Is there anywhere where the PROPER hole sizes for different type mount s are given? PL-259 is that 3/4" and NMO is that 1 and 1/8"?
"through the roof" hole sizes ?
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K5MAR
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The hole size for NMO mounts depends on the mount itself. Many, but not all, NMO mounts use a 3/4" hole. I have some older Antenna Specialists NMO mounts that used a 3/8" hole, but required access to both sides for proper installation. I have SO-239 mounts that use everything from 3/8" to 3/4". This varies by model and manufacturer.
I'm not aware of a chart of the proper hole size for the various models of NMO mounts by the different manufacturers, much less a chart for all the various models of different mounts by the various manufacturers. Not impossible to do, but not really useful, as most mounts come with installation instructions.
Mark S.
I'm not aware of a chart of the proper hole size for the various models of NMO mounts by the different manufacturers, much less a chart for all the various models of different mounts by the various manufacturers. Not impossible to do, but not really useful, as most mounts come with installation instructions.
Mark S.
LarrySC
Member
Please dont drill a hole in your roof. Use an L-bracket if you can. Mounting holes are into fender LIP. I use L-brackets with 3/8" hole for the NMO mounts. Look at photos. www.bncantenna.com
jim202
Member
LarrySC said:
I can tell that Larry has never worked in a radio shop. I have seen brand new cars and trucks have the antenna holes drilled in the roof the same day they were purchased. I have done it to my own.
If you want a long lasting antenna installation, do it the right way. When you go to trade in the car or truck, leave the mount on it or go to a body shop and get a hole plug from them. They may not even charge you for it. They buy them by the 100 box fulls.
Most antenna mounts use 3/8 or 3/4. The better radio shops like the NMO style mounst and they use the 3/4 hole. You don't have to have access to the underside of the hole and normally snake the coax cable between the roof and the headliner.
Jim
How exactly is that done? How would you secure the mount? It would seem like it to be nearly impossible to do without dropping the headliner down.jim202 said:
TeRayCodA
Member
Take off the domelight.Using the proper bit,dill the hole,insert the hole cutter,(mine is 3/4"for NMO),take loose the part of the headliner moulding (drivers side),and run a wire-clothes hanger,to meet at the domelight cavity.
Then tape the coax around the wire,pulling it to the opened moulding.Loosen the moulding around the door,pushing coax into the moulding,and under the dash with cable ties.Assemble antenna mount,and domelight,
-You're done!
Then tape the coax around the wire,pulling it to the opened moulding.Loosen the moulding around the door,pushing coax into the moulding,and under the dash with cable ties.Assemble antenna mount,and domelight,
-You're done!
Hey appreciate the comments people,I wanted the sizes for a custom mount , just using the through the roof thing for reference......appreciate it 100%
If you were unable to drill a hole in the roof, what would be the best location and type of mount? I don’t like mag mounts but it seems that placing a 16 inch 800 mag mount antenna on the roof would give you better reception than on the trunk lid. I would really like to use a trunk lid mount, but don’t want to suffer major signal loss. Would this really make that much noticeable difference?????????
LarrySC
Member
Jim202 has the wrong idea. My radio shop has been in one place 35 Years. The reason I dont like roof mounts is because most people at one time or another will forget and whack one of them off in a parking garage. So you try to get a body shop to fix that. I sell them what ever they want and let them install or have someone else to do it. They may work better on the roof and if its a small car or truck, OK. If its a B1G truck/suv then be carefull. Good Luck to all. Larry
yay! That sounds easy. I think I will quit my day job and open a radio shop.TeRayCodA said:
lol.
ummm .. but what if you want to mount somewhere else other than in the center of the roof? Like near the back glass? The headliner would have to be dropped for that, right?
How is the mount/hole protected against moisture?
Well if you wanted near the rear you could either remove the molding and use the same coat hanger method. Or you could still use the domelight area and simply run a sligly longer coax. Just run the coat hanger up and out the hole in the rear. May take a bit of doing but not to hard.
As for the sealing. Well whenever you have to cut a hole in the sheetmetal you will have the poblem of sealing the ceiling (sorry couldnt help that. I know its not a ceiling)
Best may is a good tight gromet to prevent any chafing on the line then I like to use a little silicone to give it a nice tight seal that still gives a bit when jeeded.
As for the sealing. Well whenever you have to cut a hole in the sheetmetal you will have the poblem of sealing the ceiling (sorry couldnt help that. I know its not a ceiling)
Best may is a good tight gromet to prevent any chafing on the line then I like to use a little silicone to give it a nice tight seal that still gives a bit when jeeded.
How would the mount be secured? Isn't there a nut that needs to be tightened on the inside?flyingwolf said:
I have never seen a MNO mount or one being installed. But I would like to try it sometime .. just need to get these questions in my mind answered that I have always had about MNO mounts.
Personally I would drop the rear molding and pull the headliner down a slight bit to get a finger on the nut. Once it starts to tighten up the friction on the roof will hold the nut while you tighten the anteanna. Thats myexperiance anyway.
Thing is I have never had a problem dropping the headliner and going for it. I usually install some other items when I am up there.
Thing is I have never had a problem dropping the headliner and going for it. I usually install some other items when I am up there.
jim202
Member
Roof mounts
I beg to differ with you. Why do you think I chose the NMO style mounts. I like to use the Larson antenna mounts. Th plastic is soft enough that if something is hit with the antenna that could do some damage, the plastic mount generally breaks and falls off. Been using these on all sorts of cars and trucks for about 20 years or so now. Never had to have any body work done as a result. Just provide a new plastic mount and your off and running. The metal roof mount survives with no dammage. Roof remains intact with no damage.
