or Connect
AVS › AVS Forum › HDTV › HDTV Technical › Increase length of the elements of the CM4221hd
New Posts  All Forums:Forum Nav:

Increase length of the elements of the CM4221hd

post #1 of 12
Thread Starter 
Hey guys.

I bought two new Channel Master 4221hd antennas & I did the balun to boom mod & removed the small plastic element covers but I did not shorted the reflector screen from 24" to 20" as some suggest.

As I'm sure everyone knows the new smaller uhf tv band is channels 14 - 51 so using channel 32 as the center channel would there be any benefit to replacing the 8" V elements with one that are 9.5" long ?

I figure the antenna would achieve more gain over the smaller band verses the 14 - 69 band using the longer elements & may even improve upper vhf gain.

Has anyone tried this & would it be a good idea to try. I have a local metal supplier that I can buy the same gauge
aluminum from so it would just be a matter of swapping the shorter stock V elements wit the longer ones.

Any input on the would be greatly appreciated.



Toronto. Canada.
post #2 of 12
It might help, if you need more gain at the low end of the UHF band, but it might decrease the gain at the CH51 end. You would need to make rapid comparative gain measurements to be sure, as I did on the DHC thread, when I confirmed the benefit of moving the balun out and removing the caps.
The closeup photos and the attachment in that post don't show up unless you log in and hit refresh (F5).

If you increase the length of the elements, you also must increase the vertical distance between the inner and outer bays to match for proper phasing. It also might be necessary to increase the distance between the elements and the reflector for optimum results. Or, to put another way, all dimensions must be increased (including the reflector size) by the same ratio when you move the design center frequency. This is called scaling a design to a different frequency.

I haven't tried it, but was thinking about doing it if I had time.

It would certainly help the Canadian viewers that are trying hard to receive a weak CH23 signal; going longer would increase the gain at the low end at the sacrifice of the high end. DHC member balm, who is trying hard for CH14, would need to increase the dimensions even more, perhaps to 10 or 12 inches.
Edited by rabbit73 - 10/26/13 at 9:44pm
post #3 of 12
CM4221HD with 10-in WHISKERS:

I did a BowLen (Whisker Length) Parameter Sweep on the CM4221HD (Hacked) model to determine the changes to Raw Gain, SWR, F/B & F/R Ratios. As BowLen increases Raw Gain increases with no adverse SWR impact....however, the F/B and especially F/R Ratios are significantly degraded. I provided performance charts for BowLen=10-inches, the longest that I would recommend, but it only improved UHF Raw Gain by 1.0 to 0.6 dB....barely worth the effort. You could also use 9.5-inches with a somewhat smaller Gain improvement, but better F/B & F/R Ratios:

In the 4nec2 model, the Whisker Length is measured from the Tip to the Center of the Feedline wires....in real antennas, the total length of the wire might be a bit longer, depending on the actual mechanical construction.

PS: To increase Gain on CM4221HD, it needs a much bigger REFLECTOR, preferably with the outer portions bent forward, as in mclapp's M4 Super-4-Bay Bowtie with a Double Angle Reflector:

PPS: I'm currently working on finding the "best" size, shape and separation for a Double Angle Reflector using a considerably "different", improved 4-Bay design (at LEAST 48" H x 48" W, before bending outer portions).....stay tuned...
Edited by holl_ands - 10/26/13 at 7:41pm
post #4 of 12
Thread Starter 
Ok, Thanks so much for your input guys I really appreciate it.

The hardest channels for me to receive here in Toronto are 29.1 fox - 23.1 WNLO - 49.1 WNYB - 51.1 ION tv - all from the Buffalo NY area.
I put up an older cm4228 ( the old style ) which has great gain but very directional, and an Antennacraft 5 element vhf hi antenna to pick up CHCH
from Hamilton Ontario. Most other stations are no problem.

I lost 51.1 as soon as I installed the higher gain 4228, and if I aim it pick up 51.1 I then loose other Buffalo stations.

So I bought the two CM4221hd's thinking I might gang them aiming one at the hard the get Buffalo
stations & the other slightly off towards the other Buffalo stations like 2.1 - 4.1 - 7.1 in hopes to pick them all up without using a rotator.
I read though that this most likely won't work well.

It looks like the best option is to maybe do the reflector reduce mod on one of the cm4221's from 24 to 20 inches to widen it's beamwidth and amp it along with
the vhf hi antenna, then feed the tv in my house.

