Fw: [aprssig] Re: I'm gonna drill....Right tool for the job..

[Brian Webster]

If you are using the 3/8" mount that is not considered an NMO mount. That is
considered a Larsen or PL-259 type connection. The NMO is a specific
reference to the original Motorola design with the 3/4" hole. I would echo
what others have said, use the right NMO hole saw for the job. In all my
vehicles or the last 17 years (about 30 different mounts) I have never had
one leak or rust after using the proper tools and methods for installation.



Thank You,
Brian N2KGC

-----Original Message-----
From: tvsjr at sprynet.com [mailto:tvsjr at sprynet.com]
Sent: Friday, May 05, 2006 5:22 PM
To: TAPR APRS Mailing List; TAPR APRS Mailing List
Subject: Re: Fw: [aprssig] Re: I'm gonna drill....Right tool for the
job..


>The NMO hard mount is designed to be installed entirely from above
>(assuming you use a hole saw or antenna cutter instead of a two-piece
>Greenlee chassis punch).      The mount normally inserts from above,
>coax (without connector) first. It has tabs that hook under the sheet
>metal and a circular flange that centers exactly in the 3/4" hole. . The
>assembly is drawn up tight against the underside of the sheet metal,
>when the locking ring is screwed on from above, and then
>wrench-tightened.

While you have the installation right, you should be careful about sweeping
statements. NMO mounts require either a 3/4" or 3/8" hole, based on the
mount you buy. Quite a few people are going to the 3/8" mount as the hole is
easier to patch if needed, and the theory is that the structural integrity
of the body panel isn't weakened as much. The antenna mounting surface is
identical, however.

Be very careful if using a Greenlee punch... punch a test hole. If you get a
punch for 3/4" conduit (labeled 3/4" externally), it'll make a hole for 3/4"
ID conduit. Needless to say, this is a Bad Thing.

Don't forget a dab of silicon grease in the O-ring channel underneath the
rentention nut.

Terry



_______________________________________________
aprssig mailing list
aprssig at lists.tapr.org
https://lists.tapr.org/cgi-bin/mailman/listinfo/aprssig