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In Stockton, CA I currently receive all the Sacramento stations, digital and analog. However my antenna a 21 year old combo 8 foot VHF/UHF type has problems receiving the S.F. Bay Area digital stations which are about 65 aerial miles away. Roof and mast/rotor are about 55 feet in height. Depending on weather I can pull in 2.1, 4.1, and sometimes 7.1, but the signal is not dependable.


A week ago I substituted the big RS VU-210 but it didn't increase the signal sufficiently and added much more multi-path.


I'm now considering either the 19 foot Jerrold Delhi or the Channel Master 3671 (14.4 feet long).

I wouldn't mind springing for a Titan 2 preamp but am afraid with it I'd overload all my already strong Sacramento stations. Any recommendations?
 

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If the preamp is not mast-mounted you could get a splitter and feed your unamplified antenna signal directly to one "antenna in" connector on your receiver and feed the other splitter output to the input of the preamp. The preamp output can then be fed to the other "antenna in" (they're usually labeled "ANTENNA A" and "ANTENNA B"). Then select unamplified vs. amplified signal by selecting "A" or "B" antenna inputs on the receiver.


If you need a non-mast mounted amplifier for this, the Radio Shack 15-1113C works well.


If you feel that you must use an outdoor, mast-mounted preamp, use an outdoor splitter and take the antenna balun output and feed one side to the preamp and it's coax downlead and feed the other side of the outdoor splitter to a seperate direct downlead. Feed each of the two downleads to one or other of the two antenna inputs on your receiver.


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HiDefDave
 

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I also live in Stockton and have a VU-120 and mast mounted amp(an amp Radio Shack had on clearance for $17.95) on my chimney with a 6-foot mast. I'm able to get 4,5,7,9,36, and 44 very reliably. I've had issues though, getting channel 2 from Oakland.


It's been great being able to receive the bay-area stations, especially since KOVR13 our CBS affiliate has not been throwing the switch on HD lately.


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Jarred
http://www.jarredinthehouse.com
 

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A excellent all channel antenna is the Winegard 8200. I have that antenna and a Winegard 8275 preamp. I live in a valley behind hills in the Los Angeles area and it receives all 9 LA digital channels. Eight of the channels are solid the other I receive 90% of the time.


Since the one channel that was not 100% was KCBS, I added a CM4248 and CM7775 preamp on the mast. These were highly recommended as the best UHF antenna/preamp on other threads. However they only get KCBS 50% of the time. Thus in my experience the Winegard 8200/8275 is the best, and it is all channels.


Rick R
 

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Patrick,


Good comments overall. But you can no longer recognize log-periodics by the shape. I used to go by that too, as I once owned a big Jerrold. The new Delhi's look like yagis with elements at 90 degrees. They still are tapered shorter toward the front, and all elements are active ie: wired to a harness, except 1 reflector. (The UHF portion is a yagi type with directors.)


One other point: You definitely can add directors to a yagi, and get exactly what you mention: more directivity and more gain. Most antenna books describe this. I found it worked great with my Channel Master 4248's and made them usable at my location with heavy multipath.

 

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jhe,


On the 4248, all the directors are the same length and spaced the same distance, so adding directors would be easy. One antennas like the Blake, the directors are in different length groups and the spacing varies along the boom. How can you determine what size and spacing to use?


I would like to build some channel specific antennas (yagi) if I can find a program that is easy to use and makes sense. Most are written for ham radios.


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-Glenn
 

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I'm trying to pickup the LA UPN affiliate's DTV broadcast (channel 66) from San Diego. Currently I can get a 5% consistant signal strength (peaking to 25% occasionally) on my HTPC's HiPix card with the following antenna configuration:


Antenna: Channel Master CHM-4228 ( http://www.channelmaster.com/pages/u1.htm ) on a 12' pole on my chimney


Pre-Amp: Winegard AP-4700 ( http://www.winegard.com/products/acc...cessories.html )


So where do I go from here? A couple of neighbors have 40' masts on their roofs, should I just walk over and ask if they can get channel 66? Because it looks like I have a good antenna, maybe more height would do it for me.


Also, is it possible to "add directors" to this antenna?


-MM


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Mike
 

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The antenna issue is really hugely dependant upon location as you already understand.


I prefer a Yagi-style antenna (perpendicular reflectors) to the log periodic style (the RS fish scale look) as they tend to try to be less all inclusive. All-inclusive UHF-VHF antenna are a major compromise IN SOME INSTANCES.


That is, if you really want to nail a particular frequency you can NAIL it by purchasing a yagi style tuned to that frequency. Winegard, Channel Master, Antennacraft, Blonder Tongue and Jerrold are very long time manufactures of antennas. They have history and engineering behind them versus the marketing clout of RS.


Some of the RS gear works fine, let's not get defensive about one person's choice if it works for them. I've just found that when there are unique issues the all in one antennas don't perform as well as others.