I'm in a bit of a bad spot in Toronto even though my antenna is around 40' in the air it's tough to get Buffalo stations 100 % everyday without dropouts.

Thanks again guys.


post #5 of 12
For CM4221HD (Hacked) I ran an Rmax Parameter Sweep (overall Reflector Rod Length is twice Rmax). Although larger increases in Rmax improved Gain on 470 & 584 MHz, Rmax could only be increased one inch before the Gain on 698 MHz began to decrease. Hence Reflector Rod width modification would need to be limited to only 2-inches...which only improves overall Gain by 0.05 to 0.3 dB (depending on frequency).....which is barely worth the effort:

BTW: To reduce run times, I normally use a beamwidth resolution of 5-deg. At that resolution, I could see NO DIFFERENCE with Rmax reduced to 10-in (20-in wide Reflector Rods).....which is no surprise given the very minor differences in Gain numbers. ALSO, the narrower Reflector Rod width will degrade Hi-VHF performance even further than the so-so performance of the original.

If you want a wider beamwidth antenna (with lower Gain of course), you might want to consider a fairly simple DIY project: an Optimized UHF Hourglass-Loop with Reflector of your choice:
Edited by holl_ands - 10/26/13 at 9:48pm
post #6 of 12
Thread Starter 
I have two original cm4221's with the galvanized screen, two original cm4228's as well as two new cm4221hd's.
I also have a 6' Channel Master parabolic in great condition in my garage I'm not using. These are kind of
useless now as their designed to work from channel 14 - 83 and the pickup elements are short compared
to the new antennas made for 14 - 69.

I guess I will go with the new ones and leave the reflector grid alone.

What are you thoughts on ganging the two new 4221hd's one above the other & offsetting the aim angle around 20 degrees so
as to achieve a wider pickup pattern. I would combine them using a low loss splitter backwards, feeding them into a preamp
that has separate vhf & uhf inputs so I can also feed my vhf high antenna which I would have a few feet below the two uhf's.

Is it worth my trouble to try and achieve a wider pickup pattern this way, I just don't to back to using a rotator.
I have had so much trouble with rotators freezing up in the winter & it just a pain in the butt.

post #7 of 12
Is it worth my trouble to try and achieve a wider pickup pattern this way
It's difficult to predict the results. Usually, it works fine if the two antennas are aimed at the same bearing. The further the offset between the two, the more likely you will experience phase cancellation of the two signals from any particular channel when they arrive at the combiner. I would need to try it to find out.

Forum member IDRick solved a similar problem by curving his reflector backwards to increase the angular coverage; the convex surface faced the elements and the concave surface was at the rear.

In order to eliminate the need for a rotator, how do you feel about mounting two antennas, each aimed at a different direction, with an A/B switch to select whichever is needed?

There are ways to combine the different channels from different directions with multiple antennas using filters, but that is expensive. It becomes a cable company type mini-headend.
Edited by rabbit73 - 10/26/13 at 10:11pm
post #8 of 12
That's exactly what Antennas-Direct has done in their new DB-8e. However, as can be seen in the fol. antenna patterns, the "beam" is very irregular with deep nulls that may or may not be a problem. Per A-D NOTES, the Loss in the RF Combiner is NOT included and hence would reduce the actual Gain by a SIGNIFICANT amount since the antenna patterns do NOT provide Amplitude and Phase matching, as is required for the RF Combiners's Hybrid Transformer to act as a Summer, instead of 3.5-4+ dB Loss or MORE:

Running two separate coax downlead to an A/B Switch (e.g. Radio Shack with Remote Control) would eliminate these indeterminate Loss problems.
Edited by holl_ands - 10/26/13 at 10:08pm
post #9 of 12
Thread Starter 
Thanks for all the thoughts guys.

I been trying to find the ultimate antenna setup for my location for many years.
Back in the analog days it was ghosting that plagued me, now that it's digital that's
no longer a problem but many stations really reduced their output power compared
to the amount they transmitted with their analog signals.
So now it's finding a high gain antenna with a wide enough pick up pattern

I've never tried the Gray Hoverman antennas, maybe they would work better in my area.

I like the two coax idea wit A / B switching, only problem being once I get the signal into the house it will
be split in two via a splitter, one lead to my tv and then off to another two way splitter inside the wall where
it splits in two to feed my Moms tv in her bedroom and the other port runs to the tv downstairs in the
living room.

