Wind Speed and Antennas

[BikingBrian]

The price is right ($55) for this 2 meter antenna, but will its 70 mph wind rating cut it in Wrightwood?

http://diamondantenna.net/cp22e.html

[Toolman]

Yes 

[BikingBrian]

Sounds good. I think I'll take down that J Pole and put that 2 meter antenna on the existing mast. I'll lose 440 capability but I don't think that will be a big loss.

[Toolman]

Honestly, I suggest putting up the dual band model. 440 is very useful which is why we put up a 440 repeater as well as 2mtr. and 220. You will end up with a dual band radio eventually any way. 

[BikingBrian]

If I get the dual band radio, then that will stay at home, and then the 2 meter at home will go to Wrightwood. But on the other hand, if I'm going through the trouble to replace the antenna, might as well get a dual band. You're killing me!!!! 

[Toolman]

I'm gonna get hammered on this but here we go. It's only money, you'll make more. 

 The point is, to plan for the future and do it once. It's like buying a tool that will work for now, but could be replaced later and most likely will be. So cry once and do it right and you won't have to upgrade later. One comment I must make after looking at your install of the J-Pole is, replace the side eve mount with a roof top tri-pod. Radio Shack has a fold over tri-pod that will support a 10' 1-1/2 EMT tube that will definitely survive the winds we have. Mine have for 6yrs anyway. I think it runs about 35 bucks and most Radio Shacks carry them. If you decide to go that way, use the sealant that comes with it and Henry's 208 mastic over the mounting plates for weather protection. My mounts don't leak at all with that procedure.

Glen Martin makes the best roof top mounts but you won't need that for a simple VHF-UHF antenna with a 10' mast.

[BikingBrian]

Actually, you do make a good point. Seems like you can buy a mobile rig used and not lose too much when reselling it to upgrade. I can't imagine the same thing working as well for antennas.

I had never looked at the tripod mounts before because (1) they weren't an option with the tile roof down the hill, and (2) didn't want to put holes in the roof. Though now I've taken a closer look at how they attach and it's really no big deal.

Speaking of upgrades, I just won a used Kenwood TM-721A dual band on Ebay, already upgraded with the CTCSS decoder and the TM-731A screen. It doesn't have the "T" molex connector like my TM-241A, it has a 4 pin Cinch Jones connector. Rather than try to find a power cable for that, I'm just inclined to swap out the connector, is there such as thing as a "standard" 12VDC connector?

[Toolman]

Brian, good deal on the Kenwood. You can change out the connector for anything that will handle the current.

The way I mount roof top tri-pods is this.
1) find a desirable location and mount the tri-pod with nothing in it.
2) fasten it to the roof with the hardware included.
3) remove the single leg bolt and tip it over. The other two legs are hinged.
4) take your mast, and insert it into the tri-pod with no antenna mounted on it.
5) use a level to plumb the mast. There are adjusting bolts for doing this. I use 1-1/2 EMT for the mast on these easy jobs and they are strong enough.
6) lean the tri-pod with the mast over again and rest the mast on a saw hoarse (or what ever you have) on the roof.
7) while it's leaned over you a now have easy access for mounting the antenna and securing the coax down the mast.
8 ) raise the tri-pod, mast, antenna assembly up and secure the single bolt that keeps it in place.
9) check it again for plumb, and finish off the zip ties
10) Use Henry's 208 mastic around the mounting pads to weather protect.

I just looked at your out house J-Pole installation and you can lower the mast over and it looks like 10' of mast will hang over the eve. You can easily mount the antenna from a ladder. Or, you could mount everything up and slide it into the tri-pod but 10' of mast and 12' of antenna can be a little hard to handle by yourself so I do it as described above and it's a one man job.

Your done in about 45 minutes. The rest is running the coax to the operating station. When penetrating the side wall or however you penetrate the building, put a rain drip loop in the coax and seal up the penetrating hole with silicone.

[BikingBrian]

Photos of my new setup here: http://www.kj6vzv.com/2012/06/10/updated-cabin-radio-and-antenna-setup/

You're going to hate me for it, but I ended up going cheap and sticking with the 2 meter mono band antenna. I'm not up here as much as you guys, and so I can't justify springing for the dual band antenna. Also, since the eave mount is already a "sunk" cost and I was putting up a cheap antenna, I decided to stick with the eave mount, rather than also investing in a new mast and tripod. Though if a wind takes it all down, then I might just have to fork out the dough for the tripod, and while I'm at it, upgrade to a dual band antenna. 

