Posts Tagged ‘Digital modes’
What Got You Interested in Radio? What Hooked You? (Story Time, with Video)
What got you interested in radio? What hooked you?
I’ve been asked, “What got you interested in radio, space weather, and the science of radio-wave propagation?”
Here’s a short answer as to why (and when) I became a radio enthusiast. It all started…
[embedyt] https://www.youtube.com/watch?v=0XBth62JgwA[/embedyt]
https://www.youtube.com/watch?v=0XBth62JgwA
The following picture is of my first shortwave radio, discovered in my home sometime between 1971 and 1973: a Sony portable transistorized four-band radio receiver. This was my very first shortwave radio (well, truthfully, it was my dad’s). This radio is responsible for my love of radio, electronics, and communications.
I still use this, sometimes, when listening to late-night AM-broadcast-band-radio DX. It is horrible for shortwave radio listening, as it has no noise blanker. For MW (Medium-wave) AM Broadcast DXing at night, it is excellent. The internal bar antenna is very directional so I can rotate the radio around until I get the best reception of some station. Back when I was a child, that made the radio very fun to use.
This next radio is a really capable military surplus radio circa WWII or shortly after (the late 1940s, early 1950s). This radio was my world starting around 1975. From Medium-wave to Shortwave, this radio could hear a pin drop around the world! Many late nights when I was supposed to be sleeping, I was up with the light dimmed and the tubes singing signals from exotic places.
What is your story?73 de NW7US
Addendum:
https://www.youtube.com/watch?v=y8bBM9Dy38o
[embedyt] https://www.youtube.com/watch?v=y8bBM9Dy38o[/embedyt]
Demonstration: Using FLDigi to Communicate with Olivia Digital Mode on Shortwave
Are you interested in starting out with the amateur-radio digital modes on the high frequencies? Have you heard of FLDigi? FLDigi is a software control and modem suite that interfaces with your transceiver, your computer sound card, and other input/output interfaces so that you can receive and transmit one of many digital modes. For example, FLDigi allows you to operate using the Olivia digital mode.
Unlike the JT/FT digital modes–modes that do an incredible job under marginal propagation conditions–there are other modes that offer keyboard-to-keyboard conversational QSO opportunities that can overcome rough shortwave radio propagation conditions. (The meaning of QSO on Wikipedia: An amateur radio contact, more commonly referred to as simply a “contact”, is an exchange of information between two amateur radio stations.)
While making quick work of getting DX stations into your logbook by exchanging callsigns, a signal report, and a grid square, the JT/FT modes (JT stands for Joe Taylor, the fellow that pioneered these modes) are limited. They cannot handle any additional communications beyond a callsign, a signal report, a grid square, and a very limited set of acknowledgments and sign-off messages.
When you desire to get to know people from other areas of the world, or if you need to establish networks around the world for passing information–perhaps an emergency net in support of the Red Cross–or if you are motivated by any other of a myriad reasons to establish a keyboard-to-keyboard conversation by way of the ionosphere, modes like Olivia are great candidates for your consideration.
In this video, contributing editor with CQ Amateur Radio Magazine, NW7US shares some starting points in the FLDigi software for Olivia keyboard-to-keyboard chat mode.
[embedyt] https://www.youtube.com/watch?v=ejSNfXiT8FE[/embedyt]
Current CENTER Frequencies With 8/250 in MHz:
1.8269, 3.5729, 7.0729, 10.1429, 14.0729, 18.1029, 21.0729, 24.9229, 28.1229, and so on. See the pattern?
By the way: The current suggested CENTER frequency With 16/1000 or 32/1000 on 20 meters is 14.1059.
(Why the …9 frequencies? Experts say that ending in a non-zero, odd number is easier to remember!)
Q: What’s a ‘CENTER’ Frequency? Is That Where I Set My Radio’s Dial?
For those new to waterfalls: the CENTER frequency is the CENTER of the cursor shown by common software. The cursor is what you use to set the transceiver’s frequency on the waterfall. If your software’s waterfall shows the frequency, then you simply place the cursor so that its center is right on the center frequency listed, above. If your software is set to show OFFSET, then you might, for example, set your radio’s dial frequency to 14.0714, and place the center of your waterfall cursor to 1500 (1500 Hz). That would translate to the 14.0729 CENTER frequency.
