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[W6AOA]

My IC7300 Just started shifting down 1khz when I hit tune/OR transmit on WSJT-X.  Is there a setting i'm missing ??

[KF6QEX]

If next to the band the green circle has an "S" in it you are using split mode.
Settings->Radio->Split operation

Dimitri

[AF5CC]

Are you in Hound mode?

[WA9AFM]

Got to 'Settings', click the 'Radio' tab, look at 'Split Operations'.  Make sure 'None' is checked.

[K0UA]

Got to 'Settings', click the 'Radio' tab, look at 'Split Operations'.  Make sure 'None' is checked.

NO. DO NOT DO THAT.

Your WSJT-x is supposed to be in Fake it mode. Leave it in FAKE IT mode

Jeez o pete. is this so hard to understand? YOU WANT the rig to do this "strange frequency shift".  This is a GOOD feature. This places your audio frequency in the "sweet spot" of your modulator so there is not roll off on the ends either the high frequency end or the low frequency end of your modulator leading to a drop in transmit power. Again this is a feature you want to take advantage of. If it is disconcerting to see your frequency changing when you transmit outside of the middle of the audio frequency "sweet spot" then don't look at the display. It is doing exactly what it should do.. It is compensating with a change in carrier frequency when you choose a low or high frequency audio frequency on the waterfall so that your audio does not roll off.

[K0UA]

Do people really think that modulators on SSB transmitters have a flat response from 200 Hz to say 3500 Hz?  NO they do not. They roll off any time you get away from the middle of the audio input frequencies. So when you select your audio input frequency with WSJT-x to be 200 Hz, do you really think you can shove 200 Hz audio into a rig and expect the same RF output power you would get if you shoved 1500 Hz into it? Of course not. So the designers of WSJT-x came up with a method of overcoming the limitations of SSB transmitters. They just shift the carrier point frequency either up or down when the audio frequency is too low or too high and roll off is likely to occur.

  Sure some transmitters modulator sections are better at handling roll off than others, but there is absolutely no harm in shifting the RF carrier point and changing the audio frequency upon transmit to a frequency more in the middle of the response of the modulator, whether that particular modulator needs it or not.

The program has complete CAT control of the transmitter so it can shift the transmitter back and forth as needed. As well as it can shift your selected 200 Hz audio frequency up to say 1200 Hz just as easily.  The person on the other end will see your audio frequency as 200 Hz at the carrier point of say 14.074 as if all that RF and AF shifting never occurred. But your transmitter is now "flat" in is response because it has be "faked out" by the shifting. Hence "fake it".

[AF5CC]

James,

Does this work as well if the other station is using USB mode as opposed to DATA mode on receive?  What I mean is, the display shows the carrier frequency.  USB is above the carrier.  So if I shift below the carrier frequency to 14.073 by using "Fake It", will they still be able to copy me?  I think in DATA mode it is showing the carrier frequency which might be in the center of the passband, but I am more uncertain about if they are in SSB mode.

I usually keep my transmissions somewhere in the 900hz to 1500hz range and keep the "Hold TX Freq" box checked so it isn't moving all around when calling different stations.

73 John AF5CC

73 John AF5CC

[AC9O]

The frequency displayed is the carrier frequency. Add the audio frequency to that to get the actual frequency. Look at stations on PSKReporter, it's always above the carrier frequency. On my 7300, the center of the passband (about 1500hz) is in the middle of the waterfall.

A BIG reason to use FAKE IT is to reduce audio harmonics. On TX, the audio tones are shifted higher so any harmonics fall above 3000hz. If you transmit above 1500hz, you probably won't see a shift. I hear many stations transmitting below 1000hz and I can see shadows spread out on the upper part of the waterfall. Sometimes you can actually see the individual frequencies within the modulation.

I run my waterfall from around 200 to 3000hz. I find above 2600 is less crowded and more likely to get a contact. Assuming they also "listen" in that range.

