VHF - RAM microphone installation.

[Sailing Steve]

Hi Serge:

Yes I saw that post when I was scouring looking for previous installs - very nice and professional, and meci for sharing in case I hadn't.  Unfortunately I have an older model, and my instrument panel is on the port side of the cockpit.  Maybe I need a new boat for this new RAM install?  

Steve

[Sailing Steve]

Hi Dave;

The ferrite core would be a good start for the RF issues, won't help the speaker volume though.  Then again you never know as with RF strange things happen that don't always make sense.  I used to be in the radio/telecom business and we had a saying for such things, "FM"  F***ing Magic.

As to where to find one, look at any old computer equipment that you may have laying around, typically monitors.  There will be a ferrite core on the cable that can often be re-used, but if you can't find one to re-use, at least you'll know what you're looking for (eBay maybe to buy one, Radio Shack??).

Install it as close to the microphone jack on the RAM cable as possible, and I'd also suggest on the power at the fridge compressor (closes to the RF source - motor brushes likely).  They won't hurt anything, and if doesn't help, move the ferrite core to other power feeds including the VHF radio.  In the case of the power leads, coil them as many times as possible through the ferrite coil to increase it's effectiveness.

RF sneaks in all over and as I said before, sometimes it's won't make sense even when you solve it - FM.

Steve

[Dave Spencer]

Thanks Steve,
I'll hunt around for a ferrite and try some of that FM in the AM.

[Clay Greene]

You can buy ferrites at Radio Shack or you can spend 5x as much and order them from Raymarine. 

[Sailing Steve]

After a few hours of measurements (with some finger crossed guessing) I took the plunge and drilled a hole in the stem of the pedestal and successfully mounted the RAM cable connector inside the pedestal.

The connector is on the forward side of the pedestal, slightly off centre to starboard about the width of the connector as the steering control cables do a slight twist inside the pedestal and I had to split the difference between them for the connector's tail to reside without rubbing against the steering cables/chain.  If a person wanted to have the connector facing aft, I would suggest to reverse the off centre towards the port side.

I was then able to fish the small end (radio connector end) of the RAM cable in from the top of the pedestal (compass and plastic mounting plate removed for access) and out the bottom of the pedestal through a snug clearance factory hole located dead forward at the pedestal base, exiting above the aft water tank.

I then ran the cable aft of the cabin wall to the port side, above fuel tank, fished it through behind the port wall of the head, through the nav table hanging locker into the power panel cavity, and finally to the VHF mounted above the power panel, all out of sight.

All said, I had less than a foot of slack left in the RAM cable.  It may be possible (wasn't prepared to drill a hole to find out my cable was too short - MAY have worked in hindsight) to mount the mic end of the RAM cable in the pedestal ~3" "spacer ring" located between the steering chain sprocket and the compass, if you want a more centered cosmetically pleasing location.

The Standard Horizon RAM cable is 23' vs. Icom's 20', so keep that in mind if you should attempt the same install.

Steve

[skyward]

Hey Steve, thanks for your post...

After a few hours of measurements (with some finger crossed guessing)drilled a hole in the stem of the pedestal and successfully mounted the RAM cable connector inside the pedestal.

Do you have pictures of this location?

[Ron Hill]

Steve : Look in the Mainsheet tech note and you'll find an article on installing a second VHF radio under your engine instrument panel in a MKI C34.  We used the same mast antenna with a slide switch inside by the Nav station.  That way you have the redundancy of 2 radios, but one near the Wheel where you can see the radio face!!   

A thought