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Discussion Starter #1 (Edited by Moderator)
The wife wants a better signal. Especially ch 7 ABC
Current setup. Is an old beat up Radio Shack VU-190XR at 28 ft to clear the trees.
RCA TVPUAMP1R on the mask. 60ft good Belden RG6 to a two way splitter then about 30 ft each way.

The Antenna I had so I put it up to see what i could get and it is better than I expected.
I get most the Mt wilson channels with dropouts, More drops on wind or rain.
I need to get ch 7 better (Hi VHF per tvfool).

Looking at the tvfool map looks like i am line of sight just missing the mountains.
Ch 12 may be an overload problem.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=f1f0ec11e0e54d

I tried an old radio shack adjustable gain amp I had in place of the splitter and it does not help.
Then i installed the RCA pre amp and got a little improvement.

What antenna should I go with a Wineguard HD7698P ? What about a Antennacraft U8000 or Channelmaster extrementenna80? I never used one of the BBQ grill looking antennas.

I was thinking if after installing a new antenna if ch7 is still a problem. Building a CH7 only antenna for the VHF input of the RCA amp.

Thanks a bunch everyone.
 

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Please PM Dr. Don with your TV Fool link so he can add it. There is additional information from the link not available from just the image. I'd like to take a look at your terrain path plot for a typical Mt. Wilson station.

You should run your FM Fool report and post that image so we can see if you might be having FM interference to high VHF. Links don't work with FM Fool.
 

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Discussion Starter #3
Please PM Dr. Don with your TV Fool link so he can add it. There is additional information from the link not available from just the image. I'd like to take a look at your terrain path plot for a typical Mt. Wilson station.

You should run your FM Fool report and post that image so we can see if you might be having FM interference to high VHF. Links don't work with FM Fool.
Thank you I will do that.
Ron
 

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Link added to first post.
 

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There are two possible problems with ABC on CH 7.

The Radio Shack VU-190XR might not be performing as well as when it was new.

The RCA preamp has a history of problems with the separate/combined switch, especially when in the separate position VHF doesn't make good contact. Sometimes it is necessary to use a UVSJ to combine separate VHF and UHF antennas and connect the common output to the combined input of the preamp.
Ch 12 may be an overload problem.
I doubt it; it's close, but it's only a 3 kW low power translator.
RCA TVPUAMP1R on the mask. 60ft good Belden RG6 to a two way splitter then about 30 ft each way.
Where are the splitter and power injector located? Like this?

ANT > 60ft coax > pwr injector > splitter to 2 TVs
should I go with a Wineguard HD7698P ?
Good choice, aimed at 301 degrees magnetic. Try it without the preamp first.

You have some strong FM signals; an FM trap would be a good idea. See the attachment.
 

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Is K12PO, translator for KUSI in San Diego, even on the air, analog or digital? They were last issued an authorization is 2011 for digital operation, but they've never filed an LTC application indicating completion.
 

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I tried an old radio shack adjustable gain amp I had in place of the splitter and it does not help.
Then i installed the RCA pre amp and got a little improvement.
What type of Radio Shack amplifier was it? I think I may have just had the same problem... I was using the Radio Shack adjustable gain preamp model 15-321, and it's a piece of crap that belongs in the garbage. It made my signals worse. When I attached it, I lost 5 channels. I also purchased the RCA preamp and noticed improvement. It showed very minimal overload, and I live in an area where this is a problem. You could use separate UHF and VHF antennas and simply combine them with a combiner/diplexer. If you do that, then there are a lot of options. Or you could use a combination antenna like an HBU33, HBU44, or HBU55.
 

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If in your shoes, I would first replace the RS antenna.

I suggest a Y10-7-13 for VHF & HBD91X(or similar)for UHF.

The 7698 would be a good choice for a combo antenna, but I much prefer separates for 1 & 2 edge signals, especially at those distances.

The RCA preamp you have is a good choice.
 

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Discussion Starter #9
If in your shoes, I would first replace the RS antenna.

I suggest a Y10-7-13 for VHF & HBD91X(or similar)for UHF.

The 7698 would be a good choice for a combo antenna, but I much prefer separates for 1 & 2 edge signals, especially at those distances.

The RCA preamp you have is a good choice.
Thanks for the advise everyone

So it looks like I should use a HD7698P or use separates. If i use separates can i mount them on the same mask or do they need to go side by side. I assume ether way they need to be out of each others bandwidth.

Do i have better gain with separates?

Everything I do turns in to a project!
 

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Same mast, one over the other.

The RCA preamp has a history of problems with the separate/combined antenna switch; sometimes it doesn't make good contact with the VHF antenna in the separate position. The workaround is to connect the two antennas together with a UVSJ, and connect the common output terminal of the UVSJ to the combined input of the RCA preamp.
Do i have better gain with separates?
Pretty much the same unless you can find the hard to locate Y10-7-13; the Y5-7-13 is easier to find.
Everything I do turns in to a project!
Yes, and every project takes longer than we thought it would. And every time we go on vacation, we think we have taken enough money, but we always run short.:)
 

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Pretty much the same unless you can find the hard to locate Y10-7-13; the Y5-7-13 is easier to find.

This has become a real problem for anyone needing a good high VHF antenna. There are several choices for a high gain UHF antenna but none for high VHF. The manufacturers are ignoring high VHF but almost everyone needs a high VHF antenna equivalent to their UHF antenna. Anyone in a fringe area is SOL unless they're willing to build something.

Some manufacturer should offer an antenna like in my image below. I'm currently running a extended test on this 22 element LPDA on an 18' boom. It seems to be equivalent to the pair of 12 elements seen in my avatar. It's easier to install than stacked antennas and there's no combining issues.
 

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How many driven elements does it have?
Interesting question. Chuck is more qualified to answer, but I'll try:

All 22 elements of his LPDA can be considered as "driven" elements.

https://www.google.com/?gws_rd=ssl#q=LPDA+antenna

http://en.wikipedia.org/wiki/Log-periodic_antenna
The LPDA normally consists of a series of dipoles known as "elements" positioned along a support boom lying along the antenna axis.

Every element in the LPDA design is "active", that is, connected electrically to the feedline along with the other elements, though at any one frequency most of the elements draw little current from it.
 

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+1 VERY NICE!! Great quality photo too.

How many driven elements does it have?

Thanks! They're all driven but a better way to look at it is how many elements are active on any frequency? Based on gain it acts like a 4 to 5 element yagi on any frequency.

I've taken photos of the antennas so many times I know where to stand and what time of the day for the best picture. :)
 

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Calaveras: On your "My DTV Page", we can see the design details for your Hi-VHF 12-El LPDA pair, which appear to be a conventional Tau/Sigma type design. Which DOS based LPDA Design program did you use???

Can you provide similar design details for the Monster Hi-VHF 22-El LPDA, incl. details on how the Boom is constructed to support such a long 18-ft length, while also providing the requisite Characteristic Impedance???
 
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