Anyone have a VHF/UHF transceiver in their car? If so, any RFI problems?

[hiroshiy]

Update: Diamond rep said I need to talk to a professional installer, which doesn't exist in the central Tokyo area. I have to drive 24 miles to visit the installer.

After some research, Comet (another antenna base manufacturer) has similar products.

トランク・ハッチバック基台 RS-720 | コメット株式会社

www.comet-ant.co.jp

This one's legs look a little wider than Diamond's. I could clamp the rear tailgate lip with an aluminum protection plate.

In the meantime, I screwed Diamond K416 on the tailgate lip without the aluminum plate. I will attach an antenna tomorrow to see how it stands straight up.

 

[reddy]

I'm not sure the aluminum plate is really needed. I thought it might distribute the pressure forces from the mount more evenly along the lip, but you may be able to find other material that is thinner and allow you to get the mount on.

 

[reddy]

Update: Diamond rep said I need to talk to a professional installer, which doesn't exist in the central Tokyo area. I have to drive 24 miles to visit the installer.

After some research, Comet (another antenna base manufacturer) has similar products.

トランク・ハッチバック基台 RS-720 | コメット株式会社

www.comet-ant.co.jp

This one's legs look a little wider than Diamond's. I could clamp the rear tailgate lip with an aluminum protection plate.

In the meantime, I screwed Diamond K416 on the tailgate lip without the aluminum plate. I will attach an antenna tomorrow to see how it stands straight up.

I have used the Comet RS-270 on a previous car, and that worked well. It doesn't have the cable included, and I used it with an N mount triband antenna since it was the only mount that had an N option, since the actual mount and coax is purchased separately. I remember snagging my clothes on it more if I was working around that part of the car, but otherwise I had no issues with it.

 

[hiroshiy]

Another update: today, I got a Comet RS-720 antenna base, so I replaced Diamond K416 with RS-720. Their sizes are similar.

The base's clamp is wider than K416 so that it could clamp both to (1) the lip and (2) the top of the trunk. I thought 2 would be a better location for maximum gain, but again, the weather strip didn't allow the base to clamp fully. Also, the base slightly touches the other side of the body (plastic molding) when the trunk is closed.

The RS-720 comes with two thin little aluminum plates, and I could insert the plates in the clamp. My antenna, Diamond NR950M didn't require a ground.

See attached photos for the temporary installation. I will have a professional installer bury the coax cables in the spine or under the carpet.

 

[hiroshiy]

Another update: today, I got a Comet RS-720 antenna base, so I replaced Diamond K416 with RS-720. Their sizes are similar.

The base's clamp is wider than K416 so that it could clamp both to (1) the lip and (2) the top of the trunk. I thought 2 would be a better location for maximum gain, but again, the weather strip didn't allow the base to clamp fully. Also, the base slightly touches the other side of the body (plastic molding) when the trunk is closed.

The RS-720 comes with two thin little aluminum plates, and I could insert the plates in the clamp. My antenna, Diamond NR950M didn't require a ground.

See attached photos for the temporary installation. I will have a professional installer bury the coax cables in the spine or under the carpet.

After using this setup (Diamond NR950M + Comet RS-720) for two days, I found a critical problem. It's hard to see in the photo, but I realized I couldn't unscrew the antenna from the base when I tried to remove the antenna for a car wash. It felt too tight, but I unscrewed it by loosening the angle bolts and wiggling a little.

The RS-720's hole was just snug with the NR950M, but the hole was too close to the angle adjustments, so the antenna didn't go all the way.

So I removed the RS-720 and re-installed the Diamond K416 base without the aluminum protection plate.

Comet RS-720

Diamond K416

 

[Barry]

Have you ever tried or considered a through the glass mount?

 

[hiroshiy]

Have you ever tried or considered a through the glass mount?

No, because I was a bit worried about the mount's stability at high speeds...

 

[hiroshiy]

OK, professional installation.

