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Re: Chimney mount antenna mast



I agree with this.  In fact, depending on the tripod you use, there are a 
couple of ways of strengthening it.  Ideally you would want the screws that 
sink into the roof to go into the roof beams, not just the roofing 
boards.  As a practical matter this is almost always impossible.  As a 
result, many folks have added more wood on the inside of their roofs to 
give the tripod something more to hold on to.  In addition, again depending 
on which tripod you use, it may pay to throw away the small screws they 
give you for attaching it to the roof and get something heftier.   One 
fellow I know did away with the screws and bought some screw stock.  He 
drilled holes through his roof, passed the screw stock through and then was 
able to put on bolts on both the inside and the outside.  He had a South 
River 15 foot tripod with a pair of cushcraft 14 element 2 meter beams on a 
crossbar and it stayed up for years (until he moved).   I've had a South 
River 10 foot tripod on my roof (with larger screws and more wood, not 
screw stock) for about 10 years without incident.  The Glen Martin tripods 
(quadpod?) look like that are better constructed, but they are more 
expensive as well.   On balance, if I had it to do again, I'd probably 
invest in a Glen Martin unit and sleep a little easier at night.




At 09:27 AM 4/17/00 -0400, Dave Tipton wrote:
>I concur.  Go with the tripod.  Yes, you'll lose a little "Strength",
>however, it's much safer over all and with the raw size of some of the
>oscar antennas, you really do want a little "Sway" to absorb some of the
>wind.
>
>Dave, N8KXA
>
>On Mon, 17 Apr 2000 Builderick@aol.com wrote:
>
> > Hey Rich
> > I wouldn't do it...
> > That is a bad choice.
> > THat back and forth motion will disassemble the fire place. Causing 
> expence
> > repairs
> > I'd buy a cheap radio shack tripod. And mount it on the roof. Being 
> sure to
> > reinforce
> > the plywood with 2X4 cut tight between the rafters and using long bolts.
> > Silicon under the mounting brackets before tighting down.
> > A satellite antenna will have a long boom anding to the leverage and 
> twisting
> > motion.
> > A fire place while haveing vertial strength has very small side to side
> > strength
> >
> > Rick
> > ***************sig file below**************************
> >
> > KB0VBZ Rick in Dm79op
> > On aprs and amateur radio satellites uo-22,ko-23,ko-25,t0-31, decode 
> sstv and
> > weather pictures as my hobbie. In construction, rough frame new houses.
> >
> > E-mail can be sent to my mobile phone (110 characters max)
> > using this e-mail address
> > 3035702419@mobile.att.net
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