CW and RTTY Transmit on Soundcard Modes

[koØm]

The “Rock-bound” portion of me needs a little help with the “Digital Radio" world. In the old days (FT-101E), if we were communicating in the AM mode on 3885 MHz and, we wanted to communicate on LSB then, I would have to switch my mode to “LSB” and QSY with the VFO to 3883.5 MHz to talk. On CW, I tuned the VFO until the receive signal had a certain tone and then, I knew I could communicate with the other station.

Today, my solid state radio (IC-706MKIII) (does or does not?) automatically offset for the different sidebands. This is important to know because of the layout of the “Channelized” 60 meter band; there is a carrier frequency and a allotted USB bandwidth; in simple theory if I can zero-beat him on receive I should be legally on “the channel”(?).

About the “Sound Card Modes” , I have them and, they work but, how and why? I’m on USB using a popular Ham Software program that comes with HRD and, I see a station on the Waterfall using PSK so I line up with him and we communicate -- no brainer. Next I hear see a station using RTTY , I switch the software to the RTTY mode but leave the radio in USB mode(?) to communicate with him?

There’s a station in the CW mode, I’m still on USB; if I change the mode on the radio the station disappears from the waterfall, take it back to USB and the signal is there.

To sum it all up, in the old days, I had to physically change frequency to transmit in different modes, today with the Sound card modes I don’t but, it is hard for me to grasp how I can leave my VFO set and, communicate on different modes but still be "on the channel”.

When you communicate a Net Frequency, are you using the carrier frequency or the sideband / cw / RTTY offset.

[X-Rated]

I am not sure about the IC-706MKIII. Usually the readout shows the carrier frequency. 60M is defined by both the carrier frequency and the center frequency of the sideband information, usually.

You need to check your manual.

[kb2vxa]

I have the Mk2G and I don't see why Icom would change anything, the only trouble is the readout says where the carrier SHOULD be, but if the MO is off the display is useless. The discrepancy increases with frequency, HF and 6M is accurate but on 2M SSB stations have told me I'm a few KHz from where I think I am. On FM it doesn't matter but on CW and SSB it's a big oops, I had to use my frequency meter.

It's really not hard to grasp if you visualize the transmitted signal. You know (or should know, hi) where sidebands are in relation to the carrier, so since a sound card produces audio tones once you know the frequencies of those tones you know where they are in relation to where the carrier would be. Since the readout, providing it's accurate, is the carrier frequency just add the frequencies of the tones and you have the RF frequencies they're on. The interesting part of digital software is reverse mode, everything is on the rig's USB setting, so if it displays gibberish try clicking on "reverse" and it should clear up.

[n0iu]

Next I hear see a station using RTTY , I switch the software to the RTTY mode but leave the radio in USB mode(?) to communicate with him?

If you are going to run AFSK RTTY using DM780, leave your radio in USB. Normally, RTTY is received using LSB, but Simon was kind enough to write the program to automatically put the RTTY program within DM780 in "REVERSE" mode so we could easily switch between the modes that use USB and RTTY.

Clear as mub, eh?

[koØm]

I have the Mk2G and I don't see why Icom would change anything, the only trouble is the readout says where the carrier SHOULD be, but if the MO is off the display is useless. The discrepancy increases with frequency, HF and 6M is accurate but on 2M SSB stations have told me I'm a few KHz from where I think I am. On FM it doesn't matter but on CW and SSB it's a big oops, I had to use my frequency meter.

It's really not hard to grasp if you visualize the transmitted signal. You know (or should know, hi) where sidebands are in relation to the carrier, so since a sound card produces audio tones once you know the frequencies of those tones you know where they are in relation to where the carrier would be. Since the readout, providing it's accurate, is the carrier frequency just add the frequencies of the tones and you have the RF frequencies they're on. The interesting part of digital software is reverse mode, everything is on the rig's USB setting, so if it displays gibberish try clicking on "reverse" and it should clear up.