 

[hiroshiy]

I have been using the setup for a few weeks, and I wish I could have more antenna gain. So I decided to mount the antenna on the top of the trunk. K416 didn't go all the way there. And another issue: the antenna gets too high, and I would need to remove or fold the antenna every time I park at home AND the office.

So, I tried my luck with K9000+KTH, the motor-drive antenna base. The KTH is the base that attaches to the trunk and secures K9000 on the car.

I will ask the installer to move the coax cable on Friday.

Temporary installation video:

 

[reddy]

I have been using the setup for a few weeks, and I wish I could have more antenna gain. So I decided to mount the antenna on the top of the trunk. K416 didn't go all the way there. And another issue: the antenna gets too high, and I would need to remove or fold the antenna every time I park at home AND the office.

So, I tried my luck with K9000+KTH, the motor-drive antenna base. The KTH is the base that attaches to the trunk and secures K9000 on the car.



I will ask the installer to move the coax cable on Friday.

Temporary installation video:

Nice. I have seen these on luggage racks, but not on a trunk lip mount. I'm a bit concerned that it has a significant amount of projection laterally that may snag on things to the right side of the car, or be attractive to vandals.

Honestly, I know for a fact that I would eventually forget to hit the switch when entering my garage, and seriously torque the mount. I'd be concerned that would leave some damage to the trunk lip where the mount is attached.

 

[hiroshiy]

Nice. I have seen these on luggage racks, but not on a trunk lip mount. I'm a bit concerned that it has a significant amount of projection laterally that may snag on things to the right side of the car, or be attractive to vandals.

Honestly, I know for a fact that I would eventually forget to hit the switch when entering my garage, and seriously torque the mount. I'd be concerned that would leave some damage to the trunk lip where the mount is attached.

Hi, reddy, thanks for the comment!

>vandals

Nothing to worry about! I'm in Japan and I have never heard of it

>garage entry

Yeah, that's the real concern here. Even now with the antenna mounted low, I hit the parking garage roof with the antenna a few times already. I will try my best!

Will post more pics when the pro moves the coax cable on Friday.

 

[Barry]

Hey hiroshiy - I just got back for a 2 1/2 week trip to JA. I only saw 5 Teslas the entire trip and only one HF Yagi

 

[hiroshiy]

Hey hiroshiy - I just got back for a 2 1/2 week trip to JA. I only saw 5 Teslas the entire trip and only one HF Yagi

Hi, Barry,
Teslas are still not very popular here. Half of the passenger vehicles are Kei cars, which are microcars with a max of 4 pax, costing $10,000-$15000 or less. Y is getting traction but is too wide to fit in the mechanical parking in city condominiums. It will take time.

Re; HF - I just started ham radio, so I don't know what kind of people are enjoying which bands, but many people live in condos, and I guess the HF antenna is too long for small balconies In Metro Tokyo, I sometimes find nobody talking in 2m and 70cm bands during the day.

 

[Barry]

Thanks for the info, Hiroshiy. I spent about 5 days in Tokyo, then visited Hakone, Takayama, Kanazawa, Kyoto and Hiroshima. Most travel between cities was via Shinkansen. They work so well and are so clean. Why can't the USA do that?! Beautiful country!

I hear quite a few JA hams in contests (I do 99% CW), but not many otherwise. I know it's diificult to install HF antennas in the cities. I now live in a condo and have the same problem. I used to have a 2m radio in my car, but when I bought my Tesla in 2015, decided to give it up, as the 2m activity has dwindled so much.

 

[hiroshiy]

Today, I asked the professional installer to set up a motor-drive antenna base Diamond K9000 on my 2017 Model X. Originally, I planned to place the base on top of the trunk (the highest position), but the installer pointed out that if I opened the trunk *and* the FWD at the same time, it would hit the base when it closes. I didn't know that the FWD's open and close paths were different!

One potential issue was that the trunk is curvier (=less flat) at the current position than at the top, and there is a tiny gap between the body and the top of the mount. I will need to see how it stands in the long term.