The FLDigi Manual of Operation is found here: http://www.w1hkj.com/FldigiHelp/
FLDigi can be downloaded here: https://sourceforge.net/projects/fldigi/
Join the Olivia movement:
1. Subscribe to the mailing list: https://Groups.io/g/Olivia
2. Join the Facebook group: https://www.facebook.com/groups/olivia.hf
For additional information on Olivia, check out:
http://blog.nw7us.us/post/168515010062/olivia-digital-mode-great-compromise
http://blog.nw7us.us/post/169114702522/are-you-an-amateur-ham-radio-operator-check-out
73 de NW7US
Update: More on Olivia, the Great Compromise Mode
Some HF digital modes were designed for long-distance (DX) radio-wave propagation via the ionosphere. One such keyboard-to-keyboard digital mode is Olivia.
Friday evening, 8 December 2017, at 0200 UTC {9-DEC}, Larry, N7ZDR, called an Olivia-mode 80-Meter digital roundtable net. The following video is a snapshot of about nine minutes of on-air net operations as received at my location in Omaha, Nebraska. My antenna is a wire run from an SEA marine autotuner mounted under the three-story-high roof’s eaves. I live in a high-RF environment within two miles of eight high-powered broadcast antenna facilities–TV, FM, AM–as well as business and public-service transmitters. All that RF desensitizes my receiver. The noise floor is also affected by industrial-level man-made RF noise.
No, Olivia is not lightening-fast keyboard-to-keyboard chatting, but it can get the job done. This following video shows some real-world operation in which the very weakest signals did not decode well. However, even with the 80-Meter band (center frequency is 3585 kHz) really difficult to work with, it did well in terms of what was available for the Ham Radio Deluxe DM780 software to decode.
Example QSO in Olivia Video:
[embedyt]https://www.youtube.com/watch?v=G7TlGEuStx4[/embedyt]
In 2005, SP9VRC, Pawel Jalocha, released to the world a mode that he developed starting in 2003 to overcome difficult radio signal propagation conditions on the shortwave (high-frequency, or HF) bands. By difficult, we are talking significant phase distortions and low signal-to-noise ratios (SNR) plus multipath propagation effects. The Olivia-modulated radio signals are decoded even when it is ten to fourteen dB below the noise floor. That means that Olivia is decoded when the amplitude of the noise is slightly over three times that of the digital signal!
Olivia decodes well under other conditions that are a complex mix of atmospheric noise, signal fading (QSB), interference (QRM), polar flutter caused by a radio signal traversing a polar path. Olivia is even capable when the signal is affected by auroral conditions (including the Sporadic-E Auroral Mode, where signals are refracted off of the highly-energized E-region in which the Aurora is active).
Currently, the only other digital modes that match or exceed Olivia in their sensitivity are some of the modes designed by Joe Taylor as implemented in the WSJT programs, including FT8, JT65A, and JT65-HF–each of which are certainly limited in usage and definitely not able to provide true conversation capabilities. Olivia is useful for emergency communications, unlike JT65A or the newly popular FT8. One other mode is better than Olivia for keyboard-to-keyboard comms under difficult conditions: MT63. Yet, Olivia is a good compromise that delivers a lot.
Join us — not just on the HF waterfall, but by joining our email-based group at:
or, on Facebook at:
–> https://www.facebook.com/groups/olivia.hf
Thanks for spreading the Olivia love! See you on the waterfall.
Addendum:
Current CENTER Frequencies With 8/250 (eight tones, 250-Hz bandwidth):
1.8269 MHz
3.5729 MHz
7.0729 MHz
10.1429 MHz
14.0729 MHz
18.1029 MHz
21.0729 MHz
24.9229 MHz
28.1229 MHz
See the pattern?
The current suggested CENTER frequency with 16/1000 or 32/1000 on 20 meters is 14.1059.
(Why the xxx…9 frequencies? Experts say that ending in a non-zero odd number is easier to remember!)
Q: What’s a ‘CENTER’ Frequency? Is That Where I Set My Radio’s Dial?
For those new to waterfalls: the CENTER frequency is the CENTER of the cursor shown by common software. The cursor is what you use to set the transceiver’s frequency on the waterfall. If your software’s waterfall shows the frequency, then you simply place the cursor so that its center is right on the center frequency listed, above. If your software is set to show OFFSET, then you might, for example, set your radio’s dial frequency to 14.0714, and place the center of your waterfall cursor to 1500 (1500 Hz). That would translate to the 14.0729 CENTER frequency.