EUREKA!

or

"Doh"

Take your pick; the bottom line here is that I have two Amateur Transceivers that operate differently. When I change the mode of operation on the Yaesu FT-101E, I have to move the VFO to set the display of the Yaesu 601 counter to the exact frequency that I want to transmit on; on the MK3G it is different.

When I change to either USB or LSB, although the readout on the radio does not change, the carrier is shifted up or down 1.4 KHz respectively according to the mode (Just like my Chicken Band Cobra 148 GTL).

It was a simple procedure to find the needed info; I transmitted into a "non-radiating" load with the ICOM IC-706 on SSB and used the Yaesu FT-101E on a local antenna to track where the transmit frequency was. I have a frequency counter but, it was not able to capture the frequency of the modulation envelope in Side band.

So, in my "Stone aged" interpretation, when my display says I am operating in PSK on the upper side band @ 7035.00 MHz, I am actually at side band frequency 7036.40 MHZ on the ICOM. Conversely, although the display on the ICOM says 7248 MHz LSB, it is transmitting on side band reference 7246.60 MHz.

The DM780 Waterfall makes sense since I now know where the side band is.

.

[kb2vxa]

Dohreka? That's one major problem trying to see sidebands on a frequency counter, it needs a steady "carrier" to read. Sidebands are constantly shifting frequencies and amplitudes that confuse the hell out of it. That's where you need some sort of scope frequency display to see them, or know your transmitter and input tones and visualize them on the scope of your mind. "The DM780 Waterfall makes sense since I now know where the side band is." That'll work, computers are smarter than some hams. (;->) Yep, you hit the the nail on the head, just watch your fingers or when you switch to CW you'll have a glass fist.

[koØm]

Dohreka? That's one major problem trying to see sidebands on a frequency counter, it needs a steady "carrier" to read. Sidebands are constantly shifting frequencies and amplitudes that confuse the hell out of it. That's where you need some sort of scope frequency display to see them, or know your transmitter and input tones and visualize them on the scope of your mind. "The DM780 Waterfall makes sense since I now know where the side band is." That'll work, computers are smarter than some hams. (;->) Yep, you hit the the nail on the head, just watch your fingers or when you switch to CW you'll have a glass fist.

When I was younger and stronger, I was able to whistle a tone long enough and strong enough to read the side bands; since I got out of CB, my whistling skills have lost their polish.

I only do CW on the Yaesu, it has the filter for it.

.

[X-Rated]

Seems like you should be able to

1. tune your rig to a SSB signal that is pretty much alone around on the band.
2. switch to the opposite sideband.

Did the signal go away and the digital readout stay the same? Then I would say your readout shows the carrier frequency.
Did the signal stay there but become garbled and the readout stays the same? Then I would say the readout is showing the center frequency of your sideband.
Did the signal go garbled and the readout changed? Then I would say your readout shows the carrier frequency.

I am guessing it is showing the carrier in one way or the other.

[w6tmi]

There’s a station in the CW mode, I’m still on USB; if I change the mode on the radio the station disappears from the waterfall, take it back to USB and the signal is there.

The rig is probably tightening the bandpass, so the signal falls out of the receive range when you click it to CW

[AC6AT]

So, in my "Stone aged" interpretation, when my display says I am operating in PSK on the upper side band @ 7035.00 MHz, I am actually at side band frequency 7036.40 MHZ on the ICOM. Conversely, although the display on the ICOM says 7248 MHz LSB, it is transmitting on side band reference 7246.60 MHz.

When you're operating in PSK with sound card software and the display on the ICOM says you're operating on 7035 kHz upper sideband, you are actually "at" 7035 plus the audio frequency that you've selected on the waterfall. So, for example, if you've selected (or generated) a signal at 1100 Hz with the software, your signal is at 7035 + 1.1 kHz, or 7036.1 kHz.