SF Bay Area - South Bay/Penisnsula

[GaryPen]

Any members located in the SF South Bay area? I'm wondering what people have been doing for their terrestrial reception. What has worked for them, and what hasn't.

Currently, I've got an Antennas Direct DB4 and Winegard HD-6010FM with a CM-7777 preamp, mounted 20ft high, approximately 37 miles from the Sutro tower.

Overall, I get solid reception with all but two stations, KGO (v7 rf7), and KTVU (v2 rf44). I wonder if this can be due to the fact they also simulcast on rf35 and rf48, respectively, from San Jose. I have deleted the simulcast channels from the tuner, as they seemed to be even worse signal strength/quality, most likely due to direction, as they are actually much closer.

I am thinking of upgrading to an 8-bay antenna, probably AntennaCraft U8000, and maybe even change the preamp, probably an AntennaCraft 10G222.

Is anybody else having issues with these two stations?

Does anybody else have any experience with either the U8000 and 10G222? (Or, for that matter, the DB4 and CM7777?)

Thanks.

 

[larrykenney]

Hi Gary... I'm located in San Francisco. I think the reason you're having problems with KGO 7 is that you don't have a VHF antenna. I can't give you a reason for your not receiving KTVU. If you plan to change your antenna I suggest you go with the Winegard HD-7696P. It covers VHF and UHF and has been receiving lots of positive comments on how well it works. It covers channels 7 through 51. You could than turn your DB4 toward the hills above Fremont to get good signals from all of the stations up there - including 1 (42), 2 (48), 7 (35), 14 (51), 36 (36), 48 (49) and 54 (50). You can get a combiner for the two antennas and have just one coax going to your TV. Your CM7777 is still one of the best preamps available, so if it's still working okay, I wouldn't change it. I'm not familiar with the U8000 or 10G222.
Larry

 

[GaryPen]

Actually, I do have a VHF antenna. The HD6010, being an FM antenna, should be capable of picking up rf-7. Plus, I had picked up KGO in the past with only the DB8. I also pick up KNTV 11 (rf12) just fine.

I was wondering if anybody else at similar distances from Sutro were having any issues with those two channels, thinking that maybe it was something going on with those two. But, I'm gonna go back and really check alignment, wiring, and preamp to see if there is something in that signal chain that might be causing the problems.

I doubt very much I will add a yagi or fishbone antenna to the existing setup. But, you did give me a good idea about aiming at Milpitas/Fremont. I could add a 4-bay pointed that way, which should get me the simulcasts of KGO and KTVU at rf 35 and 48. Those towers are only 11 miles away!

Can I use a standard 2-way splitter to combine the two UHF antennas?

 

[Trip]

If I'm not mistaken, the HD6010 looks to be a low-VHF antenna made for FM, while KGO is a high-VHF signal. It's also not a directional antenna, so any multipath interference would not be rejected.

KGO is also further away from you on Mt. Sutro at less power (24 kW) than KNTV on Mt. San Bruno (103 kW).

What TV or receiver are you using? And would you mind posting a TVFool reception report for your address?

- Trip

 

[GaryPen]

All true. But, something is just not right. According to both Antennaweb and TVFool, I should be receiving these channels fairly easily. And, IIRC, I had all the channels when I was testing the Hopper OTA module. And, that was with additional length of temporary coax from the guestroom. So, I will definitely recheck wiring, preamp functionality, and even position, this weekend, to ensure everything is working correctly on my end.

I recently remounted my antenna, adding the HD6010 and a longer mast, after a while of non-use. And, will be re-running the wiring so as to supply both the guest bedroom and the Hopper in the LR. (I used to diplex OTA to my 722, which is not possible with the Hopper.) The TV tuner in the guestroom is the one built in to a Panasonic plasma, circa 2009. Perhaps the Hopper module works better?

 

[FaT Air]

I'd try without the 7777 amplifier as all your signals are healthy(green).

 

[GaryPen]

I'd try without the 7777 amplifier as all your signals are healthy(green).

