is this a common thing? I have an indoor Philips MANT510 antenna and am receiving UHF channels just fine, problem is, the antenna isn't picking up any VHF channels. Do i need to keep on experimenting with the rabbit ears and point them in different positions and keep on scanning until it works?

yellow - uhf KCAH-DT 25.1 PBS Watsonville CA 57° 16.7 58
yellow - uhf KCBA 35 FOX SALINAS CA 57° 16.7 35
yellow - vhf KCBA-DT 35.1 FOX SALINAS CA 57° 16.7 13
yellow - vhf KSBW 8 NBC SALINAS CA 57° 16.7 8
yellow - vhf KSBW-DT 8.1 NBC SALINAS CA 57° 16.7 10
yellow - uhf KSMS 67 UNI MONTEREY CA 57° 16.7
yellow - uhf KION 46 CBS MONTEREY CA 122° 13.6 46
yellow - uhf KION-DT 46.1 CBS MONTEREY CA 122° 13.6 32

believe it or not, "rabbit ears" are directional. They are really a dipole antenna and receive best off their side, at right angles to the extended direction. So, if your antenna is pointed properly for the UHF stations, it might not be in the optimum position for the VHF. At 17 miles from the towers and depending on the broadcast power of the stations, you would do much better to put a small urban VHF antenna outside

Check out

http://www.hdtvprimer.com/ANTENNAS/RabbitEars.html

Down near the bottom is an adjustment guide for the lengths.

With some TVs you can just enter the real RF channel number (with the ".1") and it will check for digital broadcasts on that RF channel only, so you won't have to do a full rescan each time. That is, if you enter "10.1" it will try to find a signal on RF channel 10.

I'm a total noob at this VHF stuff so that chart above is really confusing to me, My TV does have a channel finder though but it will only let me put a whole number and not one with a ".1" or such.

Some TV's us a "-1" or "- number". Check your manual.
BTW... what's the make/model# of you TV? Does it have an ATSC tuner?

I'm a total noob at this VHF stuff so that chart above is really confusing to me,
With dipoles set at 45 degrees:
2 3 4 5 6
113” 103” 94” 83” 78”

7 8 9 10 11 12 13
44” 44” 43.5” 43” 42” 41.5” 41”


With dipoles set at 90 degrees:
2 3 4 5 6
109” 99” 91” 80” 74.5”

7 8 9 10 11 12 13
84” 81” 78” 75” 72” 69.5” 67”

The 90 degree chart has to be in error. It shows longer lengths for 7-10 than 6, etc.

http://www.hdtvprimer.com/ANTENNAS/RabbitEars.html

Will HDTV Primer ever fix this or test newer antenna designs?

The 90 degree chart has to be in error. It shows longer lengths for 7-10 than 6, etc.

http://www.hdtvprimer.com/ANTENNAS/RabbitEars.html

Will HDTV Primer ever fix this or test newer antenna designs?

The low band VHF dimensions are for half wave dipoles.

The high band dimensions are for one and a half wave dipoles.

You can use short half wave elements for high band VHF, but the signal level and directionality will be less.

The numbers still seem to be off a bit.

Is there another difference to these calculations vs. the various dipole length calculators found on the web? Most seem to use 2.85E8 for c vs. 3E8, which would yield 98.5" for 2, etc., but even 3E8 would yield 103.6" for 2. The distance between the base of the poles is only about 1".

Thanks,

End effects and element diameter both play into it, for a dipole usually larger diameter elements mean a shorter antenna for a given frequency with every thing else being equil.

Most of the dipole calculators assume a certain frequency to diameter ratio and are usually calculating for a wire antenna.

It looks like the calculations were done with an antenna modeling program which takes more things into account than the simple dipole calculators do.

Most of the dipole calculators assume a certain frequency to diameter ratio and are usually calculating for a wire antenna.

It looks like the calculations were done with an antenna modeling program which takes more things into account than the simple dipole calculators do.

Ok. All the calculators I've seen seem to be geared for amateur use and lower frequencies.

There must be a reason why commercial Low-VHF antennas are typically 110" wide. Is there a convenient chart for UHF dipoles as well?

I know I've seen a different formula for UHF/VHF diploes than the standard HF formula (468/Freq) but I can't remember what it is right now.