I am pretty sure that if you don't expand your waterfall to all those frequencies, you may be missing out on callers and DX.

73
Paul, AC9O

[K0UA]

James,

Does this work as well if the other station is using USB mode as opposed to DATA mode on receive?  What I mean is, the display shows the carrier frequency.  USB is above the carrier.  So if I shift below the carrier frequency to 14.073 by using "Fake It", will they still be able to copy me?  I think in DATA mode it is showing the carrier frequency which might be in the center of the passband, but I am more uncertain about if they are in SSB mode.

I usually keep my transmissions somewhere in the 900hz to 1500hz range and keep the "Hold TX Freq" box checked so it isn't moving all around when calling different stations.

73 John AF5CC

73 John AF5CC

Yes, everything will be fine. The "data" mode (depending on how it is set up in the rig) just kills the microphone. If you run SSB mode and put audio in on rear panel audio connections, your mic will still be hot. This is BAD. don't do that. Listen long enough and you will hear guys doing that very thing. sometime curses in the background, sometimes laughter, sometimes TV set playing in the background. Dogs barking etc. Don't do that. And yes Fake It can help some with  audio harmonics., But OVERDRIVING is the cause of harmonics. Don't be that guy. Stop overdriving. The best way to adjust your audio drive is my method. It works with all brands of rigs and interfaces. Run power on the rig at 100 percent. Run Windows speakers (which drive the modulator of the transmitter) at 100 percent, run WSJT-x power slider at 100 percent. THEN adjust the internal transmit audio control from USB if you have it like for instance a 7300 which uses its own internal "modem" to a level so that the power output falls. Now no matter what you do with the program, or what happens to window or where you put the power output of the rig  you CANNOT overdrive the modulator because there isn't enough audio to do so. You have everything maxed out and the power output is NOT full so it cannot be overdriven.

If you don't have an internal modem, then adjust your signal link audio drive down till the power falls off. Same thing, doesn't matter what windows does because you set this up with windows speakers set to 100 percent. So windows cannot adjust them higher than that. Doesn't matter what you do with the WSJT-x power slider because you set this up with the WSJT-x power slider set to 100 percent. The ONLY way you can go is less audio drive. Remember the power output control of your rig is set for 100 percent. If you want to run less power than 100 (or 90 something because you adjusted the system to "fall off") then adjust the power slider on WSJT-x.  The only way you can adjust it is down, because if you adjust it for 100 percent, the rig will STILL not be fully modulated. And that is where you want to be.
Understand that if a rig is not quite fully modulated no matter what you do or windows does, then it CANNOT be overmodulated. You just can't get there.  Of course it follows that you don't touch the transmit audio from your analog interface going into your rig or don't reprogram the audio input level in your modern transciever like a 7300, because if you do, then you could have the overdriven problem. Watching ALC meters is a waste of time in my opinion because they all work differently, My Method works for all rigs all of the time, and is easy to understand.

[K0UA]

Some of you may have noticed that many times you only be able to work as station by transmitting audio close to where they are transmitting.  The reason is they are not making use of panoramic reception. There filters are often set narrow.  If I had a dollar for every guy I have asked "what is your filter set for?" and they have said "what is a filter?" I would literally have a fist full of dollars.

Many operators, and it doesn't matter if they have been licensed 50 years or yesterday, have NO IDEA what the filters in their modern rigs do, how to use them, or even why they would want to use them. One of the things the 7300 (and when I use that as an example I mean all modern rigs, regardless of brand or model) is have a "set" of parameters that go with a particular mode. For instance the filter settings are context sensitive, So if you are in SSB mode the filter settings can be different than if you are in USB-D or so called "data mode. If fact more complex rigs like my 7610 will have DATA 1  DATA 2 and DATA 3 modes.  You can make the filters anything you want. And they can all be different.