This is another reason why I don't want to use a rotator, I'm watching tv in my & my mom wants
to watch a channel in a different direction and I'm screwed.

If I had the room to have a few towers I guess I could run two separate antenna systems for the various
sets in the house but that's no really an option.

Back to the drawing board.

post #10 of 12
Split each of the two downleads before any A/B switch, and feed two or more A/B switches, one in each room. Then, each TV can select either antenna. You will need to add a second coax run to each location.

The only problem I see is that each TV must be able to add a channel after scan if it can't pickup all channels on one antenna, which is why I suggested a reflector modification to make the beamwidth of one antenna wider. Otherwise, you would need to rescan when changing to the other antenna. But, maybe you had already solved that problem when you were using your rotator.
Edited by rabbit73 - 10/28/13 at 9:24pm
post #11 of 12
Thread Starter 
Hey: rabbit73.

Ok the reflector bend back mod seems to most practical.

How much would I bend the reflector on my cm4221hd ?

should it be a smooth curved bend or can I mount the antenna in a vice
and just bend each side slightly so the reflector is say 2" - 4" farther
away from the driven elements at the outer edge.


post #12 of 12
Unfortunately, bending back the ends of the DM4221HD's Reflector Rods by 3-inches....or even bending back BOTH the Reflector Rods and the Tines on the Whiskers by 3-inches each doesn't noticeably change the Beamwidth....it's still 60-deg on Ch14, decreasing to 40-deg on Ch51. Here's my Universal 4-Bay Model for the CM4221HD (Hacked) if you want to play with BowSwp and Rswp choices:

