Bad Transmit Signal

Mike KD2CJJ

take a look at the pics.  I'm having a bad transmit.  Should I try to reset the unit?


The issue is across all bands...

Mark Gottlieb

Is this Version 1.5?  If so, I would try deleting and reloading version 1.4.  There is a community thread in progress regarding a distorted, corrupted transmit signal with version 1.5.  FLEX is working on the solution.

Mark
WA2DIY

Mike KD2CJJ

I tried resetting doing everything.. its worse on 6M through 17 Meter.  20M isnt as  bad but still present.  Im at a loss.   I have never seen this before.  yesterday the only thing I did different was do a calibration - which I have done in the past but not in a while.  And that doesnt work either. Unit is how 4 weeks old!

Mike KD2CJJ

Its 1.5.1 - the latest version which is suppose to fix that problem!

Mike KD2CJJ

PS - my unit came with 1.5 if I remember correctly.

I upgraded the moment 1.5.1 came out.

Mark Gottlieb

It should not be a hardware issue.  Version 1.5.1 should have the correction in the software that will solve the problem and that is a free download on the FLEX website.  If that doesn't solve it, download version 1.4 or 1.4.16 and see if that fixes the problem.

Mark
WA2DIY

Bill -VA3WTB

When all this started, Flex began looking for the problem and found it, they fixed the problem in 1.5.1

Mike KD2CJJ

Yea.. well Im running 1.5.1!

Guess they didnt!

Bill -VA3WTB

something eles going on then, I would open a help ticket.

RoyS

Mike,
Open a help desk ticket. Take the time to give as much detail about the problem as you can.

Roy - W5TKZ

Ken - NM9P

A cold reboot is always a good first step. So is totally closing Dax and reopening.

Mike KD2CJJ

I did not try rebooting my PC - I did however trying power cycling the unit and resetting the persistence DB (hold down power button till its white).  That did not help.

I will see a recycle of my PC helps.

But why would that help?  I thought transmit all happens within the radio and the PC is just a dumb client?

Help Desk ticket submitted.

The only thing I did different very recently (yesterday) was do a calibration - which doesnt work clearly.  

PS - now I know why no one could hear me during the contest - even with my 1kw amp on.  I was constantly being asked what my call sign was after much repeating.  

Bill W2PKY

Hello Mike Sounds like a good time to try the FDX feature to hear your transmitted signal. See if the distortion is present at low power levels and if not increase power to see what happens. I have had issues with RFI getting into the earphone circuit that caused distorted audio. Good luck I'm sure you will find a fix.

Mike KD2CJJ

I spend probably 2 hours yesterday tweaking my transmit audio because of the very poor results on the contest (many many time I had to say my call - with my FTDXF i never had this issue)...   The audio sounds pretty good even with the default profiles.  However I suspect the issues were there as I was having significant issues during the contest.

The issue is not as apparent under 20 watts... on the XVR port we are pushing less than 1 watt.

Rob Fissel

DAX gets wonky for me too every once in a while. Shutting down all associated software (DAX/CAT/SSDR, Log4OM, WSJT-X, FLDigi, CW Skimmer... basically anything tied to SSDR software) usually fixes it. 

Side note, Ken. Have you noticed in 1.5.1 anything strange about DAX VOX? When I first start up after a reboot, or restarting software/hardware, VOX won't trip when using a DAX source for somthing like JT-65. I find that I have enable TX so that audio is flowing, and click MOX on and off a few times. After that, VOX starts to trip as expected. 

Mike KD2CJJ

Can anyone post a comparative screen shot of their 6 meters and 18 meters using the Tune Function at 100 watts into their antenna?

I dont know what a clean signal should look like and thus that would help me.

Ken - NM9P

Rob, I haven't noticed that particular VOX issue, since I don't use VOX for Digital modes.  I use CAT commands or hardware COM to Key PTT. 

I do know that if you engage DAX while in SSB mode that VOX does not work on the mike inputs.  I wish this was a selectable option.  When I am contesting and using the voice keyer program I cannot use VOX from my mike.  I wish I had the option to engage vox in SSB/AM/FM modes when DAX is active.