The standard Olivia formats (shown as the number of tones/bandwidth in Hz) are 8/250, 8/500, 16/500, 8/1000, 16/1000, and 32/1000. Some even use 16/2000 for series emergency communication. The most commonly-used formats are 16/500, 8/500, and 8/250. However, the 32/1000 and 16/1000 configurations are popular in some areas of the world (Europe) and on certain bands.
These different choices in bandwidth and tone settings can cause some confusion and problems–so many formats and so many other digital modes can make it difficult to figure out which mode you are seeing and hearing. After getting used to the sound and look of Olivia in the waterfall, though, it becomes easier to identify the format when you encounter it. To aid in your detection of what mode is being used, there is a feature of many digital-mode software implementation suites: the RSID. The next video, below, is a demonstration on how to set the Reed-Solomon Identification (RSID) feature in Ham Radio Deluxe’s Digital Master 780 module (HRD DM780).
I encourage ALL operators, using any digital mode such as Olivia, to TURN ON the RSID feature as shown in this example. In Fldigi, the RSID is the TXID and RXID; make sure to Check (turn on) each, the TXID and RXID.
Please, make sure you are using the RSID (Reed Solomon Identification – RSID or TXID, RXID) option in your software. RSID transmits a short burst at the start of your transmission which identifies the mode you are using. When it does that, those amateur radio operators also using RSID while listening will be alerted by their software that you are transmitting in the specific mode (Olivia, hopefully), the settings (like 8/250), and where on the waterfall your transmission is located. This might be a popup window and/or text on the receive text panel. When the operator clicks on that, the software moves the waterfall cursor right on top of the signal and changes the mode in the software. This will help you make more contacts!
RSID Setting:
[embedyt]https://www.youtube.com/watch?v=lBIacwD9nNM[/embedyt]
+ NOTE 1: The MixW software doesn’t have RSID features. Request it!
+ NOTE 2: A problem exists in the current paid version of HRD’s DM780: the DM780 RSID popup box that lists the frequency, mode, and configuration with a link to click, does not work. HRD support is aware of the problem. You can still use the textual version that shows up in the DECODED TEXT window, a feature of RSID that you can select in the HRD DM780 program settings. This setting ensures that the detected RSID details appear in the receive text area. If you click the RSID link that comes across the text area, DM780 will tune to the reported signal, and change to the correct settings.
Voluntary Olivia Channelization
Since Olivia signals can be decoded even when received signals are extremely weak, (signal to noise ratio of -14db), signals strong enough to be decoded are sometimes below the noise floor and therefore impossible to search for manually. As a result, amateur radio operators have voluntarily decided upon channelization for this mode. This channelization allows even imperceptibly weak signals to be properly tuned for reception and decoding. By common convention amateur stations initiate contacts utilizing 8/250, 16/500, or 32/1000 configuration of the Olivia mode. After negotiating the initial exchange, sometimes one of the operators will suggest switching to other configurations to continue the conversation at more reliable settings, or faster when conditions allow. The following table lists the common center frequencies used in the amateur radio bands.
Olivia (CENTER) Frequencies (kHz) for Calling, Initiating QSOs
It is often best to get on standard calling frequencies with this mode because you can miss a lot of weak signals if you don’t. However, with Olivia activity on the rise AND all the other modes vying for space, a good deal of the time you can operate wherever you can find a clear spot–as close as you can to a standard calling frequency.
Note: some websites publish frequencies in this band, that are right on top of weak-signal JT65, JT9, and FT8 segments. DO NOT QRM weak-signal QSOs!
We (active Olivia community members) suggest 8/250 as the starting settings when calling CQ on the USB frequencies designated as ‘Calling Frequencies.’ A Calling Frequency is a center frequency on which you initially call, ‘CQ CQ CQ. . .’ and then, with the agreement of the answering operator, move to a new nearby frequency, changing the number of tones and bandwidth at your discretion. Even though 8/250 is slow, the CQ call is short. But, it is narrow, to allow room for other QSOs nearby. It is also one of the best possible Olivia configurations for weak-signal decoding.
– End of Addendum –
73
Come Join the Fun With Olivia on HF (Shortwave Digital Mode Olivia)
For those of you who have dived into the crowded but fun pool of FT8 operation or one of the other Joe Taylor modes (such as JT65 or JT9) and are excited now about digital modes, here’s something you might enjoy, too. Unlike those modes that allow you to make quick work of getting DX stations into your logbook, simply by exchanging callsigns, a signal report, and a grid square, there are other modes that offer keyboard-to-keyboard conversational QSO opportunities.