I would expect to see that other 4-Bay Antennas, such as original CM4221, will have the same disappointing behavior...
CM UHF (New) CM4221HD 4-Bay W 16 Reflector Rods, 4nec2 by holl_ands, 28Oct2013
CM Reflector Rods (Rswp in inches) and Bowtie Whiskers (BowSwp in inches) Swept Back
CM     to (hopefully) Improve Beamwidth.....NOPE, can't see any improvement....
CM Simple SOURCE Wire. AutoSeg(11) w NO Errors. UHF: Ignore Rwide "TOO FAT" Warnings.
SY Rsrc=0.109   ' SOURCE wire Radius. Adjust for AGT=1.0: UHF=0.109 & HiVHF=0.124
SY Rbow=0.0815   ' Radius (in inches) of BOWTIE elements
SY Rfeed=0.0595   ' FEEDLINE wire Radius
SY Rwide=0.1875   ' Wide FEEDLINE wire Radius (round equivalent to flat line)
SY ZBowII=9.84   ' Distance between the Centers of the two INNER bowties
SY ZBowOI=8.46   ' From Center of INNER bowtie to Center of OUTER bowtie
SY BowLen=7.9   ' Bow Half-Length
SY TineSep=3.94    ' Bow Tine Separation
SY BowSwp=-3.0   ' Bow Forward Sweep distance at tip of the whisker (Back if negative)
SY FedSep=1.18   ' Separation (in inches) between two FEEDLINE wires
SY Hop=0.8   ' Separation between Feedlines at Crossover
SY ZCross=2.00   ' From Center of Feedline Cross-Over to Center of OUTER bowtie
SY Cond=1.67e7   ' Conductivity (Copper=3.0e7, Alum=2.0e7, StainlessSteel=1.67e7)
SY RS=4.25   ' Separation between Reflector Rods and Bowties
SY Rrod=0.0965   ' Radius of Reflector Rods
SY Rspt=0.0965   ' Radius of Reflector Rod Center Vertical Support Bar
SY Rmax=11.8   ' Half-Length of Reflector Rods
SY RG=4.0    ' Gap between Upper Eight and Lower Eight Reflector Rods
SY RD=1.93   ' Distance between Reflector Rods (13.75/7)
SY Rswp=-3.0   ' Amount Reflector Rod ends are Swept Forward or Back (negative)
' Calculated from above INPUT Values:
SY ZBowInr=ZBowII/2     ' Distance from Z=0 to center of INNER bowtie
SY ZBowOut=ZBowII/2+ZBowOI   ' Distance from Z=0 to center of OUTER bowtie
SY Z1=ZBowOut+TineSep/2
SY Z2=ZBowOut
SY Z3=ZBowOut-TineSep/2
SY Z4=ZBowOut-ZCross+1.0
SY Z5=ZBowOut-ZCross
SY Z6=ZBowOut-ZCross-1.0
SY Z7=ZBowInr+TineSep/2
SY Z8=ZBowInr
SY Z9=ZBowInr-TineSep/2
SY YBowN=-FedSep/2
SY YBowP=FedSep/2
SY YMax=FedSep/2+(BowLen^2-(TineSep/2)^2-BowSwp^2)^0.5
'  #segsX1  Y1Z1X2  Y2  Z2radius
GW 1 1RS+2.0YBowN 0RS+2.0  YBowP  0Rsrc
GW 2     1      RS+2.0  YBowP 0RS+1.5    YBowP   0     Rbow
GW 3     1      RS+2.0  YBowN 0RS+1.5    YBowN   0     Rbow
GW  4 9   RS+BowSwpYmax Z7RS  YBowP  Z8Rbow
GW  5 9   RS+BowSwpYmax Z9RS  YBowP  Z8Rbow
GW  6 9RSYBowN Z8   RS+BowSwp -Ymax  Z7Rbow
GW  7 9RSYBowN Z8   RS+BowSwp -Ymax  Z9Rbow
GW  8 9   RS+BowSwpYmax-Z7RS  YBowP -Z8Rbow
GW  9 9   RS+BowSwpYmax-Z9RS  YBowP -Z8Rbow
GW 10 9RSYBowN-Z8   RS+BowSwp -Ymax  -Z7Rbow
GW 11 9RSYBowN-Z8   RS+BowSwp -Ymax   -Z9Rbow
GW 12 9   RS+BowSwpYmax Z1RS  YBowP  Z2Rbow
GW 13 9   RS+BowSwpYmax Z3RS  YBowP  Z2Rbow
GW 14 9RSYBowN Z2   RS+BowSwp -Ymax  Z1Rbow
GW 15 9RSYBowN Z2   RS+BowSwp -Ymax  Z3Rbow
GW 16 9   RS+BowSwpYmax-Z1RS  YBowP -Z2Rbow
GW 17 9   RS+BowSwpYmax-Z3RS  YBowP  -Z2Rbow
GW 18 9RSYBowN-Z2   RS+BowSwp -Ymax  -Z1Rbow
GW 19 9RSYBowN-Z2   RS+BowSwp -Ymax -Z3Rbow
GW 20 1RSYBowP Z2RS  YBowP  Z4Rfeed
GW 21 1RSYBowN Z2RS  YBowN  Z4Rfeed
GW 22 7RSYBowP Z6RS  YBowP  Z8Rfeed
