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Discussion Starter #1
Going to pull the 3023 out of storage and try it at a new location. I have a house in an area where I have some weak signals for channels 26 and 30. NM is around plus 2 to to 3 for each and both are 2 edge. Multipath prone area since it is is an urban area with lots of taller structures within a few blocks to a mile and also some large trees in the vicinity.

Currently using a MXU 47 which can get a whiff of these signals at times but won't lock onto them according to my TV. Need 15 to 15.5 db reading on the signal strength meter to get a lock and watchable picture. Right now they signals are hovering under that around 10 to 12 db.

If I add some hardware cloth to the reflector of the CM 3023 can I improve the signal strength on each of these channels? If so, how big should each piece be for top part and bottom part of the reflector? Will using cable ties to attach to the reflector impact the signal?
 

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You could add hardware cloth to the reflectors but they are already optimized for the channels the antenna receives. From the specs it looks like it covers those channels (real channels 26 & 30).

If you do add the hardware cloth (1/2 x 1/2 inch? easiest to find), I think it should cover the whole reflector. Cable ties won't affect the signal but might break down over time. You can use wire to tie the hardware cloth to the reflectors, it won't be big enough to affect the signal either. What affects the signal is the vertical separation of the horizontal bars.

If you don't try you won't find out if it works. Stranger things have happened.

My $0.02
David
 

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Discussion Starter #4
Holl_ands. The old version or clone of the 4248 minus those diamond shapes pieces. Since the new model is already out of production after only a couple of years I suspect it was not a very good antenna.
 

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UHF CM4248 15El FD-AGI with ALTERNATIVE CORNER REFLECTORS:

I used 4nec2 to compare "stock" CM4248 to several Corner Reflector ALTERNATIVES, finding only very minor improvement...which would be very difficult to notice in actual viewing. If significant improvement is desired, consider extending the Boom by adding more Directors (Twice the Length with Twice the number of Directors should provide about 3 dB improvement)...but Director Sizes and Spacings would need to be determined via on Optimizer Run. An even higher performance alternative would be to use TWO MATCHING Antennas in either a Vertical or Horizontal Stack, which would provide between 2.5 and 10+ dB improvement, depending on Multipath Fade characteristics:
UHF CM4248 15El FD-Yagi + Corner Refl's

UHF CM4248 15-Element Folded Dipole (FD) Yagi with 14 Reflector Rod (RR) Corner Reflector analyzed using 4nec2 from a file posted by user <300ohm>, which was based on Measurements by Ken Nist, posted in an EZNEC file on Comparing some commercially available antennas.
CM3023 is reportedly similar (if not the SAME) as CM4248.

Several Modifications to the Corner Reflector were then analyzed, including adding 12 Reflector Rods half-way between the existing 14 RRs compared to a pair of Screen Reflectors with the same as well as larger widths.

Three versions are shown here:

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a) CM4248 15El FD-Yagi (Original) with 14 Reflector Rods in Corner Reflector:

UHF Raw Gain = 12.2 to 14.5 dBi, F/B & F/R Ratio = 18 dB and SWR (300-ohms) Under 2.6.

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b) CM4248 15El FD-Yagi - Plus 12 RR's Half-Way Between 14 RR's in Corner Reflector:

UHF Raw Gain = 12.5 to 15.0 dBi, F/B & F/R Min = 22 dB and SWR (300-ohms) Under 2.9.

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c) CM4248 15El FD-Yagi - Plus Corner Reflector using a Pair of 23x33-in Screen Reflectors (1x1-in Grid):

UHF Raw Gain = 12.2 to 15.0 dBi, F/B & F/R Ratio Min = 20.0 dB and SWR (300-ohms) Under 2.8.

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All THREE versions are plotted in the Chart, showing only a MINOR (under 0.5 dB) improvement.
The second and third alternatives are essentially the SAME above 518 MHz, but the Reflector Screen version has less Gain on lower Frequencies. Wider variations for each version did NOT provide any improvement. And a variation of the second version with 3 RR's filling in the Apex also did NOT help.

 

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Discussion Starter #6
Thanks Hollands. Ran a test yesterday and determined the MXU 59 and also the 8 bay Super G 1483 are both better than the CM 3023 even on the lower channels. The CM 3023 is a good antenna but could not pick up the weakest signals that the Antennacraft antennas were able to.
 
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