tcp2525

Follow the instructions when cutting and your antenna will work perfectly and yield great performance. I have one and it works great. And if you want to gain an extra 2db, polish the brass rods to a mirror finish with Brasso. This is an old RF engineer trick.

Probably one of the biggest misconception is people assume that just because they go to an "established" brick and mortar car stereo shop they will get a two-way radio installed properly. Do they even have an SWR meter? You'll possibly burn more time and stomach lining dealing with these shops to even get the job remotely done correctly. My suggestion for you is to Google commercial two-way radio installers in your neighborhood. They will probably be more expensive than a car stereo shop, but your chances of getting quality work in a timely fashion is greatly increased. Of course, if you DIY you might find out your install will most likely be better than a stereo shop's.

Sweet!! Looks like you have some unused real estate that can accommodate 5 more.

Agree, but this is why I follow up with a nice thin fender washer on the inside of the roof to distribute the force more evenly when the antenna hits something. I never had any bent sheet metal or antennas ripped out of the roof.

Damn, you made it 6 days without punching a hole in it? That's got to be a new worlds record for having the willpower. You're going to drill, so get it out of your system now.

LOL! Just a little. But it did show an increase in gain. Was it due to the material or the the way the antenna was constructed. It could have been atmospheric conditions changing in the short time it took me to switch antennas. It was a fun experiment that I did when I was bored. Either way, I didn't notice a decrease in performance that would make me to not want to use it for an antenna. Other than cost, if I had to buy it at retail price, it would make for a decent corrosion resistant material that would be perfect for salt water locations. I'm not sure if I would see any performance difference in a double-blind test.

Well, I did the experiment many years back as I acquired a surplus 30' coil of the stuff and did the old 1/4 wave SO-239 test on 70cm. I did notice a substantial increase in signal strength using the old Seat-O-Pants meter. Unfortunately, the old meter, and I mean old, didn't have an RS-485 data acquisition port. That being said, one could argue that I was suffering from the old placebo effect and it was just a figment of my imagination. Either way, it was a fun experiment and what I got for the remainder of the coil on eBay I will stick with copper.

I'm glad you figured it out. The new setup will make you very happy. One piece of advice. Do the work in the most hostile weather possible and make sure you draw some blood. That way you are assured of having a perfect install.

Copper is so old school and outdated, especially on UHF. We now use platinum plated titanium rod. The performance is amazing compared to copper. A 1/4 wave copper ground plane yields unity gain while the same dimension antenna is 1.5db.

You might just want to remove the lightning arrester and toss in a barrel connector and see if it rules out the problem. Much quicker than screwing with it, unless you're doing it this way for a science experiment. Doubtful it's the arrester acting this way as it is either working or not unless water got inside. If you do find it to be the arrester, open it up like you're shucking oysters as we're all curious.

Here's a power divider with N connectors that are sealed by soldering then in place. All possible ways for water to get in are soldered. I can put this on the bottom of the Mariana Trench without wrapping and no water will get in. Let's see you do that with SO-239s. Even Marconi wouldn't use PL-259s

Yep, always good to adhere to proper weatherproofing/waterproofing techniques so you don't have to do the job twice.

And you'll find in Comet's instructions is to seal around that plastic fitting. My 712 is well sealed.

And if you install the heat shrink tubing that has hot melt glue inside it is 100% waterproof. Quality connectors come supplied with a piece of heat shrink. I always keep in stock several hundred feet of heat shrink just in case.

Yep! One can't dispute that. Also, I always follow my connector installs with a high quality heat shrink tubing with hot melt adhesive inside. Water never gets in my coax.