaking. I'm not trying to be a conspiracy freak here, just trying to understand the science that caused my drastic change in reception over such a short period of time.
 
KUSE-LD virtual Ch. 46 started coming in here at my location in Bremerton after the re-pack. I'm glad they carry Buzzr! on 46.5 now.
 
Another update...I contacted Antennas Direct last week to discuss a possible replacement antenna, the Clear Stream Max. I spoke to Randy and, after telling him I bought my present antenna (DB4) from them, he told me the old antenna was better than the new one I was looking into (he is reluctant to sell me a new antenna that may not help). This led to a broader discuss of my situation and advice to test my preamp and possibly raising or lowering the antenna on the present pole. I did test the preamp as he advised and lost all but one nearby station, yes it works. We also confirmed that my cable from the antenna was good but could be shortened. Yesterday I retuned the TV once again and was able to get two stations I had prior to Repack, KONG and KWPX but still no reception for KOMO or KIRO...the on and off again reception tells me stations are still working on improving after Repack. So the mystery remains as to why I get KING so well and nothing on KOMO or reliably from KIRO, yet they are in close proximity to each other; that fact makes me leery in buying a new antenna with the same result.
 
MJH said:
Another update...I contacted Antennas Direct last week to discuss a possible replacement antenna, the Clear Stream Max. I spoke to Randy and, after telling him I bought my present antenna (DB4) from them, he told me the old antenna was better than the new one I was looking into (he is reluctant to sell me a new antenna that may not help). This led to a broader discuss of my situation and advice to test my preamp and possibly raising or lowering the antenna on the present pole. I did test the preamp as he advised and lost all but one nearby station, yes it works. We also confirmed that my cable from the antenna was good but could be shortened. Yesterday I retuned the TV once again and was able to get two stations I had prior to Repack, KONG and KWPX but still no reception for KOMO or KIRO...the on and off again reception tells me stations are still working on improving after Repack. So the mystery remains as to why I get KING so well and nothing on KOMO or reliably from KIRO, yet they are in close proximity to each other; that fact makes me leery in buying a new antenna with the same result.
Click to expand...

KOMO and KIRO are North side of QA hill.
 
Another update.

Here is information I got from Wikipedia:
Station, tower coordinates, transmit power, HAAT (Height Above Average Terrain)

KING:47-37-54N, 122-21-03W, 715W, 761' HAAT
KOMO: 47-37-55N, 122-21-14W, 1000W, 850' HAAT
KIRO: 47-37-58.9N, 122-21-23.9W, 715W, 843' HAAT

Plotting with my navigational software KOMO (absolutely no reception) is a 262.4M/759.5' distance from KING (very good reception). KIRO (sometimes good, other times poor) is a 273.9M/1,513' distance from KING. A terrain chart shows all three stations being within four feet total height above ground of each other.

KIRO-TV reception has improved over the past week.
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 
MJH said:
Another update.

Here is information I got from Wikipedia:
Station, tower coordinates, transmit power, HAAT (Height Above Average Terrain)

KING:47-37-54N, 122-21-03W, 715W, 761' HAAT
KOMO: 47-37-55N, 122-21-14W, 1000W, 850' HAAT
KIRO: 47-37-58.9N, 122-21-23.9W, 715W, 843' HAAT

Plotting with my navigational software KOMO (absolutely no reception) is a 262.4M/759.5' distance from KING (very good reception). KIRO (sometimes good, other times poor) is a 273.9M/1,513' distance from KING. A terrain chart shows all three stations being within four feet total height above ground of each other.

KIRO-TV reception has improved over the past week.
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Click to expand...

At your distance it has little to do with height difference between the three stations, and more your look angle from the receive antenna to the transmit antenna. If you have several hills in the way, terrain is creating multipath to your receiver, not low signal. DTV reception is hampered by multipath. Using a preamplifier will only make the multipath effects worse.
 
Here is a tip. Look at their ERP. They are not the same. I would compare ERP versus coordinates of three tower on the same hill in a row.
 
xmtrland said:
Here is a tip. Look at their ERP. They are not the same. I would compare ERP versus coordinates of three tower on the same hill in a row.
Click to expand...

When it comes to DTV, ERP has little to do with reception, especially as close as this person is. His problem is multipath caused by terrain, pure and simple.

The confusion has always been, that the "signal level" metering on DTV sets doesn't indicate signal level or received field strength, but signal quality. Excessive multipath looks the same to TV as a low signal. If he's running a high gain receive antenna, that's just going to increase the number of reflected signals and thus multipath. Adding an amplifier makes it even worse, because the reflections are being amplified, arriving at different time constants, nulling out the direct signal. Amplifiers will also increase noise floor, which is also destructive to DTV reception.

