JT-9 operating tip - TX bandwidth

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Now that JT-65 and JT-9 are gaining in popularity I thought I would pass along a tip to avoid a problem I ran into tonight.

While operating WSJT-X I tried replying to a station running JT-9 @ 2900 Hz. My power out was 1/4 of what it should have been, resulting in poor signal received by DX station and retries.

I noticed I had DIGI-U TX bandpass set to 100 - 2900. I opened it up to 100 - 3100 and made two more contacts tonight @ 2900 Hz with no drop in power from where I have it set. The two stations I contacted at 2900 HZ were -26 and -28 signal while my report was at least 10 higher. They are probably using radios limiting their TX passband (modern Icom is 100 -2900 Hz)

So the tip is to check your TX bandwidth if planning on JT-9 mode.


73

Dave wo2x


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David Decoons wo2x, Elmer

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Posted 3 years ago

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Kent Olsen

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David

Thanks, that is a good tip!

Do you have AGC turned off while using WSJT-X?

Thanks
73
Kent
NC6B
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Ian GM4KLN

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Sorry but I don't agree: I think a far better way is to use the "split" functionality within WSJT-X, which places your TX in the middle of your TX default passband...thereby helping to reduce the opportunity to TX harmonics...and indeed away from the skirts of the TX filters. 
Works like a dream....
As to AGC - I run with that off at all times.
73, Ian GM4KLN
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David Decoons wo2x, Elmer

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Have you tried setting radio choice to Flex 6xxx and using the TCP connection? Then set WSJT-X to use radio split? It tries to open 4 slices on my 6700 and crashes with a Hamlib cannot get radio frequency error.


If you have it working please let me know.

Dave wo2x

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Kevin

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I use Fake It to achieve what Ian is referring to and it works perfectly. No concern about audio harmonics, dropping power at the edge, extra slices. It puts my  audio between 1500 and 2000 Hz every time.
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David Decoons wo2x, Elmer

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Thanks Kevin. I will try Fake It. I keep getting Hamlib crashes when trying to use Radio.

The main point is some users may not realize as a default that JT-9 could put the transmit signal on the edge or even out of their transmit passband.

73 Dave wo2x

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Ian GM4KLN

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Hi Dave
Running 6300 here. Which version of WSJT-X are you using - I know there were some additions done to the Hamlib relatively recently to acommodate 6xxx but not sure they are within the "released" version - think only within those you compile yourself. May be wrong here.....will check when I return home this evening
Thanks Kevin - Fake it is indeed what I meant :-)
73, Ian GM4KLN
(Edited)
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Ria - N2RJ, Elmer

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I do not use TCP/IP. I use CAT and set it to TS2000. Faking it works perfectly OK. I could never get TCP/IP to work. Yes, it's cutting edge but I never got it to work. 
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Kevin

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Have you tried it with the latest version of WSJT? Haven't had a problem with it here. Not certain there's any real advantage.
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David Decoons wo2x, Elmer

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TCP works fine here using Fake It. You need to create a TCP port in CAT (I use 5004)

Then set WSJT-X Flex 6xxx port to 127.0.0.1:5004
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Jay / NO5J

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Ria

Could I volunteer to help you, with getting TCP/IP Cat working for you with WSJTX-1.7.1 and SmartSDR v1.10.15?

Using TS2000 with regular CAT is perfectly OK. I just don't see any reason to leave you behind.

So If you're willing to have another go at it, maybe I can spot the problem.

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  73, Jay - NO5J

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Ria - N2RJ, Elmer

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Interesting. What advantage does it get you other than being new tech?
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Ria - N2RJ, Elmer

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Hi Jay, thanks for your very kind offer but I followed what Dave said to do and it works. I was under the illusion that it would connect direct to the radio rather than use the CAT app.  (Thanks Dave, see you Friday?)
(Edited)
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Jay / NO5J

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Ria
 
No real advantage yet, WSJTX, and Hamlib3 don't speak Flex API, so they can't connect to the radio directly. They only speak CAT. The radio only speaks Flex API, SmartCAT is fluent speaking either, so it's doing the translating. The SmartCAT client isn't limited to CAT over serial connections. So as you say, TS2000 is already working 100%, so there's nothing to be gained by switching to a TCP/IP port. Both options work. Having more choices is a good thing!

I've noticed that physical serial ports are disappearing from many motherboard chipsets. Firewire went through the same thing, ethernet is replacing it. What we don't use, we loose, also what we don't use, and/or support in software development might not produce further development. That could become a disadvantage.

I think of it as future proofing my existing hardware.

And I really like shiny new things, especially when they are free!

Support the Future! 
It ain't going away.
It's headed this way.
Just don't get run over.
Get onboard and ride!
Heck, I want to drive!

We paid for the privilege already when we chose our Flexradios.

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(Edited)
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Ria - N2RJ, Elmer

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I agree and I honestly don't miss the endless nest of serial ports connecting every which ways from Sunday. I do have 6 PCIe serial ports, however. Wondering what to do with them, probably just going to remove them from the tower. I do need to keep 2 for rotors but that's about it. 
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Jay / NO5J

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Ian

The changes to Hamlib3 for the 6300 model were added after the WSJTX v1.7.0 release happened. The 6500, and 6700 models were included as part of the v1.7.0 release.

