LarryJM
NoVa
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Joined: 11/09/2007
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Gdetrailer wrote:LarryJM writes "To gain 10 to 12DB real signal to noise ratio on 90% of the DTV stations"
If you are looking for an extra 10DB of gain you can buy an INLINE amp that amplifies from 54mhz to 800mhz. The inline costs about $20 and can be bought at a local Radio Shack. The inline can pass 12V through by removing the one end which is designed to block the voltage. The inline will use the 12V from the existing setup and pass it onto the Winegard amp head. The best place to add in the amp is right at the antenna. Disconnect the cable and put INLINE.
Just plain to simple...
No need to buy a "special" HD UHF antenna, period. Doing so is buying into the marketing hype.
In line amplifiers do nothing to get a better signal to noise ratio for the digital conversion process to work, they amplify not only the signal, but the noise and if the SNR for digital processing falls short then you get the broken picture or no picture at all.
Larry
2001 standard box 7.3L E-350 PSD Van with 4.10 rear and 2007 Holiday Rambler Aluma-Lite 8306S Been RV'ing since 1974. TRAILER MODS
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LarryJM
NoVa
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wa8yxm wrote:Many people are putting some cheap UHF ONLY antennas up there that are being touted for "Digital" or "HDTV"
problem is... not all Digital will be UHF and the same antenna has other features too (did you know you can use it for FM radio?)
I'd not bother with replacement till it's needed
What I linked to is not a "cheap" UHF antenna, but one of the best around and it's not about being digital, but what TV freq band it's designed for. The Batwing design is just a dipole antenna and not really that efficient. All your home antennas are actually two antennas one for VHF and one for UHF.
As far as FM even in my current trailer I have a separate antenna for FM and I think you will find that most RVs don't use the RVs antenna for FM.
Larry
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SCVJeff
Santa Clarita, CA.
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Joined: 07/28/2006
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I saw a bowtie arrangement in Quartzsite last year that clamps onto the batwing mast and collapses with it just fine (a little shorter than the one above). There's no reason you cannot mix the two antennas with a band-splitter up on the mast as long as the VHF tap is DC passive to feed the pre-amp in the wing.
I have been playing with the Batwing up against a Winegard Square Shooter antenna that was developed awhile back with super high F/B radio to try and keep the UHF multi-path under control, and the batwing performs just as good, it just doesn't have the same rejection off the rear of the antenna. I too think I would not do anything until you know what kind of trouble you're going to be in.
Jeff - WA6EQU
'06 Itasca Meridian 34H, CAT C7/350
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wa8yxm
Wherever I happen to park
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Joined: 07/04/2006
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LarryJM wrote:Fulltimer50 wrote:The current antenna that most everyone has works just fine for HDTV/DTV.
Fine is a matter of preception and for VHF I have found that to be true, but UHF is a different story and as I said more than 90% of the DTV freqs will be in the UHF band when the change over happens and is what I was addressing.
Larry
Well.. You can test it now you know.. The batwing I have seems to do UHF just fine, both analog and digital.
Nothin adds excitment like something that is none of your business
John is Near Kenwood TS-2000 housed in a 2005 Damon Intruder 377
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tallbrad
Tx
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Joined: 03/09/2007
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As others have said, your current batwing will work just fine, and the addition of an inline amplifier will make it even better. Have you considered the narrow 20 degree bandwidth of the antenna in your link ? That means you will need to be pointing right at the transmitting antenna to get anything. Could spend a lot of time searching for the right direction, and if the other channels you might want are more than 20 degrees away in azimuth you will not get them with out reajustments.
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mikestock
Vestavia Hills, AL, USA
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Joined: 12/01/2002
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You come into my area with a UHF only antenna you may not be able to pick up the local ABC affiliate after next February. Although they were originally on the analog UHF band they are transmitting digital HD on the VHF band.
Other digital broadcasts may move to the VHF band in the future according to a report I read. I wouldn't depend on the UHF antenna being the answer to digital.
2005 F250 Crew Cab LWB Power Stroke, 2007 Montana 3500RL Fifth Wheel,Honda EU3000IS, Honda EU2000i, Porta Bote with 6HP Nissan and sail kit, S&W security system
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SCVJeff
Santa Clarita, CA.
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HERE is the nationwide Analog, plus Pre- & Post- DTV assignments. While there may be one or two that won't be where shown here, this is what will be.
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JimK
Ohio's North Coast
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Joined: 09/06/2001
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LarryJM wrote:
. . . clip . . .
The Batwing design is just a dipole antenna and not really that efficient. All your home antennas are actually two antennas one for VHF and one for UHF.
. . . clip . . .
Larry
Try taking one of those batwings apart - they are not just a simple dipole. They include a UHF element but, due to the shorter wavelength requirements of UHF, the UHF element is entirely inside the plastic housing. That also accounts for the directionality of the batwing. A simple dipole would be bi-directional but, with the VHF element acting as a reflector for the UHF element, reception is better off the front of the batwing, especially for UHF stations.
Jim and Cathy
GMC 2500HD, Ext. cab. 6.0L. V8 4WD
2005 Trail Bay 27DS
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wa8yxm
Wherever I happen to park
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LarryJM wrote:
What I linked to is not a "cheap" UHF antenna, but one of the best around and it's not about being digital, but what TV freq band it's designed for. The Batwing design is just a dipole antenna and not really that efficient. All your home antennas are actually two antennas one for VHF and one for UHF.
I agree Larry, what you linked to appears to be a decent UHF antenna, I have, however, seen a 20 dollar set top bow tie 300 ohm antenna with matching transformer sold for 100 at rallies and that's why the warning.
I also design and build antennas for my own use., been doing it for many years. (FOR MY OWN USE) on all sorts of bands. (Comes with the UID don't you know)
Still, though you are correct I still don't see the need to replace the batwing this season.. Now in time (perhaps 5-10 years) I may need to replace it, and it is for sure I will consider the UHF only designs when I do, but till it goes south I don't think it's worth the time let alone the cost.
As to the person who spoke of the in-line pre-amps from R.S. (and other sources) A pre-amp like that is good for overcoming line loss in a long transmission line.. In fact when I set up the television system at my parent's old house (100' tower, Channel Master's biggest tower topper, mast head pre-amp) 8 point distribution system down below) we used one.
however pre-amps amplify everything, both the signal you are looking for and noise that may be around it, plus they generate noise themselves (even the low noise ones) and this can offset any improvement.
The antenna that Larry linked to can "Tune out" much of the noise since it is directional and much of the noise is coming off the sides or back In fact, This is one major benefit of the bow tie and reflector design, front to back rejection is very high in this design
(Front to back rejection on teh batwing design is zero
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