FUTABA Transmitter 4PM ??????

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Rokieboater

Well-Known Member
Joined
May 12, 2005
Messages
1,593
Took this off of the Futaba USA webpage..........
MAXIMUM OPERATING RANGE:
100m (Except the MINIT system) (Optimum condition) ..

Is this accurate? Seems like a waste of a transmitter for boats. Any advice on this welcome.
 
Robert, I have no idea if this is a BUTT COVER.. or what.. BUT.. range is not an issue.. here is a test i did some time ago..
Futaba users..

From me to you… thank you for choosing Futaba!

I would like to share some range testing I did a year or so ago. I typically don’t share this type of info but to me.. this help qualifies my use and RX choice. Maybe it can help you guys too..

I have a set of written test requirements (Drafted by me) and a fixture made just for testing radio range. The requirements are just a simple set of rules on how the test is performed. Helps make each return test repeatable.

Then I have a test fixture. Its made of foam and has no metal parts on it. It does however hold a full setup… Servos (3), RX, 6.6life Battery, Futaba 10amp Reg, and ON-OFF switch. This fixture also has a horizontal and vertical RX antenna holder. (Sorry I don’t have any pictures of this setup)

The test I conducted was to test the following

On a 3000 foot obstacle free grass runway (no runway lighting or overhead power lines nearby)

FHSS Non-Diversity -vrs- Diversity receivers

TX antenna position options labeled out by Futaba as “options”

Test the orientation of the transmitter (shoulders facing and shoulders 90deg) from the RX ant

What I used for the test:

4PX Transmitter

Futaba R304SB RX (Non-Diversity)

Futaba R324SBS RX (Diversity)

Goals for the test:

Test range of each RX in two (2) RX antenna positions, horizontal and vertical.

Test range of each RX in two (2) of the TX antenna positions, horizontal and vertical.

Qualify the performance of the two different RXs and their antenna positions (we will call them, “Stow, TX ant horizontal” an “Go, TX ant vertical”)

We tested to the following criteria:

Distance to flashing Green/Red on the receivers paring LED

Here is what I found. (Let me summarize)

Using the 304RX

Shortest combo: Transmitter Antenna in the Go Position, shoulders facing the test rig with the RX antenna horizontal and pointing at the user.. 308 feet.

Longest combo: Transmitter Antenna in the Go Position, shoulders facing the test rig with the RX antenna vertical.. 616 feet.

Using the 324RX

Shortest combo: Transmitter Antenna in the Stow Position, shoulders facing the test rig with the RX antenna horizontal and pointing at the user.. 300 feet.

Longest combo: Transmitter Antenna in the Go Position, shoulders facing the test rig with the RX antenna vertical.. 906 feet.

There is a bunch of testing in-between this but this should provide you with a picture.

Summary:

MOST IMPORTANT.. from the testing we concluded and confirmed the transmitter works best with the antenna in the vertical position.

MOST IMPORTANT.. From the testing we concluded and confirmed that the Receiver antenna MUST be in the vertical position during model operation.

All seems normal and legit.. right.. then..

The 324 outperformed the 304 by 290 feet in the optimized test positions.

Not much more to say.. however.. in the past I had done a bunch of “what’s a realistic” distance for an RC boat to be manipulated on the water. From those days past we found that at about 650 feet a 50 inch boat is usable. Meaning I can determine the operation orientation of the boat. Past that point things start to get sketchy… at 700 or so feet.. all bets are off (operator at the shoreline)

Comments welcome..

Grim
 
From experience, I love my 4PM, I’ve ran both long and short courses with both the R203GF receiver and R304SB receiver and had no range issues. That includes not following Grim’s recommendations of antenna out the box and in the upright position

The only problem I’ve had recently has been the R304SB receivers failing on me or shorting out my micro servos. Switching back to the R203GF’s and issues seem to have stopped. Very odd, double checked all my settings in the radio and seems fine (normal mode on the transmitter, correct voltage on the receiver etc.)
 
The R304SB states.. check that last line..

R304SB– T-FHSS Telemetry System 4-Channel Receiver
For Surface Models (01102179-3)
T-FHSS

SIZE:

35.1 mm x 23.2 mm x 8.5 mm

WEIGHT:
6.6 g

OPERATING VOLTAGE:
DC 4.8V-7.4V

USE OF ANALOG SERVOS MAY CAUSE SERVO TROUBLE
 
Hey grim!
Good to know, one of them was analog. The rest have been digital. Think it could be using another brand with that particular receiver? I had to get a very small Savox for 3rd channel/ throttle in my B hydro, burnt both. Then the receiver completely failed eventually mid race.
Dads sport 40 burnt the one analog, then burned two brand new digital micro servos (hitec and savox). Same servos with the R203GF have been bullet proof.
 
All of the Futaba surface radios have that same spec 100m. I was concerned about that too as I was planning on ordering a 4pm. i have it now and we will see.
 
Brando.. when we do see issues with this system.. it's typically when an off brand servo is used.. make sure you have the latest firmware updated in the radio as well..
 
I bought two of the transmitters and now I must purchase 15 receivers. Gonna go with the R324SBS RX

Thanks for all the input. I feel a little better now. About to send them back and buy the 7 but now I can save my money.
 
All of the Futaba surface radios have that same spec 100m. I was concerned about that too as I was planning on ordering a 4pm. i have it now and we will see.

Bob,, the 3PV states 80m.. BUT.. i have yet to hear of any range issues.. (I have not gotten enough requests to range test the 3PV)..
 
Bob,, the 3PV states 80m.. BUT.. i have yet to hear of any range issues.. (I have not gotten enough requests to range test the 3PV)..
Mike, I have been using a 4pls and a 4pl for about 6 years now with no range problems. I just felt it was time for an upgrade. I have a good feeling about the 4pm.
 
I don't know how far the range is on futaba air craft radios, but I flew planes straight up into the clouds where I lost sight of them..

I would close the throttle, and let them just fall until they reappeared... some times they were a dead stick, but I don't know if I lost contact with the plane or not... I know I could fly it far enough away that I couldn't hardly make it out.

The planes were monocoated in a bright orange on top and white on bottom which helped me with orientation when it was very far away..
 
From the 32 to the 14 to the 4PM..they ALL have the same power.. (from my visit to Futaba USA in 2019!

ENJOY with confidence!

Grim
 
IIRC(someone correct me if I'm wrong please), the FCC set a maximum transmitting power of 500miliwatts on all R/C transmitters. Don't remember if it was to prevent radiation caused health issues or to prevent causing problems to nearby electronics. Again, IIRC, that might have excluded the 50MHz systems but those required an FCC license to use. With that said, the only way(that I know of anyway) to get longer range would be to reduce the impedance through the antenna system of the transmitter or increase the sensitivity of the receiver. Doing the later, however, could cause stray signal interference.
 
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