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814
Posted on Wednesday, November 14, 2001 - 9:39 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have determined that the CTE Astroplane probably won't fit on my roof. My next choice would be the Skylab 233. I have some questions.
Like the AstroPlane, I'm confused how the mast attaches to the antenna. Copper's site says the antenna is directly mounted to the base. What does that mean? How long are the radials that extend off the antenna?
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Tech181
Posted on Thursday, November 15, 2001 - 12:05 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The T233 sits on TOP of the mast, which needs to be no bigger than 1 3/8" in diameter. The radials are 8 feet in length but because of their angle only stick down 6 or 7 feet below the base of the antenna.

Steve
Tech181
Tech181@copperelectronics.com
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814
Posted on Thursday, November 15, 2001 - 6:57 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I'm really not sure if my mast is bigger than 1 3/8" or not. I am assuming all masts are about the same diameter. So does the coax go up the inside of the mast or something? Is the mounting method used on the T233 as reliable and sturdy as the tradition U-Clamp method? Thanks for answering my questions.

814
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Marconi
Posted on Thursday, November 15, 2001 - 4:17 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Both antennas do have radials that hang down as 181 says. The T233 is probably a little longer than he notes however. My SD'r radials are 107-1/4" which makes for about the same effective height as he notes. A mast (not provided) of appropriate length and diameter is needed for both antennas. This top mast should be at least 8'-10' long. This then hooks to whatever supports the antenna (bottom mast).

On the 233 this mast mounts into the bottom of the hub of the antenna and 181 gives you the maximum size mast that will fit. The coax must run down thru the center of this mast and this is for good reason. The mast is secured to the hub with one or two set screws in the side of the hub. Consider to replace these screws with SS. I replace all hardware with SS before they go up.

The AP radials all mount to a plate about 4"x8" inches. This plate has two u-bolts (not SS) that holds the mast to one side of the plate supporting the antenna. The coax attaches to this plate via an SO-239 assembled built into the plate. With this antenna the coax can run down the outside of the mast but I would run in down thru the top mast section just like the T-233 in order to shield the coax from the antenna radiating field just like the Starduster. It could make a big difference with TVI in your area.

Believe me, both antennas are light and the tubing is delicate. This would seem to make them easy to handle, BUT THEY CAN BE DIFFICULT. Without any head room below, this makes them a little top heavy when mounting to the bottom supporting mast. So BE CAREFUL it does not get away from you and causes you to fall with the antenna or worse get into some power lines nearby.

Once up, they are durable. My SD'r has been up for almost 9 years. The AP will probably give you a better DX signal than the SD'r due to its improved horizontal response. However, you won't loose any contacts due to this fact, I'll bet you.

Be prepared to work the coax fitting in the SD'r. The inside diameter of the SO-239 seems to be a little smaller than US made PL-259 tips. I filed and reduced the tip rather than trying to drill out the SO-239 to get a fit. Use a little grease where the parts go together, it helps after years of exposure. Get them up about 30' feet I think you will be happy.
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814
Posted on Thursday, November 15, 2001 - 7:19 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Marconi: THANK YOU! Thank you for the detailed description. I've decided that the antenna isn't for me. I need the install to be straight forward and easy. The slope of my roof combined with my fear of heights makes me lean back towards the IMAX. I can assemble that on the ground.. And just stick the whole mast in the chimney mount. Getting another mast is also a big turn off. I don't own a pickup or a van. It would be a hassle to get another mast for the T233 or the astroplane. Thanks for providing me with the detailed info. Stopped me from a lot of headache.

814
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The_Axxis
Posted on Wednesday, February 06, 2002 - 4:33 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I've got a Skylab 233 mounted 53 at the base and everybody thinks I'm running a beam.

I get the flatest match I've EVER gotten on any antenna in my life....barely moves off of zero on my Dosy Meters.

