Maximum effort VHF on cruising boat, dinghy, and handhelds

[Jammer]

Originally Posted by KP44

Use as few connections as possible. This cuts down on loss.

This simply isn't true with properly installed connectors. See among other sources this article.



Yesterday the RG393 whip arrived. I connected it along with everything else and measured the loss of the system as a whole -- adding 3 feet of RG393, two N connectors, and an N barrel now necessary to make the test harness fit. The loss changed from 0.58 dB to 0.64 dB at 160 MHz, an 0.06 dB increase.

[KP44]

Originally Posted by Jammer

This simply isn't true with properly installed connectors.

Sounds like you've done a fine job and you're here for accolades.
It is timeless wisdom to have as few connections as possible because even UHF connectors introduce some loss. Saying otherwise will encourage others to install systems with vulnerable links that are not necessary, nor wise.

[S/V Illusion]

Originally Posted by KP44

Sounds like you've done a fine job and you're here for accolades.
It is timeless wisdom to have as few connections as possible because even UHF connectors introduce some loss. Saying otherwise will encourage others to install systems with vulnerable links that are not necessary, nor wise.

Actually, he is correct - properly installed, good quality coax connectors have virtually no insertion loss as has been demonstrated many times.

[Jammer]

Mixed results.


Antenna is attached to the mast. I ended up putting a 3/4" diameter aluminum tube inside the mast and using the U-bolts that came with the antenna brackets. They go around the tube, which transfers the pressure evenly to the side of the mast. Not elegant but workable, see photos. There was some faffing around pulling the u-bolts more or less into position with waxed sail-mending thread and then levering them through the holes in the mast.


My plan for supporting the cable (in a way that didn't allow it to clang against the inside of the mast) was to put cushion clamps every 5' or so, epoxied in place, and then match drill the mast before fishing the cable, then riveting the clamps in place. The epoxy won't hold to the aluminum well enough to allow this to work, I'm 0 for 10 on my second attempt after carefully sanding the clamps with a die grinder right before applying epoxy.


3rd attempt will be rivnuts holding the clamps shut and #10 pan head screws through the mast. Efforts delayed by the arrival of the rigger tomorrow who wants to see the boat with the stick up before making new standing rigging, due to the boat's various shortcomings in this area which are legion.

[jmc42]

Can you explain how you add amateur and other bands to the Standard Horizon HX380? I easily added Marine, FRS, etc. to my Yaesu-65 amateur radio but it is still illegal to transmit unless there is an emergency. If I could find a marine radio licensed radio that could use the amateur stations, that would be great.

[rslifkin]

Originally Posted by Jammer

My plan for supporting the cable (in a way that didn't allow it to clang against the inside of the mast) was to put cushion clamps every 5' or so, epoxied in place, and then match drill the mast before fishing the cable, then riveting the clamps in place. The epoxy won't hold to the aluminum well enough to allow this to work, I'm 0 for 10 on my second attempt after carefully sanding the clamps with a die grinder right before applying epoxy.

Try a dab of 4000UV instead of epoxy. It bonds pretty well to aluminum, so it'll likely be enough to hold the clamps. I'm using it to hold aluminum solar panel brackets to my deck and it's held 40+ kt winds fine even with the stuff under the center of the brackets not fully cured yet (takes a while to cure an inch or more from the edge).

[Jammer]

Originally Posted by jmc42

Can you explain how you add amateur and other bands to the Standard Horizon HX380? I easily added Marine, FRS, etc. to my Yaesu-65 amateur radio but it is still illegal to transmit unless there is an emergency. If I could find a marine radio licensed radio that could use the amateur stations, that would be great.

You use the YCE13 programming software (do a search) and an RT8 programming cable, which connects to the USB port on your computer. The HX380 is type approved for business band so you can lawfully program those frequencies if you are licensed to use them, and you can lawfully program amateur frequencies since type approval isn't required (assuming you are a licensed amateur radio operator).


The most widely available software has a bug so that it won't let you change a channel from low power to high power, so don't do that, and save a copy of the factory channel plan before you change anything.


In practice you need a different antenna to get any sort of reasonable transmit performance on 2 meters.

Some people program the MURS frequencies though technically a separate type approval is required for that, which the HX-380 doesn't have. The HX-380 doesn't support UHF and therefore can't do FRS or GMRS.

[Jammer]

Here is the installation of the rivnuts on the cable. I used 10-24 aluminum rivnuts and 9/16" aluminum cushion clamps, and have 10-24 aluminum machine screws for attachment to the aluminum mast, so there should be no dissimilar metal corrosion.


The holes in the clamps are too small so I drilled them out with a #2 gauge drill bit, which was the recommended size. Overall it's a fiddly process, several minutes per clamp including drilling and installing on the cable, but it is very secure and should be easy to capture with the screws from outside of the mast.