Question on RTTY, FLDigi, and 6400

Pat_W5WTH

I saw all the RTTY sigs and thought I would give it a try.

When I put my 6400 into RTTY mode the audio tones are so high pitched that by are not even on the FLDigi waterfall (tops at 2KHz). If I switch the 6400 to CW mode the RTTY tones lower in pitch and I can see them on the FLDigi waterfall and they have the correct tone spacing on the waterfall (meaning I can align the FLDigi waterfall tuning marks to the sig).

What am I doing wrong here?

Thx,

Pat - W5WTH

Ted VE3TRQ

When I use Fldigi for RTTY, I use DIG-U or DIG-L. But then I’m not a serious RTTY type :-) Ithink RTTY should still be created with devices that smell of oil.

Neil D Friedman N3DF

Gave up my 28-ASR for HAL solid-state gear 50 years ago.

Pat_W5WTH

OK. Pouring oil on the whole works now. I will wait for that vintage oil smell and try again, but I am not hopeful of the results.

Pat_W5WTH

All right. The shack now smells of oil and is a huge mess. :) No change.

Also, the DIG-U suggestion did not yield as well. I will clean things up and wait for more input from other.

Thx!

K0FLY

The tones that most amateurs use are 2125 and 2295 (High tone set). Some of the older TUs of the 60/70s used AFSK osc. that were rich in harmonic content. The high tones were chosen so that the 2nd harmonic of each tone was attenuated by the SSB filter. As long as you maintain a 170 Hz shift you can use any tone set you want.

Go to the Flex "Settings" drop down menu then "Radio Setup" On the Radio Setup screen click on the "Phone/CW Tab".

Change the RTTY Mark Default setting to a lower frequency. You should now be able to see the RTTY signals on the FLDIGI water fall, or if you spread the FLDIGI screen to a wider width on your monitor you should be able to see signals out to 3500HZ and copy signals with the Flex Mark frequency set at the default 2125 .HZ.

My wife has a little fragrance device that uses a 4 watt bulb to heat the fragrance oil, I just replace that oil with Three in One house hold machine oil. Brings back the Model 15 smell when I'm on RTTY.

Gayle K0FLY

K0FLY

Second comment. At the bottom of the FLDGI screen there are some control buttons, the set of buttons that slew the center frequency of the water fall higher or lower. Center the Water fall on 2000HZ. You should be able see the RTTY Tones displayed with the Flex in RTTY MODE.

Pat_W5WTH

BOOM! Thanks, @K0FLY ! Nailed it!

Pat / w5wth

Erika - KØDD

Whatever you do don't press and hold the orange and red buttons no matter what anybody says. It will send shift g until a fuse blows.

Pat_W5WTH

My chances for weekend RTTY contest fame has passed and I still haven't managed to sort out my FLDigi/6400 problems.

@k0fly, the Rx is fine thanks to your tip above. The Tx, well, not so much....

With FLDigi and the 6400 in RTTY mode the rig keys down (MOX and red power button) when I ask FLDigi to send a message. The TX Stream on DAX button is blue and I can see from the red "VU" meter in DAX that audio is being produced. But,,,,,,, I get no modulation on the 6400. The same thing happens if I switch the 6400 to CW mode, BTW. However, if I switch the 6400 to USB mode (leaving all other settings the same) I can tell that when I ask FLDigi to send a message it works. I can see modulation on the bandscope in USB mode.

Any idea what I am missing? I feel like I am close to RTTY greatness.

Thanks,

Pat / w5wth

K0FLY

You problem is PROBABLY in the SSDR control panel P/CW Pane, is the "DAX" button blue when in the DIGU mode? This has bitten me before.

Gayle K0FLY

K0FLY

It was late last evening, I should have said RTTY mode. SSDR control panel, Is the DAX button Blue on the P/CW pane.

The DAX button enables the signal from the DAX to modulate the TX.

Gayle

Pat_W5WTH

NOTE: These TX test were done into a Dummy Load.....

@K0FLY , Thanks. I followed your meaning on your post and I had confirmed that. Two screenshots. DAX with TX Stream On(note Red "VU" meter due to Tx) and +DAX with SSDR On.

OK... when I hit a transmit message macro in FLDigi the 6400 keys up (MOX on and RED LED).

Nowhere on the bandscope do I see any modulation on the sig. It's look like a dead carrier. But.... when I change the 6400 into USB mode I see the modulation on the bandscope when I press a transmit macro. See:

I'm still stumped. I get no modulation in RTTY mode (or CW mode, for what ever that is worth). Thanks for helping and I hope this generates a new 'thing' to suggest from you or someone else.

Pat / w5wth

Chris DL5NAM

Did you try switch F6 to Mode : RTTY ?

Chris

Chris DL5NAM

Sorry, i was to fast - yes you have done

K0FLY

You have modulating audio to the transmitter, OK. Your TX filter and EQ setting could be attenuating your transmit signal. Now with your "RTTY Default profile selected, look at the TX filter low-high cut frequencies , its adjusted on the SSDR control panel, "PHNE " pane. The hi/lo TX filter frequencies are are memorized in each profile so with your FHM-3 mic profile you TX bandwidth is OK. Also look at your EQ settings, mine are set at flat for DATA modes. My data TX filter is set at 100 lo and 3000.hi.

I ran into the filter problem back with version 1.xx software. The TX filter somehow was changed to 1600 low and 1650 hi, resulting in no SSB TX. CW worked fine

Gayle

KD0RC

Hi Pat, is FLDIGI expecting your Flex to be in DIGU instead of RTTY mode? Ted addressed this the other day. I have not researched this, but from my old RTTY, AMTOR, PACTOR days, I would expect RTTY mode to key using the key line on the accessory connector (FSK) and software generated RTTY (AFSK) like FLDIGI to be sent via DAX and therefore need DIGU or DIGL.

Pat_W5WTH

GOOD NEWS.... We have a WINNER. Thanks @K0FLY for your suggestion of: "I ran into the filter problem back with version 1.xx software. The TX filter somehow was changed to 1600 low and 1650 hi, resulting in no SSB TX. CW worked fine"

My LOW/HIGH cut was blocking the RTTY. I changed it to 100/3000 and all is well.

Now all I have to do is find someone doing RTTY on a non contest day to test it. :).

Thanks again to all that helped!

Pat / w5wth

K0FLY

Pat:

Glad you got it running. I didn't know you are in Austin. I was stationed at Bergstrom 1968 to 1970. I liked Austin a lot.

Gayle K0FLY