I talked to a guy almost 70 miles south of me who was running a "Starduster" clone and he also had a Moonraker 6. He was switching back and forth between the two antennas and it was only about 2 s-units difference. For 2 s-units, I'll take the Skylab! Man, this thing REALLY performs and I don't have constantly turn it to talk to everybody.

Regular radio reports indicate that I'm the loudest station in the area and I never run over 200 watts into it!


THE_AXXIS
Central Ohio
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Scrapiron63
Posted on Thursday, February 07, 2002 - 10:53 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Two s-units doesn't seem like much difference, and its surely lots more difference in cost and trouble between the two antenna systems, you might have a 100 bucks invested, he could easily have 1000 or more. Do you know about the heights of the two antennas, I've seen people compare a beam at 30 ft to a groundplane at 75. Higher is better with any antenna. If his groundplane is anywhere close to the Moonraker, he might be getting reflection off the raker, I've seen that lots of times, just for curiosity, next time you talk to him, ask him to turn the side of the Raker to you, see if it makes any difference in the output of the groundplane.
Something else to think about, it take 4 times the power for each s-unit increase in signal, if the signal meter on your radio is calibrated correct, which few are, most people turn them up, want more movement. What this means, if someone is running 50 watts, putting a "5" on ya, to put a 6, he would need 200 watts, or an antenna with that much gain. To put a '7', he would need 800 watts.
So looking at that, his moonraker is increasing his talkpower 16 times that of the groundplane.
Talking about those signal meters, several times I've had friends buy a new radio, then they tell me, 'I really like my new radio, I 'hear' good on it, but ol so-in-so don't put as much on me as he did with my old radio, can you fix that, ha, I say 'sure, turn their meter up, there happy as hell again. I do like antenna comparisons, thats one of the fun things of radio. scrapiron
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Brad
Posted on Tuesday, May 28, 2002 - 8:53 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i just put together my new t-233 and seem to have ended up with two extra radials. they are both the same and are the smallest diameter rods of the bunch. my question is , do they go some place that the instructions are not clear about or do they go inside some of the other tubing. the instructions are pretty awful as to lack of info so maybe you can help. thanks,brad
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Brad
Posted on Tuesday, May 28, 2002 - 9:56 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

brad again, i figured out what i did wrong,everything is here but how many pieces make up the main mast? it seems like there should be three because there is a hole drilled in the end of the upper one about 4 inches from the top,but the instructions show two. did i install this piece upside down?
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Tech181
Posted on Wednesday, May 29, 2002 - 12:24 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Brad,

The instructions stink...

There are two pieces to the main mast. The bottom part has the hub on it with the SO-239 connector in it. The top part is slightly smalled in diameter and slides down inside. They are both roughly the same length. Fasten them together with the phillips head sheet metal screws provided.

The ground plane radials, or impedence matching radials or whatever you want to call them are two pieces each and are smaller yet in diameter than the main vertical radial.

The three short pieces of aluminum are used to connect to that black plastic ring (which goes around the mast) and the other end of the short aluminum pieces connect to those other black plastic parts. which slide over the previously mentioned ground plane radials.

It's hard to describe this well so if you need further assistance, E-Mail me, and I will send you more instructions.


Steve
Tech181
Tech181@copperelectronics.com
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Brad
Posted on Wednesday, May 29, 2002 - 9:25 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thanks steve, i got the thing together,now i,ll find a mast and put it up this weekend. ill keep the forum posted .brad
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Scott
Posted on Friday, January 30, 2004 - 10:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a problem with my t223.I have a split in the main element,about 2 inches it has been up for 1 year and I only can guess water must have gotten in and split it when it got frozen or I ran too mush watts throught it I did put at 1000 in it.I would like to see if anyone has had the same problem.The swr is still fine but just worried about it before it goes up higher.It is about 25 feet and was going to put it up over 100 feet on my tower.

thanks for you alls time
Scott in Panter country,North Carolina

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