GW 23 7RSYBowN Z6RS  YBowN  Z8Rfeed
GW 24 1RSYBowN Z6RS+Hop/2  0  Z5Rfeed
GW 25 1RSYBowP Z4RS+Hop/2  0  Z5Rfeed
GW 26 1RSYBowP Z6RS-Hop/2  0  Z5Rfeed
GW 27 1RSYBowN Z4RS-Hop/2  0  Z5Rfeed
GW 28 1RSYBowP-Z2RS  YBowP -Z4Rfeed
GW 29 1RSYBowN-Z2RS  YBowN -Z4Rfeed
GW 30 7RSYBowP-Z6RS  YBowP -Z8Rfeed
GW 31 7RSYBowN-Z6RS  YBowN -Z8Rfeed
GW 32 1RSYBowN-Z6RS+Hop/2  0 -Z5Rfeed
GW 33 1RSYBowP-Z4RS+Hop/2  0 -Z5Rfeed
GW 34 1RSYBowP-Z6RS-Hop/2  0 -Z5Rfeed
GW 35 1RSYBowN-Z4RS-Hop/2  0 -Z5Rfeed
GW 36 1RSYBowP Z8RS  YBowP  Z8-1Rwide
GW 37 1RSYBowN Z8RS  YBowN  Z8-1 Rwide
GW 38 1RSYBowP-Z8RS  YBowP -Z8+1Rwide
GW 39 1 RSYBowN-Z8RS  YBowN -Z8+1Rwide
GW 40 3RSYBowP Z8-1RS+1.5  YBowP  2.5Rwide
GW 41 3RSYBowN Z8-1 RS+1.5  YBowN  2.5Rwide
GW 42 3RSYBowP-Z8+1RS+1.5  YBowP -2.5Rwide
GW 43 3 RSYBowN-Z8+1RS+1.5  YBowN -2.5Rwide
GW 44 3RS+1.5  YBowP    0      RS+1.5  YBowP  2.5Rwide
GW 45 3RS+1.5  YBowN    0      RS+1.5  YBowN  2.5Rwide
GW 46 3RS+1.5  YBowP    0      RS+1.5  YBowP -2.5Rwide
GW 47 3 RS+1.5  YBowN    0      RS+1.5  YBowN -2.5Rwide
GW 7013Rswp   -Rmax   RG/2   0   0       RG/2Rrod
GW 71130   0      RG/2   Rswp    Rmax    RG/2Rrod
GW 7213Rswp   -Rmax   RG/2+RD   0   0       RG/2+RDRrod
GW 73130    0      RG/2+RD   Rswp    Rmax    RG/2+RDRrod
GW 7413Rswp   -Rmax   RG/2+2*RD   0   0       RG/2+2*RDRrod
GW 75130    0      RG/2+2*RD   Rswp    Rmax    RG/2+2*RDRrod
GW 7613Rswp   -Rmax   RG/2+3*RD   0   0       RG/2+3*RDRrod
GW 77130    0      RG/2+3*RD   Rswp    Rmax    RG/2+3*RDRrod
GW 7813Rswp   -Rmax   RG/2+4*RD   0   0       RG/2+4*RDRrod
GW 79130    0      RG/2+4*RD   Rswp    Rmax    RG/2+4*RDRrod
GW 8013Rswp   -Rmax   RG/2+5*RD   0   0       RG/2+5*RDRrod
GW 81130    0      RG/2+5*RD   Rswp    Rmax    RG/2+5*RDRrod
GW 8213Rswp   -Rmax   RG/2+6*RD   0   0       RG/2+6*RDRrod
GW 83130    0      RG/2+6*RD   Rswp    Rmax    RG/2+6*RDRrod
GW 8413Rswp   -Rmax   RG/2+7*RD   0   0       RG/2+7*RDRrod
GW 85130    0      RG/2+7*RD   Rswp    Rmax    RG/2+7*RDRrod
GW 8613Rswp   -Rmax  -RG/2   0       0  -RG/2Rrod
GW 87130       0     -RG/2   Rswp    Rmax   -RG/2Rrod
GW 8813Rswp   -Rmax  -RG/2-RD   0       0      -RG/2-RDRrod
GW 89130       0     -RG/2-RD   Rswp    Rmax   -RG/2-RDRrod
GW 9013Rswp   -Rmax  -RG/2-2*RD   0       0      -RG/2-2*RDRrod
GW 91130       0     -RG/2-2*RD   Rswp    Rmax   -RG/2-2*RDRrod
GW 9213Rswp   -Rmax  -RG/2-3*RD   0       0      -RG/2-3*RDRrod
GW 93130       0     -RG/2-3*RD   Rswp    Rmax   -RG/2-3*RDRrod
GW 9413Rswp   -Rmax  -RG/2-4*RD   0       0      -RG/2-4*RDRrod
GW 95130       0     -RG/2-4*RD   Rswp    Rmax   -RG/2-4*RDRrod
GW 9613Rswp   -Rmax  -RG/2-5*RD   0       0      -RG/2-5*RDRrod
GW 97130       0     -RG/2-5*RD   Rswp    Rmax   -RG/2-5*RDRrod
GW 9813Rswp   -Rmax  -RG/2-6*RD   0       0      -RG/2-6*RDRrod
GW 99130       0     -RG/2-6*RD   Rswp    Rmax   -RG/2-6*RDRrod
GW 10013Rswp   -Rmax  -RG/2-7*RD   0       0      -RG/2-7*RDRrod
GW 101130       0     -RG/2-7*RD   Rswp    Rmax   -RG/2-7*RDRrod
GW 102  3       0       0      RG/2   0       0       RG/2+RDRspt
GW 103  3       0       0      RG/2+RD   0       0       RG/2+2*RDRspt
GW 104  3       0       0      RG/2+2*RD   0       0       RG/2+3*RDRspt
