San Francisco, CA - OTA - Page 222

Hi,

My HOA has removed my roof and replaced it with a particle board that is supposed to block heat from coming in the Summer and keep the heat in during the winter. (Metal fibers embedded?)

Anyone heard of this product?

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With my seven (7) tuners I now get very little and they have yet to put the asphalt shingles on top.

So my four Bay Bow Tie UHF antenna on a router and my 2-13 VHF antenna tied up with string in my attic are mostly just dead metal. Worked just fine since ~ 1973.

I have contacted an antenna installer and he told me to get a Channel Master CM-4228HD at Fry's and that he has amps, splitters and so on.

I assume that this is the new one that somehow gets KGO PSID 7, Physical 7. And KNTV on Physical 12)

My worry is that the bottom of the roof (Only location allowed, peak, don't even ask), is North South and Sutro is to the North West. The ideal direction would be at a 45 degree angle but I expect that would be rejected, even the CM-4228HD is already too big but the HOA has allowed two already.

And they have allowed a Single Bay Bow Tie UHF so a homeowner can get KGO.

SHF

A couple of years ago, I'm pretty certain most people felt the 4228 would be unable to receive vhf. It's a uhf antenna. They were wrong. Can the 4228 pick up channels 2-6 well? If an antenna can't, it's considered uhf. As to whether the single classic bowtie can receive vhf, you have to try it before dismissing it. Does the bowtie pick up fm signals as well as a pair of dipoles?

Hi,

Well, it does have the advantage that it is outdoors.



The other two are CM-4228HD, mine will be the third if approved.

Many more to come I suspect, the HOA did not realize what they were getting into. That's why I am trying to move so fast. Three buildings last year, ten (10) this year.

But KGO I would think impossible with that antenna. I think there are other alternatives that are better if only Ch 7 is desired.

If the installer has the time, I will ask him for the real reason a single bow tie was put up.

SHF

At his particular location, with strong signal levels.

Lets factor in the noisy terk amplifier.
A possible KNTV overload signal.
And FM towers 2 miles away.

For VHF ... something like
Terk Antenna ..... -10 Gain/Loss
UHF Bow-tie ........ 0 Gain/Loss


The indoor UHF bow-tie has a short twin-lead cable attached.
Coincidentally, it's about cut the same size as a High-VHF dipole antenna.
The unshielded twin-lead cable itself is the VHF antenna.
If you subtract the amplifier problems of his terk antenna on VHF
This setup may bring better results.
This only works in strong signal areas.
Ben

SFischer1,

I'm thinking of the $4 bowtie as an indoor solution for Vdozer, both uhf and vhf. It will have to be aimed for the various channels of course. I also feel the bowtie to be less vulnerable to multipath versus the Terk amplified antenna.

Keep busy.

Hi,

My Terk amplified antenna, HDTVa has the rabbit ear antennae VHF dipoles which I have never extended. (Note, VHF is not amplified on this antenna!)

Please note that there is a vast difference between South San Francisco and Sunnyvale (Community Center).

The antenna in the picture might well pick up KGO in SSF, but here in the far distance south bay, not.

I added that as a joke, not as an addition to the Vdozer discussion

SHF

[quote=SFischer1;18767367]Hi,

My Terk amplified antenna, HDTVa has the rabbit ear antennae VHF dipoles which I have never extended. (Note, VHF is not amplified on this antenna!)

Fact -check
The terk website says the VHF is amplified 12db . on the HDTVa model.
They do not list the amplifier noise level .... a sign of low quality.
That terk-y antenna itself is the joke.
Products made for a specific retail price point..... Directed by a big box retailer.
"Call China and have them make us a indoor antenna under 60 bucks" ..... says the big box retailers.
Cool design, Slick packaging, Overpriced .. so it must be better.
Terk Technology ? .... What is that ? ..... Sounds cool.

If it doesn't work ..... must have the terk technology.
In all fairness .... The big metal outdoor models they sell DO work.
Don't expect to find those in the big box stores.----They take up too much floor space !
Terk technology ... for all the turkeys. ... Cool

Tied up with string ? 1973 ?
Sounds like possibly they simply damaged it. Or cut the cable.
Or the string gave-out in the roofing demolition / vibration.
I'd Look first .... before spending any money on upgrades.

Hi,

It IS the reroofing!

I was told about the keeping the heat in the Winter and reflecting it in the Summer was the decision point for the special particle board that is the problem.

The HOA manager almost told me to get the outside antenna, she gave me a filled out approved "Request for Architectural Control Alteration" form with the pictures and diagrams that were attached to get the CM4228HD approval for another homeowner.

And the name and phone number of the installer who I have called. So she knows the reroofing is killing OTA antennas in the Attics.

The VHF antenna looks OK, the part I can see. Still pointed at Sutro and string in good shape. But nothing from 7, 12 or FM at all. Cable cannot be looked at but I expect that it is fine.