Thanks anyway for the tripod installation tips. I may need them if my TV antenna experiment (which I posted on another part of the forum) works out, we'll see...

[Toolman]

Brian, the only thing that matters is that it's right for you and your happy with it.

I get asked all the time what kind of motorcycle should I buy. Obviously, I wouldn't suggest a newbie rider to go out and get a Boss Hoss with a chevy V8 in it.
 
 There are no bad motorcycles, they all have two wheels, and a motor. Some are green, some are red. The only thing that matters is that it fits the riders needs and puts a smile on your face at the end of the day. 

[BikingBrian]

Thanks, the above will still be helpful since I just got a tripod to mount my TV antenna. Though I must have gotten a cheaper tripod, since all three legs are not removable. One question, though, were you able to find the roof rafters and get the tripod screws in them? Maybe it's not a big deal for a lightweight vertical radio antenna, but I'll want to be more careful with a heavier TV antenna.

[Toolman]

The chances of all three legs hitting the joist's are pretty slim. If you drill the proper size hole for the lag screw they should tighten down with out stripping out the wood. Measure the root diameter of the lag screw and subtract about .030 and use that drill size. I've never had one strip out. Don't forget to lather the mounts up with Henry's 208

 I wouldn't worry about a light weight TV antenna either. If you are really concerned, what is commonly done with large roof top towers is to sandwich the roof plywood between the top mounting pad of the tower with another plate underneath the plywood in the attic. I think that's rather extreme for your installation though.

 I've got a Radio Shack HD1200 10' long antenna mounted on one of those tri-pods and it's been doing fine.

[BikingBrian]

Good to know, thanks. My cabin is built like a tank, I forget what wood was used for the roof, but I know for sure it's not plywood. My new antenna is only 8' long, so it's got to be lighter than yours. I got a 10' piece of 1-1/4" EMT conduit to use as a mast, as the 1-1/2" might fit but seemed a little snug. The tripod itself adds a bit of height, so I might even cut that conduit in half, so that the install becomes a one man job.

[Toolman]

Try to keep the 10' emt mast if you can, the tripod can handle the load. Set the mast just an inch or so from touching the roof apex, this way you can tilt the tripod over with no interference from the crown of the roof peak. Plumb the mast in the tripod before mounting the antenna.

[BikingBrian]

OK, I've got the tripod thingie finally figured out. There's only one of the three feet you can unbolt, so that it will pivot backwards on the other two. I just need be careful to mount the legs in the right place so that it folds in the direction I need it to. Actually my roof is shallow enough for me to put a sawhorse under a 10' mast in the folded position so I have room to mount the antenna. The only thing I'll have to check is my distance from utility wires. I'll be far enough from the wires in front, but there are some wires running on poles on the side of the property which I need to look out for, though those are only cable and no power I believe. But I think the antenna will still be lower, so that in the worst case scenario of antenna and mast falling over it wouldn't hit any wires.

[BikingBrian]

By the way, I found a photo of the wood under the shingles I'd be mounting the tripod to. See the cut boards next to the dryer vent pipe? (And there's some on the right side of the photo too.) That's the original roof, which the tripod would be mounting to. Looks a lot stronger than plywood. My recollection is that it's about an inch thick.

[Toolman]

Well, what are ya waiting for... grab the drill.... make me proud

[KJ6MTJ]

The price is right ($55) for this 2 meter antenna, but will its 70 mph wind rating cut it in Wrightwood?

http://diamondantenna.net/cp22e.html

I have one of them antennas here - did great awesome for simplex - but one 50 mph wind with a couple of Tumbleweeds ended up putting mine at a 45 degree angel right at where the aluminum rods meet up with the antenna coupling - Took me a while to get it back somewhat straight - i have it now as a back up antenna - I have a diamond x-50 as my primary - I do want to put it up higher up on a some more pole lengths - like the idea of a 5 foot antenna but let the poles take the grunt of the wind - thats my 2 cents worth from Barstow...