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Discussion Starter #1 (Edited)
I've read all 18 pages of the 4221 Hacks thread and 20 of the 65 pages in the stacking, ganging and combining thread.
Earlier Rabbit recommended a Stellar labs 2476 VHF hi antenna and I have found Youtube reviews showing this as one of the best VHF HI yagis made. The same site that has the 2476 (Newark) has the 4 bay Stellar for $29. I have not yet found the physical dimensions yet nor a review that compares it to other 4 bays but given the performance reports on their other antennas maybe it's a good one.
The install manual is here. Looking at the manual it seems that the feed point is pretty much dead center and the Balun spacing is better than the 4221. The coverage of the center of the whiskers would be 0 if you can rotate the array assembly upon attaching it to the reflector. I am going to do a live chat with Newark tomorrow and see if I can ge dimensions.
 

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That is the 2nd version of that. They cheapened the design, to reduce the size of the box. The original version which is similar to what CM sells, was fine. This isn't.

That black plastic 'vertical 'bar is a/the potential problem. Instead of solid 'rods' they use 22 gauge wires for the wiring harness. I bought one to try and will not buy another!

Compare that in the middle to the one on the left.
Three 4-bay antennas.JPG
 

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Discussion Starter #3
Too late I already pulled the trigger. If I use a larger gauge solid copper wire can I use the same spacing? I am also going to replace the coax jumpers, they were really cheap!
 

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Discussion Starter #4
After looking at how the wires are ran that connect the bays together to the feed point I decided to leave them alone, they are secured in small channels in the molded plastic whisker cap assembly and there's no chance of physical movement causing a fractured connection and at only about 4" long even though they are small there shouldn't be a noticeable gain improvement going bigger I am more concerned about the shrinking size of the reflector assembly and how it might effect performance...
 

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A smaller reflector will usually reduce gain on lower frequencies and lower the F/B ratio. If anything, elements and reflectors should be getting slightly longer due to the shift to using lower frequencies for UHF. Longer reflectors for bowtie antennas tend to provide better performance on VHF-hi. However, proper modelling needs to be done to get an accurate analysis.
 

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Discussion Starter #6
Yeah, That's what I figured too. My initial experiments with varying the distance between the two 4 bays when vertically stacking shows that it produces gain spikes at certain frequencies. In my case I only have 3 UHF channels of concern and they're pretty close together. The real channels for them are 22.24 & 31 so I will try to optimize my spacing for those channels but it's a raw deal that they seem to be making them less powerful.
 
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