When you are having site specific issue you need to move into the next level and fine tune your solution. Adding reflectors is not scientific, in fact it makes matters worse. Thus longer booms may not be the solution.


Higher gain, and more directionality may be the path to consider. Or, multiple antenna with one or more specifically tuned to the problem direction or frequency.


The SF channels are UHF and do not require huge antennas. That is, they do not require giant VHF arrays - what they may require is a high gain UHF unit working with the existing VHF unit to meet all of your reception needs.


A preamp will work if there is usable signal to begin with, it is not a panacea.


The suggestion to utilize a split feed is a good one. Consider adding one small, directional UHF to this mix and you can thus cover multiple directions without a rotor.


regards,


patrick
 

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jhe - so the distinction is now blurred between logarithmic and yagi? Great. No wonder there is so much crap sold and then mediocre results attained.


The highest gain UHF antenna (of practical size) I ever personally tested or used was known as the Hovermann. It looked like a four bay bow tie without the screen. Odd looking little hummer and it just creamed the yagi and corner reflector units over most of the UHF band. The giant parabolic UHF antennas which once dotted the countryside remain the single highest gain UHF devices ever designed. Granted they are butt ugly, but they easily schlep UHF from 100 or more miles. Try that with an all-in-one log periodic nee yagi. If you have severe UHF issues, and can lobby your neighbors into looking at your 50" parabolic, you will put the issue to rest.


GlennL - I suspect you can adapt the formula used for HAM antenna to design frequency-specific UHF-VHF size, spacing and orientation. In fact the television spectrum is pretty easy to determine with half and quarter wavelengths.


You must be a metalworker or otherwise have the ability to craft aluminum or why would you even want to muck with this? They are available prebuilt as you probably know. I might try UHF but building a tuned VHF unit is beyond the scope of my meagre machining abilities.

regards,


patrick

 

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Weird, last night I got up to a 60% signal strength from KCOP out of LA on ATSC channel 66 (up from a typical 5% during the day).


So I'm wondering, did the station turn up their signal strength for prime time or was it some external force such as the night-time fog that creeps in along the coast here in Southern California?


-MM


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Mike
 

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Oh, BTW, does anyone in SoCal have one of the "giant parabolic UHF antennas" for sale? I don't think Channel Master is making one anymore.


-MM


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Mike
 

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Patrick,


Yes, I am a metal fabricator and Mechanical Engineer. I have tested just about every popular antenna from my location, including the big CM parabolic.


The order from best to worst, so far, is:


1 My custom built antenna

2 Blake JBX21WB

3 CM 4248 yagi

4 Winegard 9085 Yagi

5 CM 4251 parascope

6 CM 4228 8-bay

7 CM 4221 4-bay

8 Winegard 8800 8-bay


I started a thread here: http://www.avsforum.com/ubb/Forum11/HTML/013407.html

you will find results on page 1 and 2 for the above antennas and on page 4 is a comparison of my antenna to the Blake.


I don't think the 4251 worked very well at all, especially for local channels. Last night I was getting a solid 93-94% signal on CBS, ABC, WB, FOX from San Diego over 130 miles away with my custom.


I want to try and get some local channels that are giving me problems. Maybe a single channel antenna could work better.


I also tried adding about 4' length plus 7-8 elements to my custom, but it did not make an improvement. My custom is somewhat like the Blake with random spacing on the quad elements. I spaced the extra elements based on the spacing near the end of existing antenna.


If you have seen some software for yaqi that is easy to use, I'd be interested. The "yagi optimizer" is difficult and slow. Or even a good book.



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-Glenn


[This message has been edited by Glenn_L (edited 10-11-2001).]
 

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Glenn-

I appreciate your experience w/all of the above-referenced antennas...I have been strongly considering the CA-(series) Winegards, e.g. CA-9085, or the biggest in that series 9095. Did you experiment w/ either, and if so, could you comment on their performance, please? I know the 9095 is (1)big, and (2)extremely DIRECTIONAL. Thanks!
 

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I edited my post above after checking my results, I was only going by memory when I posted from work.


wolv,

You will see that the 9085 did better than most. I think Winegard antennas are built really well and will last for a long time, but there are other antennas that work better in tough locations. Check page 1-2 in above link.


The 9095 having more elements should work better over longer distances.


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-Glenn
 

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GlennL - great stuff on your link. Methodical and solid. Thanks a bunch for posting the previous results of your work.


I do have such a book but I need to dig it out. If I succeed I'll ping you.


regards,


patrick
 

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I have a CM4251 Parascope(7777 amp) installed on the 2nd floor unfinished room. I am able to pull in all of the Raleigh stations which are about 60 some odd miles away. The room is on the east side of the house which made it nearly impossible to pick up the Charlotte stations which are 100+ miles away.


I recently purchased an Antenna Performance U-92. My install above my garage is not yet finished but preliminary results are promising. I was able to pick up WBTV with low 60's on the 6000. I hope to pick up a couple of the other Charlotte stations when done.


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nick
 
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