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External FM Antenna

Yep, still using the VHF/FM splitter. On the scale of 0-10 for radio reception, the splitter got me from a 2 to a 5/6, and moving the ground took to me a 9.
 
I got the AM/FM VHF Shakespeare band separator, a bit pricey - so I hope it works!
https://www.westmarine.com/buy/shakespeare--4357-s-am-fm-vhf-marine-band-separator--247413

I was about to install it but the PL259 connector will need soldered, it does not come pre-assembled which is a little misleading.
upload_2018-8-28_23-26-36.pngupload_2018-8-28_23-26-50.png

Will be testing it this weekend in AR (Bull Shoals Lake/Mountain Home area) - we have a favorite FM station there I think it's KTLO, but I can hardly get any reception with the OEM FM antenna.

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While you're crawling around in there, I'd recommend moving your radio ground wire to your amp ground if you haven't already. The splitter helped a good bit, but moving the ground totally resolved it for me (I'm wondering if I would have even needed to get the splitter if I tried the ground swap first).
 
While you're crawling around in there, I'd recommend moving your radio ground wire to your amp ground if you haven't already. The splitter helped a good bit, but moving the ground totally resolved it for me (I'm wondering if I would have even needed to get the splitter if I tried the ground swap first).
That's exactly what happened! My HU ground moved eliminated all hum, and this splitter rocks
https://www.westmarine.com/buy/shakespeare--4357-s-am-fm-vhf-marine-band-separator--247413
We arrived at the Bull Shoals Lake today, and I can listen to KTLO 97.9 with better reception than ever - the radio signal on my Connext went up from one bar to 5! Success!

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I finally switched my head unit power and ground to the blue seas block (same as my amp now). Radio reception is back to normal. Still not great reception with a basic two wire spread out inside the hull; but the static is gone.
 
Besides the issue of having the stock antennae buried as you know, the length of the antennae makes a difference in addition to the mounting location.

This is from memory because it’s been 20+ yrs since I worked at a car audio dealer, but a car antennae is ~31” long, which is 1/4 of the radio wavelength. A car antennae is actually “tuned” to the wavelength, so if you added one of those short, rubber antennas to your vehicle, radio reception wouldn't be as good as the stock antennae is.

Again, this is from memory without looking it up for a refresher.
 
Cars get better reception because they have a solid ground plane. I'll bet if you ground the tower to the main battery ground, ground an antenna to the tower and share that same ground for the amps and deck and the signal will improve dramatically.
 
I got the AM/FM VHF Shakespeare band separator, a bit pricey - so I hope it works!
SHAKESPEARE 4357-S AM/FM/VHF Marine Band Separator | West Marine

I was about to install it but the PL259 connector will need soldered, it does not come pre-assembled which is a little misleading.
View attachment 82445View attachment 82446

Will be testing it this weekend in AR (Bull Shoals Lake/Mountain Home area) - we have a favorite FM station there I think it's KTLO, but I can hardly get any reception with the OEM FM antenna.

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Well, in testing the systems before our upcoming Chicago-St. Louis trip I had the VHF stationary in high power (25watts) transmission mode and noticed it jolts the Connext stereo settings (and speakers) when transmitting...

It made me perplexed as I have never experienced that before, but realized this new VHF/FM adapter could be the culprit. I'll test this next time I'm out and report back, but thinking out loud here as it's bothering me.

I hardly ever use the VHF radio when on the lakes, and if I do it is just listening, or communicating between my boat stationary and our backup hand-held unit somewhere else (close-by), that handheld unit is low power so I never switch the stationary VHF in the boat to 25watts and just keep it at 1watt.

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Well, in testing the systems before our upcoming Chicago-St. Louis trip I had the VHF stationary in high power (25watts) transmission mode and noticed it jolts the Connext stereo settings (and speakers) when transmitting...

It made me perplexed as I have never experienced that before, but realized this new VHF/FM adapter could be the culprit. I'll test this next time I'm out and report back, but thinking out loud here as it's bothering me.

I hardly ever use the VHF radio when on the lakes, and if I do it is just listening, or communicating between my boat stationary and our backup hand-held unit somewhere else (close-by), that handheld unit is low power so I never switch the stationary VHF in the boat to 25watts and just keep it at 1watt.

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If the antenna is on the tower I bet if you wrap that vhf antenna wire in foil it will decrease the issue. The interference is coming from the antenna wire being run close to that big factory bundle that has the canbus wires. I wrapped mine with that foil faced sound deadening stuff (forgive me for not remembering the name at the moment). I don't get any interference from the VHF on low or high power.
 
If the antenna is on the tower I bet if you wrap that vhf antenna wire in foil it will decrease the issue. The interference is coming from the antenna wire being run close to that big factory bundle that has the canbus wires. I wrapped mine with that foil faced sound deadening stuff (forgive me for not remembering the name at the moment). I don't get any interference from the VHF on low or high power.
Great! That would be doable with Raammat, or Dynamat, or simple HVAC insulation with alum/foam layers should do.
I plan on testing it by simply disconnecting the Connext FM wire from the adapter/VHF antenna - see if that does the trick.

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