If your having roof damage, then your using the wrong antenna plastic mounts or from a different company that has too hard of a material.
Jim
LarrySC said:
I beg to differ with you. Why do you think I chose the NMO style mounts. I like to use the Larson antenna mounts. Th plastic is soft enough that if something is hit with the antenna that could do some damage, the plastic mount generally breaks and falls off. Been using these on all sorts of cars and trucks for about 20 years or so now. Never had to have any body work done as a result. Just provide a new plastic mount and your off and running. The metal roof mount survives with no dammage. Roof remains intact with no damage.
If your having roof damage, then your using the wrong antenna plastic mounts or from a different company that has too hard of a material.
Jim
K5MAR
Member
crayon said:How would the mount be secured? Isn't there a nut that needs to be tightened on the inside?
I have never seen a MNO mount or one being installed. But I would like to try it sometime .. just need to get these questions in my mind answered that I have always had about MNO mounts.
Your typical NMO mount has a, well, flange (for lack of a better word) attached to the underside of the mount. It is about a half inch or so wide and around one inch long, and has teeth on each end. The coax come out of the bottom of this at a right-angle. You feed the coax through the 3/4 inch hole in the panel (roof, trunk lid, whatever), then see-saw the rest of the mount into the hole. The upper portion of the mount (the nut that has both interior and exterior threads) screws onto the lower portion. The teeth on the flange grip the underside of the panel, keeping it from twisting, as well as providing a ground connection.
Hope that made sense to you. You might try a Google search for possible pictures of the installation, or maybe stop by your local radio shop for a look.
Mark S.
jim202
Member
Re: Roof mounts
Forgot to mention that most pickup trucks and large trucks, you should not have to take the headliner loose. I have always used a light piece of electrical metal snake to get the coax from the roof down to the bottom of the side column. It may take a few tries and some fishing around. Generally you can find a passage on most of the trucks to get the metal snake to pass through. Then just tape the end of the coax to the snake and keep pulling at the bottom till you get the coax.
If your installing more than one antenna. I get the first cable through, then tape the next cable to the first one. When the second one is through, then tape the third one on. Generally you get about 20 feet of coax to play with on the normal mounts. This gives plenty of slack to work the cables through.
One point to consider, I always pull the rear dome light off to see just what kind of space your dealing with. Some of the new pickups don't have the channel across the back like they use to. In this case you have to mount the antennas just a little more forward to get on the other side of the metal that is there.
I always try to get the snake in first before I drill the first hole. That way I know if the run for the cable in the channel where the rear light is will work or not. If not, then I just move the mount forward and go for it.
Working with cars is different. You will probably have to open up the head liner by the mid post behind the drivers seat. Generaly just the above door moulding and seat belt moulding is required. Check the center post before drilling any holes. On the newer cars, you may find a high pressure gas cylinder there to actuate the seat belt system. Be careful not to damage any of the wiring in the post. A wrong move and you could set off the airbag system. If your between the seat and the steering wheel when when you set it off, your probably going to end up some broken ribs if your turned sideways trying to fight with the molding.
I have seen some video of a fire fighter trying to work on the center console to get a victum out of the car. When the air bag fired, it threw him right out of the car and broke his arm.
Jim
Forgot to mention that most pickup trucks and large trucks, you should not have to take the headliner loose. I have always used a light piece of electrical metal snake to get the coax from the roof down to the bottom of the side column. It may take a few tries and some fishing around. Generally you can find a passage on most of the trucks to get the metal snake to pass through. Then just tape the end of the coax to the snake and keep pulling at the bottom till you get the coax.
If your installing more than one antenna. I get the first cable through, then tape the next cable to the first one. When the second one is through, then tape the third one on. Generally you get about 20 feet of coax to play with on the normal mounts. This gives plenty of slack to work the cables through.
One point to consider, I always pull the rear dome light off to see just what kind of space your dealing with. Some of the new pickups don't have the channel across the back like they use to. In this case you have to mount the antennas just a little more forward to get on the other side of the metal that is there.
I always try to get the snake in first before I drill the first hole. That way I know if the run for the cable in the channel where the rear light is will work or not. If not, then I just move the mount forward and go for it.
Working with cars is different. You will probably have to open up the head liner by the mid post behind the drivers seat. Generaly just the above door moulding and seat belt moulding is required. Check the center post before drilling any holes. On the newer cars, you may find a high pressure gas cylinder there to actuate the seat belt system. Be careful not to damage any of the wiring in the post. A wrong move and you could set off the airbag system. If your between the seat and the steering wheel when when you set it off, your probably going to end up some broken ribs if your turned sideways trying to fight with the molding.
I have seen some video of a fire fighter trying to work on the center console to get a victum out of the car. When the air bag fired, it threw him right out of the car and broke his arm.
Jim
TeRayCodA
Member
Also,about the sealing,an NMO mount comes standard with an "O"ring seal.
Since I installed a 1/4 wave VHF MURS antenna in the roof of my truck,compared to the mag-mount,I would'nt have it any other way.
Looks more professional,and no coax running through the doors.
Since I installed a 1/4 wave VHF MURS antenna in the roof of my truck,compared to the mag-mount,I would'nt have it any other way.
Looks more professional,and no coax running through the doors.
Yes sir very much and appreciate all the comments from all on this thread.
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