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General Activities => Main Message Board => Topic started by: pbyrne on March 13, 2024, 08:04:23 AM

Title: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: pbyrne on March 13, 2024, 08:04:23 AM
Getting close to launch time here in the freezing north, and need to replace the VHF cable, as it's in poor condition at the masthead; crack and inner shielding is showing.

Recently installed a Vesper Cortex as well, and the antenna is also older so I'd like to replace the cable, and antenna.

Anyone have recommenedations a setup for the Cortex, or in general with respect to VHF cable, and shared VHF/AIS antennas etc?
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: Jim Hardesty on March 13, 2024, 09:38:39 AM
You may want to watch this.

https://www.youtube.com/watch?v=ALuKTUG6bHo&list=PLsT7_jPsZM5pFpq8RX0oxjibknM2Gz361&index=30

Jim
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: waughoo on March 14, 2024, 05:48:38 AM
When I had my mast down, I wanted to make preparations for a future AIS install along with reviving the VHF infrastructure.  I pulled LMR-400 Ultraflex to the top of the mast and installed a Vesper combo AIS/VHF metal whip antena. This antena is tuned to work as best as possible across the VHF band and the AIS band.

At some time later I bought a Vesper Cortex while keeping my VHF.  THE cortex has a splitter built in to allow one less item to be purchased and installed.
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: KWKloeber ‘84 C-30 #3573 on March 14, 2024, 05:36:19 PM
Hey Alex!

I'm wondering on your install why you chose 400 and not LMR240?

-Ken
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: waughoo on March 15, 2024, 05:48:32 PM
Ken,

I was looking at what my transmit power would be at the antenna based on different cable sizes and found there was a rather significant drop in signal wattage with 240 (or anything smaller than lmr400).  I figured since I was installing new, I would go with the biggest I could get.  The cable run to the top of the mast from the radio ends up being 80 ish feet and has a union at the base of the mast and now goes through my AIS first before getting to/from the radio which adds a number of other connectors.  With all this in mind, it seemed to be the best choice to go BIG!!
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: KWKloeber ‘84 C-30 #3573 on March 15, 2024, 11:12:00 PM
Gotcha.  Thanks!
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: pbyrne on March 17, 2024, 01:04:00 PM
Quote from: Jim Hardesty on March 13, 2024, 09:38:39 AMYou may want to watch this.

https://www.youtube.com/watch?v=ALuKTUG6bHo&list=PLsT7_jPsZM5pFpq8RX0oxjibknM2Gz361&index=30

Jim


Thanks for that! Very helpful.

Looks like it's going to be RG213.
https://www.marineoutfitters.ca/index.cfm?addToCart&category=10002|10090|11169&product=79019611&code=VHF%2002

And some of these connectors.
https://www.marineoutfitters.ca/index.cfm?category=10054|10055|10093&product=79009640&code=8051566301874

What's the best way to fish the replacement cable through the mast, and I guess I should replace the interior wiring running to the radio with the same 213 if it isn't already; I doubt it is.

About the antenna, any suggestions for a good AIS antenna?
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: waughoo on March 18, 2024, 04:40:08 PM
I have been rather fond of the vesper AIS/VHF tuned antenna.  I chose that because it is tuned to work as best as possible for the two frequency ranges you'll be sharing it with.  A dedicated AIS only antenna can be tuned for maximum performance on the AIS range, however it would not do well for VHF (and vice versa).
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: pbyrne on March 18, 2024, 05:50:11 PM
Quote from: waughoo on March 18, 2024, 04:40:08 PMI have been rather fond of the vesper AIS/VHF tuned antenna.  I chose that because it is tuned to work as best as possible for the two frequency ranges you'll be sharing it with.  A dedicated AIS only antenna can be tuned for maximum performance on the AIS range, however it would not do well for VHF (and vice versa).

I saw that one.  Is there something special about the Vesper one as opposed to Shakespeare #5215-AIS 36" Classic AIS Squatty Body Antenna https://www.marineoutfitters.ca/index.cfm?category=10054|10055|10644&product=79035986&code=719441100810

I ask, as the local chandlery has the Shakespeare products, but not the Vesper specific.  I'm sure it could be ordere, but does it matter?

Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: robbjd on March 18, 2024, 06:19:55 PM
I went through this same exercise last season when I added a Vesper AIS, and antenna to our boat. AT that time Garmin who now own the Vesper name and product line told me that the Vesper antenna was sold out and was most likely being phased out. I purchased the equivalent Shakespeare 5215 AIS antenna and can attest to great performance with this antenna. A quick online search found the Vesper antenna out of stock at Garmin, and several retailers.

John
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: waughoo on March 18, 2024, 07:14:03 PM
Quote from: pbyrne on March 18, 2024, 05:50:11 PMI ask, as the local chandlery has the Shakespeare products, but not the Vesper specific.  I'm sure it could be ordere, but does it matter?



It likely does not.  I happen to like the vesper products, but any antenna that is made to handle both vhf and ais bands will likely perform fine.  The Shakespeare should do well.
Title: Re: New VHF cable and antenna to be used with Vesper Cortex AIS
Post by: pbyrne on March 19, 2024, 04:42:22 PM
Quote from: waughoo on March 18, 2024, 07:14:03 PM
Quote from: pbyrne on March 18, 2024, 05:50:11 PMI ask, as the local chandlery has the Shakespeare products, but not the Vesper specific.  I'm sure it could be ordere, but does it matter?




It likely does not.  I happen to like the vesper products, but any antenna that is made to handle both vhf and ais bands will likely perform fine.  The Shakespeare should do well.

Yes, I like them too.  The Cortex has been good if a bit complex!  Can't seem to find link for the antenna though.  Maybe Garmin has killed it off...