FUTABA 6EX DUAL BAND 72 Mhz / FrSky 2.4 MOD - RC Groups
Thread Tools
May 24, 2012, 11:23 PM
Jsutherland8's Avatar


Here is a great way to upgrade a older 72 Mhz Transmitter to 2.4 Ghz, and still use it with 72 Mhz RX's.
The Futaba 6-EX PCM is a, rock solid, radio that will do PPM output too, so it is easy to put in a FrSky V8HT and get a new life with 2.4 Ghz ACCST TX MOD.

I have done several JR's and TH 9X. 2.4 Ghz MOD's, and this one was easy, nice and clean looking, with little change to the outer case of the TX.

After the removal of the battery, crystal, antenna, and case back, pull up the RF PCB and flip it down to the right bottom of the TX. Remove a bit of the plastic beside the trainer switch so the Mode switch will fit in with the spline or flat washer flush to the edge of the case.
Here are the pictures in a step by step order. The big trick is to lay it out and measure twice and drill once. I use a 6" digital caliper to measure parts and find and scratch center lines for holes. I changed the small 3mm LED to a 5mm bigger bi-colour to make it easy to see. The DPDT switch allows for dual band operation, but can be left out if you only want a 2.4 Ghz system. The 2.4 Ghz antenna could be mounted in the hole where the 72 Mhz flag pole was. I also did a set of range tests with, and without the 72 Mhz antenna inplace with the 2.4 Ghz antenna in 4 positions, and saw little or no difference in TX distance. The 72 Mhz antenna can be taken off when 2.4 Ghz TX is used.

Two #2-56 x 1/2" screws with nylock nuts + some hot glue hold the Bind button and LED board in place. Two 1/4" holes, one for the antenna, and one for the Mode Switch. Check the instructions with the V8HT for other hole sizes of the Bind and LED board, note the offset of the parts from the mounting holes.
Last edited by Jsutherland8; May 24, 2012 at 11:49 PM. Reason: Add info
Sign up now
to remove ads between posts
May 25, 2012, 12:18 AM
Jsutherland8's Avatar


Test fit the Mod Switch before soldering wires on it. Pull it out and position 1" above with 3rd hand to solder wires.

Test unit with TX battery and RX's for both Modes, and range test.
May 27, 2012, 07:56 AM
Registered User
Cougar429's Avatar
Does the selector switch cut power to either the DIY module or legacy RF board?

When using 2.4 do you need to select PPM output in the parameters?
May 27, 2012, 08:33 AM
Registered User
Thank you, added this conversion in the Frsky main thread resources list
May 28, 2012, 10:59 AM
Jsutherland8's Avatar


Yes the output has to be set to PPM in the radio setup menu.

Yes the + voltage and PPM wires are switched, so only one RF unit is powered at any time.
Last edited by Jsutherland8; May 28, 2012 at 11:29 AM.
Jun 27, 2012, 07:48 PM
Registered User
Sep 30, 2012, 01:49 PM
Registered User
Can the trans still be used to buddy box after the mod?
Oct 02, 2012, 06:29 PM
Who let the dogs out?
Phil_G's Avatar
I did a similar Frsky mod to a 6EXA, not switchable, just 2.4g.
But instead of having the standard 2.4g aerial folded across horizontally like yours I mounted it inside the 6EXA handle:
May 24, 2013, 07:16 AM


Hi I have just read your posting on converting a Futaba 6EX 72 mhz to FRSKY 2.4 ghz, I am wanting to do the same to my T6EX 35 mhz,can you tell me if the conections and internal lay out is the same,IE can I do the same mod,liffting wires from the same lands as per your photos,Barry.
May 25, 2013, 02:47 AM
Registered User
Check Frsky main thread index, Migrations section:
Sep 01, 2013, 08:17 PM
Registered User
I just used your guide to covert one of my T6EX. I have some pictures here.

Thanks, John
Oct 13, 2014, 10:03 PM
Registered User
I'm new to this blog. I'm wondering if anyone can help me do the same converison on a futaba t6nfx which has one circuit board and a solid mounted trainer port. How do I identity the 3 contacts on the board to connect to.

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Sold Futaba 6EX 72 mHz Transmitter tinkerer1962 Aircraft - General - Radio Equipment (FS/W) 0 May 24, 2012 10:00 PM
Sold Futaba 9CAP 2.4 fasst + 72 mhz 300+shipping vic gensberg Aircraft - General - Radio Equipment (FS/W) 0 Mar 11, 2012 02:29 PM
Sold Futaba 14MZ 2.4 Ghz FAAST + 72 Mhz Ne-Aero Aircraft - General - Radio Equipment (FS/W) 2 Jan 09, 2012 07:06 PM
Question Can i connect UHF System to Futaba 6ex 72 mhz ? RanD222 FPV Talk 7 Nov 09, 2011 11:24 AM
For Sale 14MZHP w/ 2.4 FASST TX mod and 72 Mhz Tx mod rcgalore Aircraft - General - Radio Equipment (FS/W) 4 Nov 27, 2008 09:23 PM