New VHF installation - reception problems

[svsonora]

Hi guys,
Well, this isn't for my sailboat but for my runabout.

I installed a VHF radio on my left side console. The antenna cable run is about 6 feet, with the antenna mounted on the portside bimini frame.

Due to space constraints, I had to use a 90 degree adaptor behind the radio unit. I also did not solder the splice at the connection.



I am getting very poor reception. My handheld receives signals much more clearly. If I disconnect the antenna and hold it very close (but not touching), I get very good reception. I tried 2 different adaptors and they both give me the same results.

What should I start looking at to troubleshoot? Thanks in advance.

[continuouswave]

Many radio problems involving self-installed antenna transmission line connectors result from poor installation of the PL-259 connector to the transmission line.

[Jammer]

Originally Posted by svsonora

I also did not solder the splice at the connection.

For antenna connections, if they are the solder type, they must be soldered in order to work reliably. If they are the crimp type, they must be crimped using the proper tool.


It is difficult to solder the connections unless you have practice, or are under the close supervision of someone who is good at it.


Crimp connectors are available:


https://www.theantennafarm.com/catal...ol-182100-2884


As are reasonably priced crimp tools:


https://www.theantennafarm.com/catal...crimpers-1249/




Be sure you get the correct connector and tool for the type of cable you are using. Most marine installations use RG58.

[Pete7]

Once you have the connector sorted out, put the antenna vertical which whilst may not look as cool, will perform better.

Pete

[s/v Jedi]

I recommend you hire a tech (or HAM etc.) to do the antenna cable install. This is not something you can do yourself.

That your reception is worse is good, this is the good shielding of the cabling. You just need someone to make the coax connections.

Then yes, like others wrote, turn the antenna vertical. It’s why they are called “vertical antennas”

[svsonora]

Thank you everyone. I have about 1 foot spare, so i'll try the crimp (just as a learning experience) and if not, hire a tech. I actually didn't know this was a high difficulty install.

BTW I forgot to bring up the antenna in the pic, oops! that is where the antenna is for 'stowed' position when the bimini is down.

[gonesail]

your connections should be waterproofed too. easy to do it with heat shrink tubes. good luck .. you will get it.

[svsonora]

Originally Posted by gonesail

your connections should be waterproofed too. easy to do it with heat shrink tubes. good luck .. you will get it.

Can I goop on some liquid electrical tape? Just curious, I have some big shrink tubing lying around and that'll be much neater.

[stormalong]

From your description I'll bet your shield and core wires are shorted. As others have said attaching PL-259s takes practice. There are some no solder, no crimp connectors out there but they aren't very good on longevity.

[guyrj33]

Originally Posted by svsonora

Thank you everyone. I have about 1 foot spare, so i'll try the crimp (just as a learning experience) and if not, hire a tech. I actually didn't know this was a high difficulty install.

BTW I forgot to bring up the antenna in the pic, oops! that is where the antenna is for 'stowed' position when the bimini is down.

it's not a high difficulty install, but it is a bit fastidious making sure none of the shield wires short with the center conductor and that all of your connections are soldered or crimped correctly.

[thunderhoof]

Verify that all connections are solid (please don't rely on crimping for RF connections) and that there is no short circuit between center conductor and shield (disconnect antenna to do this because many antennas have a DC short from input to shield). Then determine if you have a reliable ground system at the antenna mount. This point should be at a ground plane connected to the water but in installations like yours all parts of the bimini should be electrically tied together and then to the engine ground. Otherwise the entire bimini is an antenna with a completely indeterminate pattern, varying constantly.
What I am saying is that you would be better off with the antenna mounted to a side rail, with that rail grounded.
p.s., don't bring up the handheld VHF as a system that works without a ground system. The antenna is physically close to the transmitter so cable lengths and ground planes are not an issue.

[KP44]

Originally Posted by Jammer

Be sure you get the correct connector and tool for the type of cable you are using. Most marine installations use RG58.

Before I was proficient, I had a local HAM do the soldering for me. Crimps are IMO better than solder if done with the proper crimp tool. And with the right tool, it is easy.

I use RG113 and I think most marine installations use marine grade RG8X or RG113. It is a "one time" expense and well-worth a few extra coins.

[KP44]

HF marine radios and Amateur Radio antennas are different and use a ground plane. High Frequency (HF) radios use the minimum wattage required to communicate - but up to 1500 watts to "bounce" off the ionosphere and communicate world-wide.

Your VHF (very high frequency) radio is 1 watt or 25 watts for line-of-sight communication. Usually 1 watt is sufficient.

[kc6pob]

if you do use a crimp on PL-259, do not use the Shakespeare PL-259-CP-G. The barrel part of the connector that is to be crimped to the coax shield can crush the inner insulating material or potentially short to the inner conductor. And use the proper crimp tool. Pliers to a crappy job and leave sharp edges. i have ruined my share of connectors using the wrong tool.

After attaching the connectorized coax cable to the antenna and radio, do use liquid tape or a self amalgamizing tape (ala Coax Seal) around the exposed metal of the connector. Then wrap with electrical tape or heat shrink tubing if you must. it is the liquid tape or coax seal that will repel water from entering the connector and coax. The heat shrink just keeps things from getting sticky.

73,
kevin
kc6pob

[Brian.D]

@svsonora, Just out of curiosity, what antenna are you using? And how is the coax attached to that antenna?