 Remember this is a "software defined" radio and the setting are defined in software. In using WSJT-x for FT modes you typically want your receive filters to  be set as wide as they can go. In the Icom rigs that is from about 100 hz to 3.6 Khz.  Some modern rigs will go wider. The problem is people tend to cluster up around 1500 Hz, and the smart ones will venture closer to the edges BUT they still have go work guys that don't have a CLUE to what their filters are set for and don't know how to set them, and are just happy as clams working from around 1000 Hz to maybe 1900 or 2000 or so. "it has always worked for me that way."  So you call them at 500 Hz and they don't hear you because their filters are not set up correctly.  The smarter of the bunch start to wise up and do eventually figure it out. But many never do.

 In my opinion it stems from the fact that Older not modern rigs had a single SSB filter in them, of maybe 2.4 or maybe 2.8 and if they paid for it had a CW filter in them.  They could not "set them" to what they wanted, they just had to accept what ever was in there and that was that, and never gave it another thought.

On modern rigs you set the SSB filter to what ever you want,  and you typically have 3 settings for each mode. So SSB1 maybe at 2.8 for wideband ragchew audio. one set for 2.4 for normal DXing contesting and one set for 1.9 for when things get really crowded and bad and you will be willing to accept lousy audio response to help eliminate QRM.  Of course the twin passband dynamic filters do the same thing except on a dynamic "right now" basis and also let you shift the passband up or down by grasping both knobs and turning them in one direction.

 Remember you are just controlling the software, you ain't moving some mechanical thing. Just pop the Twin Passband Tuning knobs in the nose to instantly reset it to centered and normal bandwidth as selected by the particular filter. Of course this works this way for CW, RTTY and Data modes. All the preset filter settings go along each time you call up one of these modes.

Aren't SDR's Grand?

[K0UA]

Now I have typed a lot of word's, and some of you don't like that. BUT.

If any of you learned even one little thing from all the words that spewed out of me, then my day is complete.

[W9IQ]

Now I have typed a lot of word's, and some of you don't like that. BUT.

If any of you learned even one little thing from all the words that spewed out of me, then my day is complete.

Your post is "sticky" worthy, James. Thanks.

- Glenn W9IQ

[K0UA]

And just to add a cherry on top of the whip cream on top of the icing of the cake, ALL of those filter settings and scope settings etc. are saved to the SD card in your 7300 (and/or USB stick on the 7610) when you save your parameters. You do have and SD card in your 7300 and are doing periodic backups aren't you?  You should be. And you should take that SD card or USB stick and put it into your PC and back it up there and the cloud so when lightning makes a charred hole in the middle of your previously shiny rig, when you get a new one, you can download all of that wonderful setup you spent hours "tweaking" to just how you like it right back in about 10 seconds.

You can also e-mail your setup to freind so he doesn't have to spend all that time setting up. AND/OR you can keep dozens/hundreds/thousands of setups on that SD card/stick or on your pc and load them into the rig in seconds.  Now how many of you knew all of that?  All of the Voice memory's and CW memories and RTTY memories can all be saved and transferred around too. Do you know you can work a whole RTTY contest and save it to the  SD card to be seen at your leisure on a PC?  Can be used as proof of working etc. For that matter you could do the same with a Voice contest too. You can record anything you want, including both sides of the QSO if you want.

Again, aren't SDR's grand!

[KF6QEX]

You can record anything you want, including both sides of the QSO if you want.

Much easier than having to flip the open reel tape over


Dimitri

[K0UA]

You can record anything you want, including both sides of the QSO if you want.

Much easier than having to flip the open reel tape over


Dimitri

Not to mention making a convenient file you can save to PC/Cloud  and can email to the other guy or anyone you want.  The e-mail thing only works if the file is not to large to pass thru the email server. But there are dropboxes and I have even set up password accessed cloud partitions for people to download files from my cloud storage. I can remember talking to an amateur in England and he had a youngster that had never talked on a radio before and put him on the mic. I sent the recording and they were delighted to have it.