One such mode is known as Olivia and this mode offers keyboard-to-keyboard chatting for when you want to relax, and maybe make a friend. Ham radio is the oldest electronic social networking infrastructure.
In 2005, SP9VRC, Pawel Jalocha, released to the world a mode that he developed starting in 2003 to overcome difficult radio signal propagation conditions on the shortwave (high-frequency, or HF) bands. By difficult, we are talking significant phase distortions and low signal-to-noise ratios (SNR) plus multipath propagation effects. The Olivia-modulated radio signals are decoded even when it is ten to fourteen dB below the noise floor. That means that Olivia is decoded when the amplitude of the noise is slightly over three times that of the digital signal!
Olivia decodes well under other conditions that are a complex mix of atmospheric noise, signal fading (QSB), interference (QRM), polar flutter caused by a radio signal traversing a polar path. Olivia is even capable when the signal is affected by auroral conditions (including the Sporadic-E Auroral Mode, where signals are refracted off of the highly-energized E-region in which the Aurora is active).
Currently, the only other digital modes that match or exceed Olivia in their sensitivity are some of the modes designed by Joe Taylor as implemented in the WSJT programs, including FT8, JT65A, and JT65-HF–each of which are certainly limited in usage and definitely not able to provide true conversation capabilities. Olivia is useful for emergency communications, unlike JT65A or the newly popular FT8.
Here is a demonstration of a two-way transmission using the Olivia digital mode on shortwave. I am in QSO (conversation) with KA5TPJ. There are two other Olivia QSOs just below our frequency. Just above us is a lot of FT8 activity. Below the two other Olivia QSOs are PSK31 QSOs. The band is active. Olivia is not dead!
The standard Olivia formats (shown as the number of tones/bandwidth in Hz) are 8/250, 8/500, 16/500, 8/1000, 16/1000, and 32/1000. Some even use 16/2000 for series emergency communication. The most commonly-used formats are 16/500, 8/500, and 8/250. However, the 32/1000 and 16/1000 are popular in some areas of the world and on certain bands.
This can cause some confusion and problems with so many formats and so many other digital modes. After getting used to the sound and look of Olivia in the waterfall, though, it becomes easier to identify the format when you encounter it. To aid in your detection of what mode is being used, there is a feature of many digital-mode software implementation suites: the RSID. The video, below, is a demonstration on how to set the Reed-Solomon Identification (RSID) feature in Ham Radio Deluxe’s Digital Master 780 module (HRD DM780).
I encourage ALL operators in any digital mode such as Olivia, set the RSID feature on as shown in this example. In Fldigi, the RSID is the TXID and RXID (I believe).
Please make sure you are using the RSID (Reed Solomon Identification – RSID or TXID, RXID) option in your software. RSID transmits a short burst at the start of your transmission which identifies the mode you are using. When it does that, those amateur radio operators also using RSID while listening will be alerted by their software that you are transmitting in the specific mode (Olivia, hopefully), the settings (like 8/250), and where on the waterfall your transmission is located. This might be a popup window and/or text on the receive text panel. When the operator clicks on that, the software moves the waterfall cursor right on top of the signal and changes the mode in the software. This will help you make more contacts!
+ NOTE 1: MixW doesn’t have RSID features. Request it!
+ NOTE 2: A problem exists in the current paid version of HRD’s DM780: the DM780 RSID popup box to click does not work. HRD support is aware of the problem. You can still use the textual version that you can select in the settings so that it appears in the receive text areas. If you click the RSID link that comes across the text area, DM780 will tune to the reported signal, and change to the correct settings.
+ NOTE 3: some websites publish frequencies that are right on top of weak-signal FT8, JT65 and JT9 segments. Even if that is a matter of contention, follow the regulations and be kind: DO NOT QRM weak-signal QSOs! AGAIN: make sure that your signal does not cross into other sub-bands where weak-signal modes are active. For instance, do not have any part of your signal at x.074 or higher, as this is the sub-band for FT8, JT65A, and JT9.
Quick Reference: we in the active Olivia group suggest 8/250 as the starting settings when calling CQ on the USB dial frequency of 14.072 MHz with an offset of 700 Hz, on 20m–that translates to a CENTER frequency of 14.0729 MHz. On 40m, 7.072 MHz on the dial with an offset of 700 Hz (and again 8/250) which translates to a center frequency of 7.0729 MHz.
