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Old Nov 24, 2009, 07:44 PM
A.T. is offline
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Optima, Maxima & Minima - Installation RX, BODA Antenna FAQ, Volts & Range Test.

Previous posts amalgamated for ease of reference:

Flight Preserver and Tips 21Nov10: added picture below.

Optima Servo Bus Voltage Limit - fully charged 2S Lipo Quote:
"Note most manufacturers list the battery voltage using the nominal voltage.
i.e. 4.8v, 6v, 7.4v etc. This does not mean it is the exact voltage limit.
Therefore all these battery types can be used fully charged.
In reality, the Optima RX servo bus (not SPC) can handle far more voltage than the servos.
I do not suggest using both the servo bus and the SPC from the same battery,
it does you no good since the SPC will only draw about 60mah. - Mike."

Notes 1. "a. Reset voltage is 3.5v. Cause of many problems with 2.4 systems
is when people use low power 4 cell packs with high torque servos and they brown out.
Optima cut off voltage is 3.5v, so we suggest a 5 cell+ pack for the servos.
Or... use the SPC to power the RX for additional safety.
A small 2S lipo to SPC would guarantee the RX voltage would never sag. "

Scan mode - difference between a brownout power loss vs. a complete loss .

If the systems browns out (drops below 3.5v for an instant) you will lose the connection but as
soon as the voltage goes back above this you will regain control.
......................This situation is completely avoidable.......................
By monitoring the "Min" battery reading after moving all control surfaces quickly will tell you
how well your battery is performing and if you are at risk.
If you lose power to zero for less than 1 second then the connection will be regained as well,
it is only if you lose power for more than 1 second in Scan mode that you have to recycle power....

"Best to mount 2.4 GHz BODA antenna vertically inside any model for best
overall radiation/reception in relation to signal spread of a 2.4 system.
Just the wire tip is required to be poked out of a carbon fibre fuselage".
Secure antenna with velcro patch (for quick change between modelsl) or zip tie.
Horizontal mounting does not appear to make any difference, as shown in photos & video of Brandon Chitty's large models,

Install twin antenna of Optima 9, Maxima & Minima at 90* if possible, otherwise not as critical as some other brands.
Warning: Hitec RCD Optima 6, 7 & 9ch Receiver Manual,
“RX Antenna should not be placed placed near Engine, Metal Parts or High Current Batteries”.
The other warning notes must also be read.
. Transmitter On First - Off Last to prevent failsafe and other errors.
. Range Check before flying.

Helicopter notes:
Which to use in large model Heli - 7ch single BODA or 9ch Twin BODA?
Antenna maybe sensitive to static discharge - Ground carbon boom where necessary,
especially all C/F model with belt drive and keep antenna well clear of boom.
How To Avoid Static Issues - "Combating Electrostatic"
How To Avoid Static Issues #02
"My Static Fix" - Align T-REX 100-250-450-500-550-600-700
Antenna BODA Installatipn TRex 250 & X-Spec and EVO 50 & Protos - Pictorials.
Tip Wire of the BODA must protrude past the side frames of metal or C/F models,
especially with the Optima 6 & 7, with a single antenna.

1. Photos & instructions for installation in 200mph+ models by jackosmeister

2. Sailplanes & Carbon Fibre Fuselages
Q. Must I cut "big" hole to get the antenna to the outside of the fuselage on my carbon sailplanes?]
A. No, just a small hole for the tag end coming off the booster. Mike --as shown
. Carbon Fiber Fuse... Report - and photos from well known Glider Pilot and Fly RC author Mike Lee
. “On larger or carbon planes,
All you need to expose out of them is the boosted omni-directional antenna (the metal tip with the short wire exiting).
With Balsa or foam planes, you can keep the antenna in the fuselage., Tony Ohm”
. “Actually only the tag end needs to be outside on a carbonfiber fuse.
We've also tried mounting the antenna every which way and it doesn't seem to have any affect on range checks. Mike”.
. Dual Antenna Mounting pictorial.
By Joe Manor of his set up for high speed DSS, see video below.
. Short Antenna for DLG C/F Glider Fuselage - user example with pictures of installation.
NB: Follow this example at own risk and responsibility as not being a Hitec alternative, voids warranty.

Joe Manor accompanied by aviation icon/living legend Burt Rutan
flew a full carbon wing with carbon/Kevlar fuse D80 [Video]
to speeds over 350 Mph with the single antenna Optima 7 mounted vertically inside the fuse (whisker out).
New World 60 DS Record - Joe Manor's Dynamic60 doing 536 kph (333 mph) with Aurora 9 [Video]

Optima RX with BODA Antenna Range Test
“FYI: We did a power down range test today using a motorcycle
because we could not get to the limit in 90 seconds on foot. 1320' (1/4 mile!)
I knew this system was good, but I was blown away! A good range check on 72 was 100'-150'. Mike.“

. Hitec Single Antenna (BODA) is as Good as Dual Antenna system

. Brandon Chitty's 42% Aeroworks Yak - Mike's Video of RX and antenna in two large models.
Single antenna is mounted horizontally with tape to fuselage center cross brace, pictured below..

. Optima 6 shadowed? - Q & A

. Optima Transceivers - Operating Range

. Optima Transceiver (RX) - Servo Move Slower Than Usual - then Rebind.
...(Switched between Normal <> Scan mode with power off before process completed).

. Optima Transceiver (RX) - Servo Wag & Jerky Servo Movements Reasons & Cure - Do Not Fly With This Condition.
(...includes when switching on some ESC) .

. Optima Transceiver (RX) - Servos Stepping - Battery pack (power supply) failing under load.

BODA Antenna Tip
. If tip's plastic sleeve appears separated at base and is a concern, secure with dab "Shoe Goo" or Heatshrink tube. as pictured.
(The base is soft solder and does not abraid the tip wire.)
NB: The length of the tip wire is critical, Do Not Attempt To Fly if the tip wire has been cut short or broken off.

06Feb12: BODA - Is it Necessary excerpt:
" <snip>The main importance in the Sleeve Dipole is in transmitting the telemetry back.
It prevents standing wave reflections in the coax by acting as a balun. (BALanced to UNbalanced)
transformer. In just the receive function the difference would be small.
. 3 Drawings Showing How A Sleeve Works.
Optima & Minima are tuned for optimum range and performance with the BODA in situ.

Transmitter and Receiver Antenna Orientation for best 2.4Ghz Reception

BODA Antenna Holder (10pcs Pack with shaped double sided tape) is Hitec part number #58474
In need, call Hobby Horse 1-800-604-6229 to order.

Replacement 2.4GHz Antenna:
. Receiver - Antenna - Original lengths & DIY Replacements for PPM & 2.4Ghz Hitec, Futaba, GWS, JR & others.
Includes pictures of 2.4Ghz antenna U_FL Connector head & base which have a maximum removal/refit of 5 times.

ex Hitec USA Support Forum Sticky:
Aurora 9, AFHSS Spectra Modules, Optima Transceivers, Minima Receivers
& Telemetry
- FAQ & Undocumented Features
- Mixes, Setups, Tips. {Individual Links often updated}

23 Sep 2013: Added to attachments:
. Instruction manual for Hitec Minima 6L 6S & 6 LITE receivers.
. Instruction manual for Hitec Maxima series of receivers.

Alan Tong
Alan's Hobby, Model & RC FAQ Web Links (quick search = Ctrl+F)

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Last edited by A.T.; Apr 15, 2014 at 05:29 AM. Reason: add Maxima spec sheet
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