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Antenna is a deep fringe Weingard with a 7777 preamp on a rotator mounted about 30 agl. Last night when KOVR went bye bye, I changed over to chl 10 and the signal was almost as high as my Sony TV signal meter can go. Click back to KOVR and it dropped by over half.
This is just a case of temperature inversions occurring at inopportune times. When you have this problem with KOVR you should check KTFK. It's on RF 26 right next to KOVR and the antenna is on the same tower. I've found both stations to go up and down in unison. If KOVR is bad I would expect KTFK to be bad too. KXTV is also on the same tower but VHF can act different from UHF even from the same location.

I have the same lack of a back-up CBS station. KION is too unreliable and is subject to interference from KEMO on 32 and KPIX is too weak here to be reliable.

I'm still curious if you have LOS to Walnut Grove because LOS is usually quite reliable reception. The fact that your signals go up and down so much suggests you have at least 1 edge.

Chuck
 

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This is just a case of temperature inversions occurring at inopportune times. When you have this problem with KOVR you should check KTFK. It's on RF 26 right next to KOVR and the antenna is on the same tower. I've found both stations to go up and down in unison. If KOVR is bad I would expect KTFK to be bad too. KXTV is also on the same tower but VHF can act different from UHF even from the same location.

I have the same lack of a back-up CBS station. KION is too unreliable and is subject to interference from KEMO on 32 and KPIX is too weak here to be reliable.

I'm still curious if you have LOS to Walnut Grove because LOS is usually quite reliable reception. The fact that your signals go up and down so much suggests you have at least 1 edge.

Chuck
I'm 35.92 miles not LOS. I have a ridge less than five miles from QTH blocking LOS.
I have a similar issue going towards SF. There I have two ridges, one at about 5 miles and a second higher one at 11 miles. Sutro is 26.17 miles away. I haven't seen too many issues with temp inversions / ducting or sun bore-sight interference.

I do notice any time KOVR goes on their back-up, I lose them.

Back in the analog days, I could pull in channel 12 from Chico without any problem. Based on testing I performed with a VHF radio system years ago, I discovered that for any given power, the digital signal went half the distance that the analog went. We ended up installing portable repeaters in the staff cars to compensate for the loss. The hand held radios only needed to make it to the cars and the higher power radio in the car would reach the base stations. I expected the same thing to happen with HDTV and it appears to be the case. That's why the deep fringe antenna and the preamp just to get what should be a good signal.

Longest "skip" I ever got was when I lived in Pleasant Hill and got an El Paso, Tx station one night. Came in great. Better than any SF station.

Oh Well
 

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I'm 35.92 miles not LOS. I have a ridge less than five miles from QTH blocking LOS.
I have a similar issue going towards SF. There I have two ridges, one at about 5 miles and a second higher one at 11 miles. Sutro is 26.17 miles away. I haven't seen too many issues with temp inversions / ducting or sun bore-sight interference.

I do notice any time KOVR goes on their back-up, I lose them.

Back in the analog days, I could pull in channel 12 from Chico without any problem. Based on testing I performed with a VHF radio system years ago, I discovered that for any given power, the digital signal went half the distance that the analog went. We ended up installing portable repeaters in the staff cars to compensate for the loss. The hand held radios only needed to make it to the cars and the higher power radio in the car would reach the base stations. I expected the same thing to happen with HDTV and it appears to be the case. That's why the deep fringe antenna and the preamp just to get what should be a good signal.

Longest "skip" I ever got was when I lived in Pleasant Hill and got an El Paso, Tx station one night. Came in great. Better than any SF station.

Oh Well

I know there was fading in the analog days too but we just put up with it and tend to forget the times when the signals were not so good. I think the "digital cliff" gives us a distorted sense of what's going on. I still receive a few analog signals here and they vary hugely in quality.

Unfortunately non LOS invites very large swings in signal strength and if your signals are a bit marginal then you'll have problems during bad times.

I don't think the kind of solar interference you mention is possible on UHF or VHF with the relatively low gain antennas and high power transmitters we have. That problem is mostly confined to high gain dishes receiving weak satellite signals.

If you haven't noticed the effects of temperature inversions it's because your signals have enough margin most of the time. I'm sure if you monitored your signals over time with a spectrum analyzer you'd see quite a bit of variation. I've monitored KSBW here and have seen 30 dB or more total swings in signal strength but the station is so strong and low multipath that it never drops out. If I had never made it a point to look at it I'd have never known what was going on.

Chuck
 

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KOVR

Looks like KOVR is on the back-up antenna this morning. It's down about 12 dB in signal strength and the SNR is down too. KTFK is normal strength and so is KXTV both on the same tower.

What happened?

Chuck

Edit: Back to the main antenna at 8:30 am.
 