Also, do not quickly switch to other modes without calling CQ for at least a five-minute window. It is really horrid when people call CQ and change settings, modes, bandwidths, tones, every time they call CQ during the same session!
There are several key resources that we in the Olivia community are developing, to make it easier for you to enter into the great world of Olivia. One is an active support e-mail group to which you can subscribe at https://groups.io/g/Olivia — a group containing topical areas of interest which can be filtered so that you are not flooded by email containing topics of which you are not interested. It has a files section, as well, in which we will add helpful how-to instructions and so on.
Another resource is our Facebook group, at https://www.Facebook.com/groups/olivia.hf — also with a files area containing help files. This group is a great resource for getting help from like-minded Olivia digital mode enthusiasts.
Some more eavesdropping on an Olivia QSO:
And, two more:
One last note: Olivia is NOT a weak-signal mode. There are no points won by barely making a contact. In the USA FCC regulations, you are directed to use only the power necessary to make the QSO. Typically, with poor propagation, using Olivia with an output power of 100w is the minimum to establish a reliable circuit. You just cannot go beyond your rig’s duty cycle (don’t burn out the finals in your radio!). You also must be sure that you do not overdrive the audio chain into your radio. Be sure that you do not have RF coming back into your audio chain. Yes, 100 watts is acceptable. Don’t let anyone convince you otherwise. After all, think about RTTY.
Welcome to Olivia! See you on the waterfall.
73 de NW7US
CALLING ALL RADIO AMATEURS – THIS IS W1AW IN NEWINGTON, CT
I would suspect that if you have done even a bit of tuning around the HF dial in the last few months, you have probably heard W1AW/0-9 making contacts. This week W1AW, the ARRL mothership in Newington, CT, has been on the air as W100AW in celebration of the ARRL anniversary.
As busy as that sounds, W1AW is consistently on the air with a great variety of activities. Yesterday I took the opportunity to copy their digital modes broadcast. http://www.arrl.org/digital-transmissions
ARRL has various means of promulgating a great deal of information. The primary way I usually receive a good portion of it is via email. I thought it would be interesting if I could try and copy their digital transmission of their bulletin, which I was able to do yesterday.
Every weekday, W1AW sends out a bulletin twice a day on multiple bands while rotating through three different digital modes: Baudot (RTTY), PSK31, MFSK16. The first broadcast kicked off at 5pm (local) which I was able to copy of 17M (18.105 MHz). It appears to be ARRL’s propagation bulletin. Here is what I copied:
Please find my full copy here.
Later in the evening (8pm local), I copied the next broadcast which looks like their DX bulletin:
…. and the complete text is here.
During the 8pm transmission, I was able to copy the bulletin on 10M, 15M, 17M, and 20M. I could not find it on 40M or 80M.
Although these bulletins are easily obtainable via email or from ARRL’s website, I enjoyed copying the broadcast from here in eastern Kansas.
China heard on JT-65? Call 3T4CAV?
Did I really hear China on 40M JT-65? |
Last night I played around some more with JT-65. The band conditions did not appear to be as good as they were the other night. I was on both 20m and 40m.
I worked a few stateside stations in the 40 minutes I played on the bands.
When I looked at PSK Reporter this morning I was greatly surprised to see one of the stations that I had spotted. It must have been one of the very first decodes I had after firing the rig up.
3T4CAV – in CHINA! I can’t find this call sign on any of the online databases, so I don’t know if this is a mistake in the database, I guess I doubt it is, but this is pretty amazing. And the signal report was -5db – which is actually a pretty strong signal report on JT-65.
I don’t remember seeing the decode on my screen, but I could have missed it as I was getting everything configured.
Anyway, that is pretty amazing if true.
Judging by the location of spots (both sent and received) around the country and down to South America, my 66′ ladder fed dipole in the attic seems to be working pretty well for this mode.
I do see lots of stateside stations working DX that I am unable to decode, so I think my initial feeling that receive is weak could still be true. But its not stopping me from having fun on this mode!
First JT-65A Contacts!
JT-65 Spots on 40 Meter with 2 Watts |
Over the weekend I setup WSJT-X on my old XP computer. I let it do some decoding off and on over the weekend on several bands – and I was decoding well!