Thanks. I was thinking that, as well. I was going to try bypassing it as part of the diagnostics, this weekend. I'll do it first!

 

[FaT Air]

If feeding multiple televisions, and a regular splitter results in too much loss, suggest using a distribution amplifier. I've used both the CM3414 and CM3418 models with good results.

 

[GaryPen]

I used to have a 3414, years ago.

What would make a distro amp better than a preamp and splitter for feeding multiple tuners?

I would think it would be best to amplify the signal at the antenna, rather than further down the line, to avoid amplifying noise and such.

 

[FaT Air]

You have good signal (green) so a high gain preamp isn't necessary. And will actually degrade reception caused by what's called overload. Pre-amps can help if your signals are marginal.
Distro amps are designed to distribute a good signal. They have just enough gain to overcome the loss of splitting the signal to more than one 'output'. (Plus a little, usually, only around 3db or so, to each output)
FROM: channelmaster.com - - cm7777.html
This antenna amplifier is a high gain, low noise preamplifier used for weak signal areas to allow a weak signal that is present at the antenna to be amplified to a viewable strength.
Your signals, I don't think. would be considered weak.
The whole WARNING paragraph there is quite informative, without getting technical.
I've 'fixed' many self installed ant/preamp systems by removing the preamp and installing a distro-amp in places with strong signals. (Their 'Returns' that are not defective(??) whoa 99%.)

Try without an amp. Put a splice at the antenna bypassing the amp. Also bypass the power inserter. See what your receptions is then. If good. Add splitter. If degrades too much, replace splitter with distribution amp. Or you may try the 7778 preamp (16db gain vs 30db with the 7777)
Less gain means less chance of overload.

 

[GaryPen]

Thanks. I won't have to splice for testing. I'll use high-quality barrels.
Then, if successful, I'll replace the jumped lengths with new contiguous cable runs.
I'll test a single tuner, first. Then, I'll add additional tuners to see if I lose too much signal, and add an amp, if necessary.
Does that sound like a decent plan?

BTW, What do you recommend to combine the DB4 and 6010HD antennas to a single cable run? Currently, I use the separate UHF and VHF inputs of the preamp.

 

[FaT Air]

Yeah, In my area, two separate inputs were a 'blessing', as the UHF and VHF are in opposite directions. Being your signals levels are good, a regular two way splitter should work just fine, 3db loss should be 'no problem'. If they are mounted on the same pole, I'd just make the coax lengths from splitter to antennas the same length to minimize multipath. If not, experimentation with cable lengths may be necessary.
Here again, a 'test' could be done, to determine if the combining contributes to degradation. Connect one antenna to TV - check reception. Then the other. Then combine them with the splitter.
If overly degraded, might have to use a U/V combiner. examples http://www.amazon.com/dp/B001VLPQ6K/?tag=satell01-20
and http://www.solidsignal.com/pview.asp?p=uvsj

 

[FaT Air]

splice -> barrel, that's what I meant. 'splice' with a barrel.
Soda -> Pop, Porch -> stoop. Depends on where ya come from.

 

[GaryPen]

Thanks for the tips, Fat Air. Removing the preamp definitely helped. KGO (rf7 and rf35) comes in great now! But, I'm still having issues with KTVU (rf44 and rf48).

It's weird because, as you know, the DB4 is a UHF antenna. Yet, I am getting a VHF channel better than a supposedly strong UHF channel. I am receiving both simulcast signals of each station, even though I am pointed NW to Sutro/San Bruno, approx 90+deg off-axis from their secondary transmitters on Monument Peak. I receive KICU (rf36) like gangbusters from Monument Peak. So, I would have thought I'd receive the KTVU signal from there without any issue. OTOH, KTEH (rf50) doesn't come in well from there. No biggie, though, as that is mainly an SD simulcast of KQED.

I'm going to try tweaking the aim a bit tomorrow. I am also going to re-route some cabling, enabling me to shorten some lengths. If that stuff doesn't help, I might try an 8-bay bowtie. I have been intrigued by the AntennaCraft U8000. (and even the U4000 4-bay.)

