VHF-Low Mod
VHF-Low Mod is Likely Not Necessary for our Insane Gain VHF/UHF Models (as only UHF and VHF-Hi are used today for nearly all areas, as such this VHF-Lo mod is not recommended for most areas):
NOTE: Approx 95% of the country will only have UHF & VHF-Hi freqs in their area and should not do this mod (just assemble per their manual's normal assembly instructions)!
For Example: Ch2s - Ch6s are no longer on VHF-low for the vast majority of the US (the channels advertised and shown on the TV set don't represent real frequencies like they did in the analog TV days). For example, your CH 2 on your TV, its real frequency may be Ch25 UHF although it's advertised and displayed as CH 2.
Important Summary Points:
- Ch2s and Ch6s on your TV are usually are "rarely" on VHF-low today, (The Channels on the TV and advertised on the station don't reflect true frequencies any longer like in the analog TV era / days).
- Outside of Philadelphia and only a handful of areas, VHF-low has been completely phased out. Typically only UHF and VHF-hi bands exist today (Chs 2 - 6 real frequencieactually VHF-low still today for the vast majority of the USA). Our Insane Gain VHF/UHF model in its default configuration (instead of this mod) is recommended for nearly all areas outside of Philadelphia, PA. So this VHF-low mod is not recommend for most areas.
- There are a few area exceptions to this VHF-low being phased out rule however, (most namely the Philadelphia, PA area). We recommend trying the default set-up first even if you're in the Philadelphia market though, as in some cases the VHF low stations can be strong enough that they'll come in even with an antenna without VHF-low elements.
- This mod offers only a "modest" VHF-low improvement, but the VHF-low performance specifically, although can be somewhat better then the many compact HDTV antennas on the market today that commonly lack VHF-low elements, it by no means will work as well as an traditional analog style 10ft monster sized VHF/UHF antenna with multiple VHF-low tuned elements. These older style monster sized analog antennas are still king for the VHF-low band at least.
- For the Philadelphia, PA market and the handful of cities that may have a few VHF-low channels still, this mod is something you may experiment with that lowers the antenna's operating frequency for a small VHF-low enhancement, but please note that outside of Philadelphia, few areas will benefit from this mod as VHF-low is entirely extinct in most areas today (typically UHF and VHF-hi are the only TV frequencies still used in nearly all areas of the US today).
- This mod isn't considered a "polished" project by any means, but rather something you can experiment with if you're in the Philadelphia, PA area and feel the default configuration is dropping or missing a VHF-low signal that is on the cuff of coming in. It doesn't require additional antenna parts, but may require some experimentation on your end to find the best result along with some electrical tape, string/rope, and/or zip-ties to secure the newly formed dipole element into the ideal position for example (this will be explained more in detail below).
- Excluding the large (i.e. the 10ft monsters) traditional VHF/UHF antennas like used in the analog TV days, HDTV Antennas today will not likely have VHF-low elements on them at all. They'll almost always have UHF and VHF-hi band elements only (sometimes only UHF elements) for a reason; VHF-low has been phased out for the vast majority of areas in the USA and VHF-low also requires very long elements and lots of antenna space. Due to VHF-low being removed from most areas, a monster sized traditional style outdoor antenna with VHF-low elements may not be at all necessary for many areas.
- The default configuration (not doing this mod) usually produces the best reception result for nearly all areas as all its elements are also focused on the crucial UHF and VHF-hi TV frequencies! We try to reiterate this point with this guide, because we realize it's a common point of confusion with the VHF-hi vs VHF-low frequencies and also the display on TV vs real frequencies used today. The tips below may be helpful in determining this need.
- Yes, VHF is still used to some degree in many areas, but not it's usually VHF-hi, rarely VHF-low. Today, despite CH2s on the TV not changing, " almost all areas only use "Real Frequencies" UHF and VHF-hi frequencies (this applies to the majority of the USA).
- Another common point of confusion is that Chs 2 – 6 on your TV are "not" commonly on VHF-low today in most areas like they were in the analog TV days, (since the digital conversion for most areas their real / physical channels will typically not be the same as the channel used on a TV set).
- If you aren't in the Philadelphia, PA TV market and aren't already aware of there being VHF-low stations in your area, you likely don't need to worry about this mod, as UHF and VHF-hi are typically the only bands used for roughly 95% of the country and oftentimes those areas that have them may be re-broadcasting them on UHF and VHF-hi anyways, as such the default configuration will almost always have best reception result in nearly all cases.
- Default configuration simply means not to construct this mod mentioned on this page, but rather assemble as normal per the manuals that were shipped with the antenna(s).