The UHF antenna on the rotor still works and rotates but I can not get a steady signal on KBCW, the two desired programs are lost. I can tell that it is being shown. KQED (30) seems to be better now but it was not reliable before anyway.

So the roofers did not damage anything except putting the metalized particle board on the roof.

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Actually I would have put a CM4228HD outside long ago if I could and am jumping at the chance to install an outside antenna having been fighting attic weak performing antennas for many years now.

SHF

It is possible to have 1 antenna on the roof serve the whole neighborhood.
Unlike satellite,.... you can split the signal many times.
Share the cost ... with your neighbors , and tie into it.

How many tv outlets you have, determines the amplifier size.
Have an expert ... size the correct amplifier for this.

Hi,

Not as long as Comcast, Dish, AT&T and so have any say. They are collecting big $$$$$ from each of the HOA owners and will not give up that huge sum of money without a huge fight.

With the impending turnoff of OTA HDTV the payback would be negative anyway for trying to do it ourselves. And how could we ever come up with the money to take over the Comcast fiber system to our units?

SHF

You're going to love the 4228. With it pointed up toward Mt. San Bruno and Sutro Tower, you'll probably get good signals for KRCB and KTLN, and maybe even KFTY, too. I bet you no longer have any summer/winter problems like you've had in the past.

Larry
SF

Hi,

I really hope so. The KQED problems in the Winter were delayed until spring, it was about to go back to "good" as it usually is in the summer when the hammer hit the roof. KMTP had all but disappeared.

Now with the new roof on except for the shingles KQED is almost the best station and KMTP is back. Go figure. Old roof was the same as NO roof which I did not expect, I thought that reception would be better with no roof.

Please cross your fingers for me, the HOA has not spoken yet and they could say no if they start to realize how many CM4228HD requests they are going to get. ~ 233 total units, 3 buildings done last year, 10 buildings this year.

And NO rotor.

SHF

Nani, I think that 888 was not suggesting that you would feed the single community antenna into the Comcast fiber network, but would simply add coax in (electrical) parallel. That would be a very sage (and aesthetic) solution to the HOA's problem of antenna bloat!

Also, I agree with Larry's optimism about your likely improved reception with the outdoor 4228 and I don't think that a rotor will be needed for S.F. stations. I don't have/need one in San Carlos and my angular spread between San Bruno and Sutro is much larger than yours in Sunnyvale. But you may not get the KTEH/KICU signals as well as I do off of the "back" of my antenna. OTOH, they may not have the same amount of m.p. interference either...I guess we're going to find out.

We switched to OTA a year ago and have been loving it. We get 100% reception on all channels (I'm in zip 95130) except 7 and 22, which is more like 98%. Unfortunately they tend to drop out at inopportune times (like the US-England soccer game yesterday - DOH!)

When I mounted the antenna, I simply ran a cable to the Comcast connector on the roof and leveraged their existing cabling to and within the house. This is really old stuff actually, involving long black cables (over 100 ft I'm sure) and splitters in the crawlspace going to each room outlet.

My question: Could this be improved?

Someone mentioned cabling earlier. Would it make a significant difference with some newer cabling? Enough to make crawling under the house worthwhile?

Also instead of splitters, is there some kind of "patch panel" device, that would allow me to selectively connect rooms? (Why split the feed to the guest room when nobody's there?)

Regarding amps, I have no power source at the antenna, but I could tap into something near the cable connection on the roof. Would this help deliver better signal to the rooms?

What do you guys recommend?


Karl

Hi,

With all the advertising about 100, 200 and so on channels that's what people want. Plus HBO, ESPN and so on. Oh, and AT&T with their Universe allows an option in addition to Comcast. Most units are set up already. It has been ~ 40 years, that's why new roofs.

The three OTA antennas are in buildings with eighteen (18) units. That's about the ratio for little dishes.

Thus I do not expect every unit to want an OTA antenna, just more than the HOA might be willing to live with. I might be a very rare fish that has an antenna in my attic. A couple of friends side by side might be able to do it.

But should there be a huge number of requests the HOA might balk which is why I want mine to be done quickly, I am in the first of ten buildings this year.

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The rotor I expect will not be needed in the Summer for sure, what I am worried about is KQED in the Winter. Last Winter after Sutro was done was an exception, prior Winters I could not get KQED (30) from any direction at all, sometimes 180 away from the transmitter was the best.

I got a Terk HDTVa indoor antenna and put it on top of a bookshelf to try and get KQED in the Winter. (Second story) It did not work. (It did start to work this Spring.)

It is pointed at Sutro to the North West. KTEH and KICU to the North East come in 5x5 all year long!

Previously I had added an indoor antenna to MyHD's second antenna input for KTEH and KICU. It is pointed to the South East (Remember KTEH and KICU are North East). Again they come in 5x5 all year long (Almost, there are special weather spells that have wiped both KQED and KTEH out at the same time.)

I am keeping my four bay bow tie UHF antenna on a rotor to connect up to a HDHR tuner for KQED in the Winter.

