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1945dave
04-09-2012, 02:41 PM
I am not looking for any lectures about inexpensive radios but has anyone used this radio in a boat? I am a two stick kind of guy and the receiver antennae is very short. Will this setup have any range issues with a good electric hull or perhaps the Genesis Cat?

martin
04-09-2012, 06:01 PM
A friend of mine has this same radio in his Genesis & is very pleased with it & hasnt had any problems at all.

JIM MARCUM
04-09-2012, 07:12 PM
You will actually have better range with no interference issues with that "short" 2.4 Gig RX antenna, unlike the FM crystal TX and the crystal RX with a "long" antenna. I have a pile of what were top of the line FM pistol grip and airplane radios - now worthless & collecting dust. They turned all of my 3D airplanes into piles of sticks due to FM interference:nopity:JIM

1945dave
04-09-2012, 07:56 PM
Jim, the short antennae for the Turnigy receiver in question is only 4.5 inches long total. The marine or surface versions of Turnigy radios are longer. There is no way to extend the antennae lead out over the deck so I am concerned. Jim I believe we have met before perhaps at the SGRA Hydro Invitaional years back or the Indy Unlimited. I have been around a long time but am new the electrics and 2.4 ghz.

siberianhusky
04-09-2012, 08:55 PM
Is the antennae attached by a small gold plug or is it soldered on? If it's a plug you can use an aftermarket longer 2.4 antennae as only the very end of the antennae is the "tuned" part, only about a couple inches is actual antennae, the rest is coax feeder to extend that little end part.

1945dave
04-10-2012, 10:48 AM
The antennae is soldered to the receiver board. I have ordered a marine receiver for this radio that has a 26 cm (about 10 inches) antennae lead. I would feel more comfortable with that. There is another boat forum that has been a buzz with this subject and many of the guys say they just lay the antennae flat to the bottom of the radio box and have no problems. Then there are a few that have various equipment for sale saying they could never trust the range of a air receiver used in a surface or boat application. Futaba offers for a price a 15 inch marine antennae option for their receivers.

JIM MARCUM
04-10-2012, 02:28 PM
Dave, that wasn't me at Indy. But it may have been one of my relatives as the family core is in Kansas/Missouri. If 1945 is the year you were born - we do have that in common, as well as a love of RC anything. Hope you didn't take my reply to your thread wrong, I was trying to help, not talk down to you. JIM:tiphat:

PS: If you mount the RX with velcro near the top of the sponson you would have all but about 1/4" of your antenna sticking out. None of my boats have more than 4" showing & I have yet to have any reception issues even at 1/2 mile away.

Prop-a-Gator
11-28-2012, 10:07 PM
Hey Dave, it's been a while. I've been out of boats for a while, but came across this thread Googling for something else. This thread is old, but both you and Jim have been helpful guys so I thought I'd ask if you found the answer you were after.

1945dave
11-29-2012, 10:03 AM
ything
Hey Dave, it's been a while. I've been out of boats for a while, but came across this thread Googling for something else. This thread is old, but both you and Jim have been helpful guys so I thought I'd ask if you found the answer you were after.

Actually, I never had anyone say anything at all about the subject other than what you see here. Just the same, since that time I not only proved to myself total trust in the short antennae that I aquired seven more 6 channel receivers (meant for aircraft) and six 3 channel receivers which do have longer antennae and now use the 3 channel receivers in most of my boats.

Like Jim, I have a ton of now obsolete expensive Futaba PCM FM radios and receivers that are basically paper weights. One of my racing buddies talked me into trading some of my PCM receivers for his obsolete junk but each receiver originally cost more than the complete 2.4 Turnigy setup. Since then however I see these radios being used by many guys on some pretty expensive models. Our local Hobby shop even stocks these Turnigy radios in both the 9 channel aircraft version and the pistol grip surface version. While he doubles the price on the items I get a certain satisfaction knowing I am not alone in going cheap.

By the way, early on I had to prove to my self everything was trust worthy so I experimented with the failsafe programming and gained enough confidence that I trust these systems even more than any of my respected PCM systems.

Perhaps another footnote: I added the Quanum telemetry monitoring system to some of my better models. To have feed back live as to onboard items like battery voltage and temps. This device has a even shorter antennae and gave no thought to trying to get the antennae above the deck line of the boat and I have yet to lose communication with that system either which is also on 2.4 ghz.

Color me very happy with 2.4 and short antennaes.

Dave

Prop-a-Gator
11-29-2012, 12:15 PM
Dave,

Good to hear you proved it for yourself and are satisfied. I was going to chime in to say that you should have no problems passing 2.4Ghz through the fg Genesis hull. The reasons one may still want to stick the tip of the antenna out of the hull would be to avoid radio obstructions from internal components (motor, lipos, etc) as the boat's relative orientation changes and to optimally orient the radiation pattern. These 2.4GHz dipole antennas have a null point along their axis. If you lay the rx antenna horizontally, you will eventually have the null pointing at your tx as you maneuver. This may not matter or be noticeable if your are keeping your boat relatively close as most people do, but if you are pushing your range it can result in glitches or loss of signal.

BTW: only final the ~31mm of your 9x rx antenna is active. The rest is shielded length to help with placement.