- We highly recommend trying the antenna in its normal default configuration first using all its VHF-hi elements, as most customers report the mod isn't necessary and the VHF-hi performance (which is much more commonly used) will be better in default configuration.
- Since VHF-low isn't used in most areas outside of Philadelphia, PA (regardless of channel shown on a TV set), even if you're convinced VHF-low is still present in your area, it's highly advisable to go ahead and run a signal report at the site mentioned below, to double-check the "real" frequencies (the real also known as physical channel will be shown within parenthesis) vs only the displayed channels. Additionally you'll need the signal report data to also find their signal strengths, and if there are duplicate UHF and VHF-hi signals of the same programming in your area already (many times there will be re-broadcasts on UHF and VHF-hi as well, but may be under a different callsign).
- Additionally, in the areas that have VHF-low stations,, they are often also being re-broadcsted on UHF or VHF-hi via Translator (repeater) towers or may not be stations of particular interest either (they can oftehn be reserved for low budget stations (namely non-English speaking or religious stations) in many cases for the areas that still have them).
- Sometimes you'll have to dig in the signal report to spot duplicate signals (the callsigns will often be different for the other towers that are re-broadcasting them on UHF or VHF-hi). Even if this signal report doesn't show duplicate UHF and VHF-hi signals for the same VHF-low station, if you google their callsign you may find a Wikipedia page about the station that also lists their "translator stations". Translators are low power repeater towers that will often also re-broadcast the stations on UHF and VHF-hi for various areas. This is another reason we recommend trying the antenna in its default configuration first, as often the mod simply isn't necessary.
- Philadelphia, PA is a strong exception however as it has some network stations on VHF-low only.
- You should run a Signal Report on a recommended site such as Rabbitears (at https://www.rabbitears.info/searchmap.php) to confirm the physical channel (not just display channel) is on CH2 - Ch6 (the true frequency will say "physical" or RF channel (or will be the channel in parenthesis) and to find out how weak the VHF-low channels are (or if there are duplicate VHF-hi or UHF stations for this same programming).
- Note, the antenna may actually pick up strong VHF-low chennels as shown on the rabbitears report highlighted in green, without even this mod, in addition to most if not all the poor (highlighted in red) UHF and VHF-hi signals in just its default configuration. The VHF-low mod however has helped customers with VHF-low channels down to the "fair" (highlighted in yellow) levels, with the antenna mounted outdoors above roof height. It however will not be adequate for those VHF-low stations in a "poor" (highlighted in red) signal strength level and below. You'll unfortunately likely need a very large traditional VHF/UHF antenna (10ft or longer) if the VHF-low stations are important to you and indeed this weak, without duplicate UHF or VHF-hi signals to your home address.
- The VHF-low mod shouldn't reduce the antenna’s UHF range, but the VHF-hi range will be reduced to some degree. Since VHF-hi is more commonly used than VHF-low today, it’s usually not recommended for most areas.
- The mod will likely require some experimentation and in windy areas you may want to devise a method to secure the dipole in position. One method is to angle the dipole elements backward slightly so they can be rested and tied to the corner reflectors beneath them. If this method is chosen, try not to angle them backward excessively as this will drop VHF-low performance and defeating the mod's purpose.
- If you decide to angle the nearly formed dipole elment backwards (but not too aggressively), you'll also want insulate the newly formed dipole elements where they overlap with the reflector elements beneath them (by heatshrink or merely wrapping a few turns of electrical tape around the aluminum tubes) as otherwise they can electrically short out the reception if not insulated where they overlap..
- This mod lowers the operating frequency on our patented VHF/UHF directional antenna version only (not applicable for the UHF only antennas).
- Just to recap, this antenna excels on UHF and VHF-hi in its default configuration, the mod will help improve the VHF-low range a bit by forming a singular off-center fed dipole element for this band. Although this mod may help somewhat on VHF-low, it by no means will have the same VHF-low range as a traditional monster sized VHF/UHF antenna with multiple VHF-low elements on its array.
DETAILED EXPLANATION:
We've cleverly designed our VHF/UHF insane gain directional model so that the VHF-low band can actually be improved by merely swapping a few element positions around to convert the triangular element to what is known as an "Off-Center Dipole" instead. This method will basically form a singular VHF-low element without making the antenna longer. The antenna will still work on UHF and VHF-hi, but the VHF-hi range will be degraded a bit after the mod. This mod will not be needed for most areas as real frequencies in nearly all areas have migrated to UHF or VHF-hi (regardless of channel number used on TV). With digital TV, the channel numbers typically don't depict actual frequencies today. If mounted outside above roof height, it will generally work well for most strong to fair (green to yellow hightlighted stations by running a signal report at the Rabbitears website at https://www.rabbitears.info/searchmap.php,
It may surprise you that channels on your TV mean very little in terms of real frequencies today and only about 5% (estimated) of the country has VHF-low channels still.. Often they'll also have re-broadcasts on UHF and VHF-hi even for the handful of areas with VHF-low stations so you won't have to mess with the VHF-low mod or they'll be limited to non-English or religious stations (generally). Philadelphia, PA is a strong exception however, as its Ch2s and Ch6s are network stations actually still on VHF-low.
