Flex 6400 and an MFJ wide range tuner.

KG5PTE

I have put up an Alpha Delta DX LB Plus Inverted V dipole antenna. Which requires a a wide range tuner. For tuning SWR higher than 2.9. I know the Flex built in ATU may not tune like a wide range tuner. I already own a MFJ auto tuner and use it with my Icom 7300. I do not think that MFJ makes a tuner to radio control cable so how do I proceed ?

Thank you.

Geoff AB6BT

I use a Drake MN-2700 tuner...yes, it is manual. I also use a Drake L-4B, also manual...

Perhaps I should start a go fund me so I can afford all the new automatic stuff.

KD0RC

Hi James, I would start with the internal ATU and see which bands (or portions of bands) it will tune. You might get better results than you expect.

If the internal tuner just doesn't match well enough, then bypass the internal tuner and use your MFJ tuner. You don't mention which model tuner that you have, but there might be a pre-made cable that works. The Flex uses a subset of the Kenwood CAT commands.

Until you figure out the proper cable, just do a manual tune whenever you change frequencies by more than 10 kHz or so. You will need to press the Tune button on the radio, then the tune button on the tuner.

KG5PTE

I have the MFJ 993B Intellituner and I have a manual tuner a VCI Vectronics Model HFT1500.

Thank you.

John KB4DU

The flex does not support a cable to activate an external tuner whereas Icom does. The flex relies on sending a tuner level carrier to activate a wide range tuner. I use an MFJ 929 with the flex 6400 and the combination works well. Tune power on the flex is set at 10 watts. A press of the tune button allows the 929 to quickly access its memorized settings. I’m not at the rig until Tuesday so I can’t provide the MFJ tuner settings before then.

KD0RC

It looks like the MFJ 5124 interfaces the tuner to a variety of rigs. I don't know if it can be made to work with Flex 6000 radios. It might take an interface to the interface to get the RS-232 signal to an FTDI-based USB converter that the Flex can use.

I just thought I would mention it here in case someone else has used it successfully and can give some guidance.

Lionel

Some time ago I looked to interface my 993 with my 6400 and as I recall there is no data from the 6400 ports to activate the tuner. I just set tune power to 10w and the tuner does the rest typically with a couple of seconds.

KG5PTE

Does anyone use a manuel tuner with a Flex ?

KG5PTE

My MFJ 993 Intellituner uses a MFJ 5124I data cable between it an my Icom 7300 so when I turn on the tuner then turn on the radio the auto tune sequence starts. automatically.

KG5PTE

Ok Today I took some SWR readings on the 20 meter band using my Rig Expert AA 54 antenna analyzer. On the 20 meter phone band I have. 14.150 SWR 3.2 14.225 SWR 2.6 14.350 SWR 1.7 So I do not think the Flex 6400 ATU will work On 20 meter digital modes I have SWR ranging from 3.2 to 4.0 I have not tested 10 m or 40 m yet. (I not even worried about 75 or 160m)

Thanks

eltejada

@"John KB4DU" Do yo mind sharing the settings on the MFJ-929? I have the same combination (6400 + MFJ-929) but I have not been able to make the MFJ-929 to automatically tune when I click the TUNE button in the smartSDR screen. Any advise would be appreciated. tks!

John KB4DU

I should be back at the rig tomorrow.