I understand why they don't have it engaged in DIGI modes, because you don't want to sneeze or holler at your cat while working PSK31 and have your voice transmitted all over the digital bands!

Ken - NM9P

Cal N3CAL

Mike,

Here is a quick snapshot of my 6300 tune on 17M.  Looks almost the same. 

 

Note:  I've been having TX issues with 1.5.1 also.  Trouble ticket has been generated but no resolution yet..

Cal/N3CAL

Jim Best

Got the same problem. On SSB I still have an ugly looking display somewhat like the old one. I'm not sure if it's just the display or if the signal is actually that wide.

Mike KD2CJJ

Cal... Dudly is eluding to that this is a normal signal. He said he will get back to me with a definantive answer. I'm no expert so I could not say. Thanks for the image. I feel better to know normal or not I'm not the only one.

Mike KD2CJJ

Any update on your ticket Cal? Not too much here. Now just was told its maybe an issue by dudley....

Cal Spreitzer - N3CAL

Mike,

My issue appears to be only when using DAX (DIGU) with my 6300.  Flex has told me they are adding a fix to the next release of SmartSDR (v1.6) that manages the DAX ring buffers better, preventing this from happening and lowering the propagation latency through the DAX ring buffer.

I've sent my 6300 back to Flex and they are allowing me to upgrade to a 6500 which will better suit my needs.  Flex has top notch customer service! 

Cal/N3CAL

Dave Dave

6300 here on 1.5.1 and my signal same settings looks on the display very good, very different then ones posted here.

Same settings as far as I can tell with pix posted.

Mike KD2CJJ

Dave can you post an image?

Douglas Maxwell

I am running SSDR v1.5.1 and have a cold start issue with the FPGA which results in distorted TX audio which can be immediately identified (when zoomed out to view whole band 200KHz or so of any band) by seeing multiple evenly spaced spurii of diminishing magnitude from the centre transmit frequency. If you see spurii at or below -100dBm then this isn't a problem. When you see evenly spaced spurii at a much higher level than this during transmit then you have this problem. I have monitored my audio with another trx when this happens and it sounds garbled/digital. Not all 6300s behave the same due to Process Voltage and Temperature. FPGAs are manufactured/bought by Flex in batches from Xilinx, each batch behaves slightly different from the last and designers are meant to ensure sufficiently tight timing constraints are placed on the firmware design to ensure the same behaviour across these batch variations. I recon my cold start problem is due to a firmware interface calibration that is only carried out at startup. It seems that this calibration on my radio fails without the user being alerted and allows severe crud to be transmitted over the entire band....very embarrasing! The solution is that you never transmit on first power on, instead re-start the 6300 then operate as normal. My 6300 always shows dirty tx on cold start, then perfectly acceptable tx after a restart. I have only owned my 6300 for 3 weeks or so and it came direct from the factory. I downloaded the latest SSDR version and upgraded the firmware to the latest so my problem is very current. Flex know about the problem but things have gone awfully quiet from support. I am very dissatisfied with the situation, but realise that many 6300s out there are operating trouble free. Anyway I thought I'd spell out my problem and findings to others that may have the same problem. P.S. My restart fix works with a 100% success rate so far. I imagine this is due to the calibration on re-start being successful as now a warm FPGA (as heat changes interface timings). Anyway YMMV.

Dave Dave

Dave Dave

Here you go, least I think its a normal signal however when I monitor it using FDX its almost too perfect on display.

Douglas Maxwell

Cold start result, tuning into a dummy load with 10w...-40dbm level spurii.

Douglas Maxwell

Warm start result, tuning into a dummy load with 10w...-95dbm spurii.

Douglas Maxwell

Both above pictures show the same portion of the band and the same magnitude range..just that the second picture is the result of a restart of the 6300. Welcome to my world!

Mike KD2CJJ

Doug that is pretty bad -  both dont look like clean signals to me.