As this is a common point of confusion, it should be reminded that this mod isn't necessary for the vast majority of areas as this band has been phased out after the digital TV conversion for nearly the entire country (we'll try to list known few cities that have some VHF-low channels below) and even in those areas they’ll typically have duplicate signals on UHF or VHF-hi or the stations may not be network stations or of particular interest (such as non-English stations, shopping channels, or less known religious stations)
Our VHF/UHF insane gain model uses a specialty patented triangular shape to improve the VHF –hi frequency range and matching over a traditional dipole element in a true Yagi design. The modified triangular loop improves its frequency coverage over using a traditional dipole element for the driven VHF element and is tuned for the crucial UHF and VHF-hi frequencies. However like most HDTV antennas today, in its default configuration it’s tailored for UHF and VHF-hi. We recommend leaving in its default configuration however unless you’ve already confirmed your area indeed has stations whose “real” or “physical” frequencies are still on VHF-low (as in almost every case the stations uses on your TV set no longer depict their actual frequency). This mod is rarely necessary (with Philadelphia being a strong exception).
It should be pointed out that back in the analog TV days, Chs 2 through 6 would be on VHF-low, however today the channels used on your TV rarely depict their real frequencies like they did before the digital conversion. Your Ch4 for example may actually have an UHF frequency today, regardless of the channel used on your TV set. This is why running a signal report before this mod is recommended to retrieve not just the display channel but rather the “real” physical frequency (the Rabbitears link will show the "real" frequency next the display channel in parenthesis ( ). The channel in parenthesis depicts the real channel frequency.
This mod will give a moderate VHF-low improvement for those areas (such as Philadelphia) that still have VHF low signals.
Most moderately sized HDTV antennas today usually won't have VHF-low elements as they generally focus on just the more crucial UHF and VHF-hi frequencies and VHF-low adds considerable size to an antenna. This makes sense for most areas as VHF low has been phased out for the majority of the country, butt there are some exceptions.
In default configuration the antenna focuses on the more commonly used UHF and VHF-hi frequencies today as well, as the VHF low band has been largely phased out for roughly 95% of the country. In some areas, however, such as Philadelphia, PA VHF low does still exist for some of the stations. This mod "helps" fill in this VHF-low gap that can be done anytime of your choosing (no other parts are necessary), however some degree of drop in VHF-hi performance is to be expected (UHF range is usually unchanged).
It should be noted that this mod will in no way exceed the VHF-low capabilities of a much larger, an older style analog antenna that has several VHF low elements, but will typically do a bit better than most modern HDTV antennas of its size and smaller that commonly lack the VHF-low elements. The mod will create an off center fed dipole element for the VHF low band for some moderate abilities on this band, but at the cost of some loss of range on the VHF-hi band (UHF range is usually unchanged after the mod). The antenna will still operate on UHF and VHF-hi (due to third order harmonic), but it should be noted that the VHF hi range may be diminished a bit after the mod. The UHF band will usually have the same range after the mod however.
In its normal UHF and VHF-hi default configuration the antenna will excel on these more popular bands with fair and poor signal pick up abilities, but on VHF-low it's usually limited to strong VHF-low signals only before this mod. The VHF low mod will allow the antenna to retrieve a bit weaker VHF low channels "generally" down to the fair signal strength levels, (the stations highlighted in yellow when inputting your full address / gps coordinates in decimal format at https://www.rabbitears.info/searchmap.php) if installed outside above the height of nearby roofs, but if you have VHF low stations at the red / "poor" signal strengths, an old style 10ft or large antenna with multiple VHF elements specifically, may still be a necessity for your area. This is of course only for those handful of areas that still have such VHF-low stations and they are important to you. Philadelphia, PA is such market that still has VHF low stations, but for most areas VHF low will be non-existent.
*Important Reminder: The mod is only recommended if VHF-low is in your area and of importance, otherwise you'll want to leave it in its default configuration Although ithe mod doesn't reduce UHF range, the VHF hi range will be degraded a degree after the mod.