GW 105  3       0       0      RG/2+3*RD   0       0       RG/2+4*RDRspt
GW 106  3       0       0      RG/2+4*RD   0       0       RG/2+5*RDRspt
GW 107  3       0       0      RG/2+5*RD   0       0       RG/2+6*RDRspt
GW 108  3       0       0      RG/2+6*RD   0       0       RG/2+7*RDRspt
GW 109  3       0       0     -RG/2   0       0      -RG/2-RDRspt
GW 110  3       0       0     -RG/2-RD   0       0      -RG/2-2*RDRspt
GW 111  3       0       0     -RG/2-2*RD   0       0      -RG/2-3*RDRspt
GW 112  3       0       0     -RG/2-3*RD   0       0      -RG/2-4*RDRspt
GW 113  3       0       0     -RG/2-4*RD   0       0      -RG/2-5*RDRspt
GW 114  3       0       0     -RG/2-5*RD   0       0      -RG/2-6*RDRspt
GW 115  3       0       0     -RG/2-6*RD   0       0      -RG/2-7*RDRspt
GW 11670       0      RG/2   0       0      -RG/2Rspt
GS 0 0 0.0254' Convert above from INCHES to METERS for NEC
GE 0' No Ground Plane
EK 0' Enable Extended Kernel
LD 5 0 0 0 Cond 0' Conductivity
EX 0 1 1 0 1 0' Simulated SOURCE
GN -1' Free Space
' FR Freq Sweep choices in order of increasing calculation time (fm holl_ands):
' FR 0 0 0 0 470 0' Fixed Freq
FR 0 29 0 0 470 12' Freq Sweep 470-806 every 12 MHz - OLD UHF BAND
' FR 0 34 0 0 410 12' Freq Sweep 410-806 every 12 MHz - Even Wider Sweep
' FR 0 39 0 0 470 6' Freq Sweep 470-698 every 6 MHz - PREFERRED FOR UHF
' FR 0 77 0 0 470 3' Freq Sweep 470-698 every 3 MHz
' FR 0 153 0 0 470 1.5' Freq Sweep 470-698 every 1.5 MHz
' FR 0 71 0 0 300 10' Freq Sweep 300-1000 every 10 MHz - WIDEBAND SWEEP
' FR Hi-VHF choices:
' FR 0 15 0 0 174 3' Freq Sweep 174-216 every 3 MHz
' FR 0 29 0 0 174 1.5' Freq Sweep 174-216 every 1.5 MHz - PREFERRED
' FR 0 45 0 0 162 1.5' Freq Sweep 162-228 every 1.5 MHz - Add +/- 12 MHz BW
' FR 0 27 0 0 189 1.5' Freq Sweep 186-228 every 1.5 MHz - SPECIAL
' FR 0 43 0 0 174 1' Freq Sweep 174-216 every 1 MHz - Hi-Rez
' FR 0 23 0 0 198 1' Freq Sweep 198-220 every 1 MHz - Hi-Rez - Ch13 SPECIAL
' FR 0 26 0 0 150 6' Freq Sweep 150-300 every 6 MHz - WIDEBAND SWEEP
' FR Lo-VHF choices:
' FR 0 19 0 0 54 3' Frequency Sweep every 3 MHz for Ch2-6 + FM
' FR 0 35 0 0 54 1' Frequency Sweep every 1 MHz for Ch2-6
' FR 0 36 0 0 75 1' Frequency Sweep every 1 MHz for Ch5 + Ch6 + FM
' FR 0 28 0 0 54 6' Wide Freq Sweep every 6 MHz for Ch2-13
' FR 0 64 0 0 54 12' Super Wide Freq Sweep 54-810 every 12 MHz
' RP choices in order of increasing calculation time:
' RP 0 1 1 1510 90 90 1 1 0 0' 1D Gain toward 0-deg Azimuth - SIDE GAIN
' RP 0 1 1 1510 90 0 1 1 0 0' 1D Gain toward 90-deg Azimuth - FORWARD GAIN
' RP 0 1 1 1510 90 180 1 1 0 0' 1D Gain toward 270-deg Azimuth - REVERSE GAIN
' RP 0 1 37 1510 90 0 1 5 0 0 ' 2D (Left only) Azimuthal Gain Slice
RP 0 1 73 1510 90 0 1 5 0 0' 2D Azimuthal Gain Slice - PREFERRED
' RP 0 73 1 1510 90 0 5 1 0 0 ' 2D Elevation Gain Slice
' RP 0 73 73 1510 90 0 5 5 0 0 ' 3D Lower Hemisphere reveals antenna (Fixed Freq)
' RP 0 285 73 1510 90 0 5 5 0 0' 3D Full Coverage obscures antenna (Fixed Freq)

Edited by holl_ands - 10/28/13 at 11:30pm
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: HDTV Technical
AVS › AVS Forum › HDTV › HDTV Technical › Increase length of the elements of the CM4221hd