Back in 2009 when the transition was happening nationwide, I used to get calls and E-mails all the time from people five miles away from QA Hill, complaining that no matter how high of gain antenna they install, they can't see KOMO. Some of them were floored when I suggested they disconnect their antenna coax and insert an un-bent paper clip into the F-connector. For those who kept trying high gain amps and antennas, they were amazed the paperclip worked the best.
 
I appreciate everyone's input. Overall my reception has improved over the last month, particularly KIRO (7), at times but still nothing on KOMO. Reception on others is hit and miss, someday very good other days nothing.

Regarding multipath, how do you explain the total loss of KOMO which was very good before REPACK and absolutely nothing now? I didn't seem to have any multipath interference before REPACK and the terrain hasn't suddenly changed.
 
The causes with multipath vary with frequency. Something locally causing a reflection on Channel 30, may not have the same effect on channel 24. If you have several hills between you and Queen Anne Hill, you're experiencing multipath. KOMO is licensed at 915kW ERP. If you can't receive them at 20 miles away, there is a problem with your installation.
 
Other posters are absolutely correct. I have family in the same general area as you, and they've experienced similar issues. I popped Raft Island into tvfool.com, and it seems like KIRO, KING, and KOMO are definitely problematic signals in your specific area. Looking as a signal analysis, you can glean a lot of information by looking at the "path" column. If you see "1 Edge" or "2 Edge," you might run into trouble. 1 Edge and 2 Edge indicate that you've got land masses in between your antenna and the transmitter site. For Raft Island in particular, you've got a hill just northeast of your location near Rosedale Avenue that likely is causing your problem. I certainly have had the same issues that you have experienced.
 
I have used tvfool.com and AntennaWeb.org.

As I stated in my initial post I had good reception since 2009 when I installed my present antenna. Then reception markedly changed during REPACK. My verbal contact with KOMO revealed they were having antenna problems but it only got worse to the point now I get absolutely NOTHING. Before REPACK=OK; After REPACK=Nothing. I see a relationship there.
 
MJH said:
I have used tvfool.com and AntennaWeb.org.

As I stated in my initial post I had good reception since 2009 when I installed my present antenna. Then reception markedly changed during REPACK. My verbal contact with KOMO revealed they were having antenna problems but it only got worse to the point now I get absolutely NOTHING. Before REPACK=OK; After REPACK=Nothing. I see a relationship there.
Click to expand...
I can see why that would be frustrating. I think Kelly gave you the best answer by far on this one. KOMO is operating at the highest HAAT and ERP, therefore there is no other explanation for what you are experiencing other than some sort of multipath effect that happens to be more pronounced on channel 30. You asked specifically about pre-repack versus post-repack. KOMO was transmitting on channel 38 immediately after the DTV transition. For whatever reason, post-repack channel 30 is not as immune to multipath interference.
 
Another Update: I am now periodically turning my TV on to see what the reception is like at various times throughout the day. KOMO (4) remains totally nothing. Within the past 2-3 weeks NBC (5) has gone from my most reliable Seattle station to a not useable station most of the time while periodically great. CBS (7) remains not useable most of the time. Overall, I get the best receptions during the day for NBC and CBS but I generally don't care for daytime programming, KOMO still nothing. So, I am now effectively locked out of Seattle's major TV stations most of the time; this all due to REPACK.
 
Sorry to hear that your situation hasn't improved. I've experienced similar results at my house, which is in the same general direction as you. KOMO actually is one of my more reliable stations, but there are certain times of day where the signal degrades significantly. My most reliable stations are KOMO, KSTW, KCPQ, KTBN, KBTC, and KWPX. KIRO, KFFV, and KUNS can be spotty, but they can be watchable depending on the time of day. Nothing at all out of KING, KONG, or KZJO.
 
UPDATE: I eventually ordered a new antenna, a Clearstream Max 4 UHF/VHF (C4MVJ1) in early April 2021. My choice was influenced by my neighbor who had just installed one and said he had good reception except for CBS (7). As my home is higher up the hill from him (he is at water level) he thought my reception would be better. Reception did not improve dramatically and reflectors were later added which made a very big difference but still far from what I was after. The antenna with reflectors received KOMO (ABC) very well but worsened for KING (NBC) due to the thin angle required for KOMO and I still could not pickup KIRO (CBS) at all. I do get most of the secondary networks but don't use them much. I was not completely satisfied.

After weeks of testing and conversation with the technical experts I have ordered a different antenna, an Antennas Direct DB8-E, and will give that a try. It is a much bigger antenna with two independent panels, a higher gain, and narrower beam angles.
 
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