It's recommended to run a signal report on a site such as https://www.rabbitears.info/searchmap.php.as it's not common to have VHF-low channels outside the Philadelphia market or they may also be broadcasting the same signal on UHF or VHF-hi as well. There are only a handful of cities that have any VHF-low stations and typically the few areas will be the stations will be less popular non-English speaking stations or perhaps a religious station and in many cases they'll have duplicate signals on UHF or VHF-hi for these VHF-low signals. Rabbitears does a good job of keeping their data up to date and will often show the real / physical channels, what's on them and if there is a duplicate signal on UHF or VHF-hi.
*Tip: if you have trouble converting your full address into a decimal coordinate format, if you search your full address on Google and visit the map on Google, you can generally right click with your mouse near you home and it will show and allow you to “copy” your coordinates in decimal format. You can then just paste them directly into the rabbitears site),
Since VHF-low has been largely phased out for the vast majority of the country, current HDTV antennas will rarely have VHF-low elements on them, like traditional TV antennas once had. As these elements take a good bit of space and are almost always reserved on 8ft and larger, traditional VHF/UHF antennas only.
There are only a handful of cities that will have VHF-low (nearly all cities will have UHF and VHF-hi only frequencies today), and in most cases the VHF-low stations will be reserved to non-network stations, such as religious stations and non-English speaking stations or they'll also have a duplicate signal on UHF, however the Philadelphia, PA market is a strong exception. Ch6 and Ch2 stations in Philadelphia are actually still on VHF-low.
Knowing whether you have VHF-low signals in your area can be confusing as Ch2s - Ch6s are still widely used on a TV set, however in most cases the real (also known as "physical") channels are actually a UHF of VHF-hi frequency. So this mod outside of Philadelphia, PA is rarely needed or recommended as it will degrade its VHF-hi range a bit after the modification. Often the VHF-low stations will also re-broadcast their stations on UHF or VHF-hi so if you find one in your area it doesn't necessarily mean you need to do the VHF-low mod. To better figure out whether you should conduct the mod or leave it in its default configuration will requires running a signal report to find your stations "real" or "physical" frequencies and whether they are also broadcasting on UHF or VHF-hi. Outside of Philadelphia, PA it’s quite rare to have network stations on VHF-low today.
HOW WELL DOES THE VHF-LOW MOD WORK?:
Most HDTV antennas today will have very poor VHF-low performance and for a few areas this can be problematic. This antenna is optimized for the crucial UHF and VHF-hi bands in its default configuration as well, as such, usually does very well in retrieving UHF and VHF-hi bands for Strong, Fair, and even Poor signal strengths (as shown in green, yellow, and red highlighted stations on the rebbitears website link mentioned above) for the crucial UHF and VHF-hi bands, if mounted outside above roof height. However for VHF-low, in default configuration, generally only "strong" (green highlighted stations) VHF-low stations will be possible. After the mod, although the VHF-low performance won't be as great as a the former massive sized traditional antennas, customers have reported they're able to pick up VHF-low stations down into the fair signal levels (yellow highlighted stations on Rabbitears) after the mod, but not usually the poor (highlighted in red at rabbitears link mentioned above). The UHF range is usually the same, however it will degrade VHF-hi band performance a bit. The antenna will still have VHF-hi abilities, but its range may not be as great afterwards.
Outside of the very large traditional antennas like used in the old analog days, HDTV antennas today will typically not have any VHF-low elements as only a handful of cities still use these frequencies. Of those handful of areas that do (outside of Philadelphia) often they will also often have duplicate UHF or VHF-high signals or they are often reserved for less watched / low budget stations (i.e. smaller non-English speaking and religious stations), so usually it's not necessary to perform this mod for most.
As a reminder, as we often get customers that assume they have VHF-low channels because they still stations that use Chs 2-6 on their TV, please remember the channels on your TV set rarely depict their real frequencies today, as such in most cases the low channels o))n your TV are no longer on VHF-low. We always recommend trying the antenna in its default confirguration first if possible.
After the mod, the antenna will do a somewhat reasonable job on VHF low, but the reason it's not recommended for most areas is the range on VHF-hi will suffer a bit. So we recommend using the aforementioned Rabbitears link to determine how weak the VHF-low stations really area (and confirm the "real" frequencies are indeed on VHF-low and on it exclusively). If you have VHF-low stations of interest in "red" (poor signal condition) shown on the rabbitears link, you'll likely still need to use a traditional large (10ft or larger likely) like used in the analog TV days, as such cases will require multiple VHF-low elements and this requires a great deal of antenna length.