 

[larrykenney]

I recently remounted my antenna, adding the HD6010 and a longer mast, after a while of non-use. And, will be re-running the wiring so as to supply both the guest bedroom and the Hopper in the LR. (I used to diplex OTA to my 722, which is not possible with the Hopper.) The TV tuner in the guestroom is the one built in to a Panasonic plasma, circa 2009. Perhaps the Hopper module works better?

My Dish OTA Dongle receives weak signals better than any of the other tuners I have. It brings in stations that my TV's show as "No Signal", so that could be the difference between the Panasonic vs the Hopper.

Sorry I can't be of more help than what I already offered. FaT Air seems to be very knowledgeable and is offering you lots of good info. Good luck!

Larry
SF

 

[GaryPen]

Thanks Larry. I have a feeling the dongle will do well, once I get the splitter amp hooked up, and new wiring run.

When I had the it hooked up a while back, it did pretty well, IIRC. I've just been using the guestroom TV for testing now, as I didn't want to run temp cables across the house. I'd rather test it with the correct runs.

 

[FaT Air]

TV antenna installation is more art than science and theory. Once heard a story of someone not getting a station that everyone else was getting. Had erected a 40 ft mast for the antenna. Tried everything 'in the book' but no luck. After trials and tribulations, an 'old timer' told them to move the antenna to only 20 ft. After much consternation, As the 'theory' says 'higher is better', they tried moving the antenna down. It worked, got the station with good signal, go figure.
You may also try moving the antenna fore/aft/left/right. May see differences in just a few inches.

Some theory that does 'hold true' - About the amp:
With your strongest signal being approximately -25dbm, +30 db gain would put the result at +5dbm. The amplifier is only capable of outputting probably -10dbm 'cleanly'. (they used to publish the spec, why do they not today??)
Add all the other powers and the result is even worse. Somewhere near +10dbm.
Looking at these numbers, I wouldn't even consider the 7778 either. Distro amp is the 'only way'.
Have a good day.
FaT Air

 

[GaryPen]

Unfortunately, moving the mast position is not an option, at this point. But, I will experiment with rotation.

Thanks again for all the tips and advice. I'll update my progress at each new phase.

 

[GaryPen]

UPDATE: I rotated the mast a few degrees eastward, and...Voila! I am now getting KTVU and KGO with good steady signals. (Both simulcasts of each.) That original style DB4 is pretty impressive.

I'm still only connected to the one TV in the guestroom. I'll be re-routing cable runs in the attic, adding the splitter, and fishing through the walls to the other locations next week. I'll purchase a CM-3414, just in case. But, I've got a passive 4-way splitter to try first, just in case things work fine without the distro amp. ($30 is $30!)

I'll update again at that time.

 

[GaryPen]

I finally re-routed the cabling in the attic, and fished new cables down the wall into the LR, reducing the total cable length to the home theater, and to the node.
I also pulled some cat6 to the HT and down to the crawlspace, as well. I still have to fish it to the office room, where the router is.
The runs to the master and guest BR's are the same for now. I will add cat6 and another RG6 run for the guestroom, so it'll be easy to swap the Joey to there, when people are staying over.

OTA reception is great on the Hopper and on the guestroom TV. And, FM reception is fantastic on the AVR with HD Radio. I did add the the CM7777 back into the signal path, though.
I think I might also upgrade from the DB4 to an 8-bay, either an A.D. DB8, C.M. 4228HD, A.C. U8000, or maybe even Solid Signal's own brand 8-Bay. (8HDX8X or something.) I'm leaning towards the 4228, as it is especially strong in the low-UHF channels (KRCB is RF23), and also has a good rep for high-VHF. (ABC is rf7 and NBC is RF12 here.)
I'm interested in receiving KRCB, which is approx 70 miles north. Luckily, it's in roughly the same direction as the bulk of my other stations.

Thanks again for all the tips. I'm pretty happy with the way things turned out.