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What do you consider to be affordable?

Chuck
That's a good question... I think the $600 ones I see on solidsignal are a little pricey for me. I do however like the way a tower looks and wouldn't mind paying around $300 for one. After searching the net all I am really able to find are towers from solidsignal though.
 

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KXTV

The FCC finally approved today the KXTV application to operate a channel 36 low power translator station. Looks like the location is the tower next to their building in Sacramento.

Now the question is will it actually be built?

Chuck
 

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Hi guys I was wondering if anyone here knows an affordable way to purchase or build a 25-30 foot tower. I see they are pretty expensive when purchased through solidsignal. Any thoughts?
If you just need a 25-30 foot-plus cable-supported freestanding mast and not a heavy-duty climbable tower, why not go for a Channel Master 25 or 40 foot telescoping mast?
http://www.channelmasterstore.com/Antenna_Masts_s/42.htm
 

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@Calaveras, nice tower! That has quite the antenna mounted onto it. How tall is your current crank up tower?

It's a 55' crank-up/tilt-over. Image with current antennas attached.

A 33' crank-up self-supporting tower is $2000 - $3000. The least expensive good quality tower is Rohn 25 but it's not self supporting and you have to climb it.

A push-up mast is much cheaper and may very well be good enough for you. It's not self-supporting either.

As soon as you mention self-supporting the price goes way up. Towers can be had from estate sales at low cost or even free but you often have to take them down, transport them, and buy a new base.

Chuck
 

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It's a 55' crank-up/tilt-over. Image with current antennas attached.

A 33' crank-up self-supporting tower is $2000 - $3000. The least expensive good quality tower is Rohn 25 but it's not self supporting and you have to climb it.

A push-up mast is much cheaper and may very well be good enough for you. It's not self-supporting either.

As soon as you mention self-supporting the price goes way up. Towers can be had from estate sales at low cost or even free but you often have to take them down, transport them, and buy a new base.

Chuck
Excellent set up!

I'll keep an eye out for estate sales in my neighborhood. I've actually seen quite a bit of the self supporting type in persons backyards that are being un-utilized. I'm tempted to knock and offer. It would be a pain to have to dig up the concrete base... but in the end I think I would save quite a few dollars doing so.
 

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Telephone Pole Antenna Tower

Have you considered having your local utility install a telephone pole for an antenna tower? It's self-supporting, wind-resistant, does not require tons of concrete, and a hinge and pulley system can be used to raise and lower your antenna mast from the ground. If you want to climb it, you can install pole climbing pegs so you don't need spiked boots and climbing belts.

Convert Telephone Pole To Hinged Antenna Tower
http://www.homesteadingtoday.com/specialty-forums/survival-emergency-preparedness/communications/470978-convert-telephone-pole-hinged-antenna-tower.html

http://www.iw5edi.com/technical-articles/installation-of-the-utility-pole
 

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Have you considered having your local utility install a telephone pole for an antenna tower? It's self-supporting, wind-resistant, does not require tons of concrete, and a hinge and pulley system can be used to raise and lower your antenna mast from the ground. If you want to climb it, you can install pole climbing pegs so you don't need spiked boots and climbing belts.

Convert Telephone Pole To Hinged Antenna Tower
http://www.homesteadingtoday.com/specialty-forums/survival-emergency-preparedness/communications/470978-convert-telephone-pole-hinged-antenna-tower.html

http://www.iw5edi.com/technical-articles/installation-of-the-utility-pole
That's a really good idea. I wonder how much they would charge me. At one point I even was looking at rigid flag poles... but they ended up being pretty expensive too.
 

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That's a really good idea. I wonder how much they would charge me. At one point I even was looking at rigid flag poles... but they ended up being pretty expensive too.
Not sure of PG&E's policy on customer-owned poles, but they will supply and install customer-owned SERVICE poles. PG&E might be able to recommend a private contractor in your area:
http://www.pge.com/includes/docs/pdfs/mybusiness/customerservice/startstop/newconstruction/greenbook/servicerequirements/025055.pdf

There used to be a number of local private electrical utility contractors during the housing building boom in California that would install private poles, but they seem to have disappeared in this state. A Modesto area company can supply and deliver a single utility pole for private use, but you would need to find a local excavating contractor to power auger the post hole and lift and position the pole into the hole.
http://norcalpole.com/index.html

Depending on your land access and pole length, you might need to find someone with compact equipment. It is possible to manually set a utility pole using a gin pole (A-frame) and winch system, but a suitable gin pole may not be readily available to rent.
http://www.ezspotur.com/prod_hdpole.php
https://www.google.com/search?q=pole+erecting+machines
http://www.tngun.com/wp-content/uploads/2013/01/SS0439-Set-Poles-Install-Anchors-and-Guys.pdf
 
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