The antenna is still 60" in length after the mod and does a reasonable job on VHF-low after the mod for its size, but it's highly tailored for the UHF and VHF-hi bands. If mounted outside above roof height, it can usually pick up VHF-low signals that are marked as strong to fair stations highlighted in "GREEN or YELLOW" colors at https://www.rabbitears.info/searchmap.php . It likely won’t be adequate in “poor” VHF-low signal conditions (often highlighted in red) ,however.
If you're in one of the few areas that has stations whose "real" frequencies are still on VHF low and they are this weak (poor signal condition), you'll likely need to stick with a traditional 10ft or larger antenna like used in the old analog TV days.
It should be noted that the antenna will only have one VHF-low element after the mod as such it should not be considered a deep fringe capable antenna on the VHF-low band even after the mod. The UHF and VHF-hi band’s will still function, however the VHF-hi range will be degrade a bit after the VHF-low mod. However customers have reported up to 50 mile VHF-low range after the modification however terrain and strength of stations will always effect maximum range. As such we recommend running a signal report on https://www.rabbitears.info/searchmap.php. If you’re VHF-low station shows a "poor" signal condition (typically highlighted in red on after entering your address decimal coordinates at https://www.rabbitears.info/searchmap.php), you'll likely unfortunately still need to use a very large traditional antenna that has multiple VHF-low elements on its array if such VHF-low station is important to you. These will typically be 10ft or larger VHF/UHF antennas as it requires a great deal of space to have multiple VHF-low elements.
HOW TO PERFORM THE MOD
The mod is very simple, but may sound confusing unless you already have the antenna on hand. It merely involves swapping two elements around. It may require some experimentation on your part.
You’ll assemble the antennas as normal per their included manuals. The only change, is instead of forming the triangular element, you’ll create an “off-center” fed dipole instead. You do this by only using two sides of the triangular element (the longest tube and one of the shorter tubes that would have normally been part of the VHF triangular element). On the VHF side of the black connection box you’ll just install these two tubes only (the longer aluminum tube that would normally be used for the back-side of the triangular element) and one of the short tubes (you’ll have an extra shorter tube left-over that isn’t used for the VHF-low mod).
You may position the two dipole pieces either straight across or angle them backward. If you decide to angle them backward for more support, try not to angle them backward too aggressively as it will lower VHF-low performance by doing so. You'll also want to add heatshrink or simply wrap a few turns of electrical tape around the tubes so that they can't electrically short out with the reflector elements beneath them (this will drop reception if the tubes aren't insulated where they overlap).
If you angle the tubes backward you can hold them in desired position with your secure method of choice (ie zip ties, string / rope and/or electrical tape, not much is needed to secure them in position).
If the mod sounds complicated without the antenna in your hands, it’s will be easier to understand when the antenna is already in your possession. Basically you are swapping just a few element positions and making a dipole element instead of a triangular element on the VHF band.
The relationship of one longer length ( back-side of the former triangular element with one of the shorter sides creates off-center dipole that will resonates down to VHF-low and also has a third order harmonic on the VHF-hi frequencies.
*This mod doesn't effect UHF performance, but will degrade maximum VHF-hi range to some degree.
*This by no means will have equivalent VHF-low performance as a traditional, large sized VHF/UHF antenna. If the Rabbitears site shows the VHF-low station as being "poor" (or highlighted in red) based on your full GPS coordinates, you'll unfortunately most likely need to stick to a traditional (10ft or larger) TV antenna with multiple VHF-low elements to retrieve such VHF low station.
*Just to not waste your time with this mod, please remember to also verify the physical channel (shown in parenthesis next to display channel on the Rabbitears site) is indeed on VHF-low, since in most areas they won't be) and they don't have duplicate signals on UHF or VHF-hi (the signal report may not show all the translator rebroadcast signals, so also try Googling their callsign to retrieve the Wikipedia page. The Wikipedia pages will often also list their translator repeater towers. This is a good sign the station may have duplicate UHF or VHF-hi signals in your area.
Below is a photo in VHF-Lo Mode:
*IMPORTANT: DON’T OVER-TORQUE THE COAX CABLE ON THE CONNECTION BOX’S CONNECTOR (as it may break solder joints) – HAND TIGHTEN ONTO COAX CONNECTOR ONLY!
Mod Instructions (Short Summarized Version):
Step 1: So basically you will dismantle the "Triangular Element" and use two sides of it only (one long tube and one short tube)! Instead of being a large triangle it will create what is known as an "Off-Center" fed dipole.
Step 2: This will not be physically secure / stable,, so we recommend angling it back and nesting it on the corrner reflector behind it (see photo).
Step 3: You will need to electrically "insulate" the crossing tubes with heatshrink or just a few layers of electrical tape so the VHF and UHF bands don't short out.