I do not need so many tuners, it just is that I am making so many backup copies to try and get just one. If the CM4228HD works like it should then my original idea of three tuners might now work.

(Want to connect up my new antenna in my attic? Currently 105 degrees F cool. Max has been 130 degrees F)

SHF

Hi,

First, is your antenna pointed in the right direction?

How many drops and splitters? Are there any amps in the system now? Are unused splits terminatated?

An amp can (usually is best) be placed right at the antenna and power fed through the coax cable. The power source needs to be before any splitters unless they are a special type like which will be installed with my new antenna to allow a split in the attic.

Someone will suggest the Channel Master amp to get, I do not have the number handy. I expect one to be installed with my new antenna.

How old is the cable and has it been exposed to the weather? Is the rubber cracked? Perhaps only part needs to be replaced.

I have a CM3418 drop amplifier with eight (8) outlets that might be part of your solution.

http://www.solidsignal.com/pview.asp...mplifiers&sku=

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But your problems sound like the general problems with OTA here in the bay area.

Blame the Weather, temperature inversion, leaves on trees, grass on the hillsides growing and then drying out and so on that many of us must live with. They all change the multipath and make life horrible at just the wrong time. Oh, and any new buildings. Airplanes flying over, there is a website to check.

http://www.avsforum.com/avs-vb/showt...3#post18635793

SHF

I compared a single classic bowtie to a Winegard Freevision on a Zenith 901 converter for rf 7 here. Surprisingly, the results were identical. Both could get around 33% on the signal meter. No A/V was generated by either. Labels on antennas can be confusing.

I'd say yes. Most likely the Comcast internal wiring is not the best, and the more splitters you have the more the signal is being divided and weakened. Remove any splitters you don't need, replace any cable that's been exposed to the weather or been wet.

RF A-B switches can be used in place of splitters as long as you don't need signal on both outputs at the same time. You can select one or the other, but not both.

For the best signal, use RG6 coax, and the shorter the run between the antenna and the TV the better the signal will be. You lose quite a bit of signal in long coax runs.

Here one of my CM4228 antennas output is split. One side with a 60 foot run to the the living room does much better than the other side with a 125 foot run to the computer room and bedroom. I get Sacramento stations with the shorter coax that don't come in with the longer run.

Larry
SF

I've had some bad luck with inexpensive A/B switches with some having high loss on UHF. I don't know what to recommend for a good one.

If you want the lowest loss coax without going to CATV hardline, use RG-11. It's 1.75 dB less loss per 100' at channel 51 than RG-6.

Chuck

Hi,

A piece of the roofing board "fell" into my patio.

Using my Multimeter it read 0.2 ohms along the diagonal.

It looks just like Aluminum Foil glued to the particle board.

Anything my UHF antenna is getting must be bouncing up from below.

Don't you love city hall (HOA) decisions for the people. TV, isn't that going away soon anyway.

SHF

The "gold" A-B switches from Radio Shack seem to work fine. I haven't noticed any appreciable loss though them.

Larry
SF

First signs of Summer... I got a signal on channel 13 today for the first time. It wasn't strong enough to produce a picture, only 13-14 dB SNR. It's interesting that I got it on a bounce with the antenna pointed at 210 degrees. No transmitters in that direction... but I suspect that it's KCBA from Fremont Peak.

Larry
SF

Connecting some old antenna equipment here.
KSBW has locked in ! (That did not happen last year)
They are -7db on the noise margin table of tv fool here.
Right now, I can't tune both KSBW & KVIE at the same time.

Those old channel processors don't work to well with digital tv.

You think that is good? I am currently getting KSBW with 80% signal strength according to my hdhr up here in north santa rosa. I am sure that will not last but it is still cool.

Ha .... And last month 5/14 .... you were talking about poor signals.
We're in a tidal wave of strong right now. Peaks around 9am.

P.S. KSBW's weather channel is better too...... Statewide temps. +

I went with a Winegard with a 14-foot boom length, which fit in the attic without too much trouble. With a 125-foot coax run followed by a 4-way split, it gets good signal for all the stations I care about, and without needing a preamp. Thanks for the advice!

Jim

Good to hear about a successful installation!

Chuck

Article about Sutro Tower Antenna System:

http://www.nxtbook.com/nxtbooks/newb...php?startid=29

Larry
SF

Hi,

Good luck is finding a Channel master CM4228HD at Fry's in the bay area.

The truck never arrived Monday and there is no ETA!

I did a Hail Mary and drive up to Fry's Roseville where they had seven (Now six or less).

Coupling a discussion with a manager at Fry's Sunnyvale with what I heard on the "PBS News hour the problem is with the Banks not making loans to good companies.

So Channel Master cannot get the money to buy the metal to build the antennas.

The program also said that companies are only hiring persons who ALREADY have jobs.

Economy getting better? I think not.

SHF

P.S. I needed to take my van out for a long run to see if it was ready to go camping to "Happy Camp, CA". It is not, front end alignment needed!