I'll include you in my help offer, though.

Take a look at this thread. ...

https://community.flexradio.com/flexradio/topics/beta-and-wsjt-x

Which might help.

If you're not short on hard drive space and want to try using JTSDK to build WSJTX v1.7.1 alpha source, I'll offer to try to help with that too. The only advantage in doing that is that you don't have to wait for the next GA release to hit the street. 

Is it worth it? That depends on how much you like waiting, I suppose.

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  73, Jay - NO5J

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Jay / NO5J

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It is getting harder and harder to find motherboards with parallel ports, and firewire in their chipsets, too. Adapter cards are "still" available, I buy 2+ of almost everything lately, I'd prefer to drive my PC's into the dirt. but I'm beginning to think I need to plan on new machines whenever any of them dies. I try to keep 3 generations of hardware actively doing things. When the oldest dies it will be time for a new newest. My spare machines were bleeding edge when I assembled them. Now they're closer to the dying edge. Up to now, my SDR1000 can still be used with any of them. I'm going to ride that rig into the dirt too, or at least until the dirt catches me. 

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Ria - N2RJ, Elmer

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I don't need the LPT ports anymore. I used to use a top ten DX Doubler by N3RD but since I got the 6700 I don't need it anymore. I am not even sure what I would use it for, to be honest. The BIT and BCD outputs from FTDI USB adapters connected to the radio will work for switching filters etc. However when I was running a conventional radio setup I actually used the CI-V/CT17 setup with a pcie serial port because I couldn't find a USB adapter that didn't shut down when it got a little bit of RF. 

This PC I have now was a birthday present, actually, about 5 years ago, still going strong with a SSD and more RAM. Still no serial ports. 
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Ian GM4KLN

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Hi Jay
thanks for the comments and kind offer, but I'm already using v1.71 r7486 which I self compiled - managed to blunder through the process :-)
I was just not sure whether the 6300 code had been included in the release version and as your link to another thread confirmed, not yet, but there's a work-around. I just couldn't remember yesterday when I was away from the shack. 
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Ian GM4KLN

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Hi Jay
thanks for the comments and kind offer, but I'm already using v1.71 r7486 which I self compiled - managed to blunder through the process :-)
I was just not sure whether the 6300 code had been included in the release version and as your link to another thread confirmed, not yet, but there's a work-around. I just couldn't remember yesterday when I was away from the shack. 
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Jay / NO5J

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Ian

The changes for the 6300 model missed the WSJTX v1.7.0 release by a few days.

The 1.7.0 GA release occurred on 12/19/2016 using -r7405.

WSJTX v1.7.1 r7486 should already include the 6300, hamlib3 changes. So it ought to work as is.

 The change in Hamlib3 was committed on 12/24/2016,  Which was Hamlib3 Commit [10eb19] .

So any WSJTX builds done after Christmas, should include TCP/IP CAT for the 6300, any revision past -r7426 actually. 

WSJTX v1.7.1 r7486 was available beginning 1/12/2017. 

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(Edited)
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Ian GM4KLN

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Thanks Jay - good info: that's nice and clear. As I suspected then....
I've just started using DXLabs so will re-configure and try 6300 "native". 
73, Ian GM4KLN
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Jay / NO5J

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Ian

If you haven't already, then be sure and look into the DXLabs-Fldigi-Gateway.

http://www.n2amg.com/software/fldigi-dxlabs-gateway/ .

It will set you up to log Fldigi directly into DXKeepers log.

For WSJTX, JTAlert does the same thing and a lot more.

http://hamapps.com/

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(Edited)
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YV5WZ

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I've been doing JT65 & JT9 with WSJT-X software, actually: 1.7.0 r7405
DIGI-U TX bandpass set to 100 - 5000 and RX 5K, Slip operation: None 



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Rob Fissel

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FWIW, I always use an RX bandwith of 0-5000 hz for JT modes on HF. For example, I've seen stations before where their VFO was at 14.078 for JT9, transmitting at 2500 Hz - that's 4.5kHz up from 14.076. I've worked many stations this way - it's nice to be able to monitor ALL of the JT65 and JT9 occuring at any given time. Also, as others have mentioned, I use fake it to keep the TX around 1500 Hz no matter where the signal lies within the RX passband. 
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Jay / NO5J

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Rob

I have created custom SmartSDR memories for both 4k and 5k filter widths I just save them and then delete the saved frequency field. that way I can quickly use a 4k or 5k width on any slice, no matter where I'm tuned. I have a neighbor fairly close by that operates rtty inside the agreed JT9 assignment, and I can usually exclude his 40 over signal from my AGC passband by dropping back to a 4k passband. I also have separate 2k memories setup for both JT65 at #.076 and JT9 at #.078
That I can switch to when I don't want to operate both 65/9. I also prefer to use fake it. 

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