Digital Modes

After some time playing with SDR I decided to finally get a decent dedicated shortwave radio.

In this image the Sangean ATS-909X2 is set to receive at 14.074 MHz in USB mode to capture some FT8 signals.

The phone is running the FT8CN app and it captures the audio to decode the messages via the microphone.

7.074 MHz and 28.074 MHz also work great for this.

I followed the instructions on the WPSD page for setting up my hotspot and radio. I registered with regist.dstargateway.org. I have the hotspot set up as a repeater on my Kenwood TH-D74. The echo, info, adn link commands work, and I can hear traffic from the reflector when connected. But when I try to make a contact (CQCQCQ in the UR field) it doesn't seem to go through.

In fact, about 30 seconds after each CQ attempt, I'll get a message from the hotspot saying connected to reflector even though it should already be connected.

(Crossposted on !dabradio)

I have these receivers:

1. TechniSat TechniRadio1 (shitty amp/speaker quality)
2. Envivo Retro (shitty amp/speaker quality; antenna: 66cm)
3. Envivo PO-1585 (good amp/speaker quality; antenna: 90cm)

I won’t talk about receiver ① because it behaves the same as receiver ②. ② & ③ are the same brand but they behave differently. Envivo is perhaps just an Aldi rebranding from different makers.

② finds 101 signals but only “BBC WS” (World Service) from the BBC. Most importantly, it can tune BBC WS at any time.

③ finds 57 or 72 signals (probably depending on weather at the time of the scan). It always finds these BBC stations:

• BBC WS
• BBCAsian
• BBC R6M (radio 6 Music)
• BBC R5L (radio 5 Live)
• BBC R4Ex (radio 4 Extra)
• BBC R3
• BBC R2
• BBC R1
• BBC R1x (radio 1 Xtra)

③ cannot tune any of the BBC stations. It only finds them. Exceptionally, a couple floors above ground it tuned BBC WS, once. Apart from that one time, it either says “connecting…” indefinitately, or “service not available”.

WTF is going on here? It might be normal for one receiver to have a better tuner than another, but in this case one finds many more BBC stations but tunes none of them. We might speculate that the scanning algorithm of the radio that finds more stations just has a lower signal/quality threshold for what it accepts, but the one finding more BBC finds fewer stations overall.

It’s a shame that despite the invasion of the Internet of Shit (IoT), radio makers have not realised it would be greatly useful to be able to attach a radio to the LAN to access tuning info from a PC.

On Thursday, January 18th, I discovered that the Winlink APRSLink callsign is now WLNK rather than WLNK-1.

Here's how ...

My APRSLink login attempt through WLNK-1 (over VHF) failed so I switched to APRSDroid (over TCP/IP) to rule out an iGate/digi issue.

When I started APRSDroid I received a "message waiting" notice from WLNK instead of the expected WLNK-1.

So I sent my APRS messages to WLNK and was able to login over both VHF and TCP/IP.

This callsign change has not been mentioned at https://winlink.org/APRSLink

My radio club does a weekly digital net and plays with different modes, and tonight is JS8CALL night. Getting on around 9:00 PM EDT

Hopefully I set up my radio correctly 😅

I just realized tonight that I could check into the PAPA Tech net on 4 different radios in 4 different digital modes. :)

Had the pleasure of operating some FT8 this afternoon on 15m. Made 2 contacts with Japan, running 10 watts from the Discovery TX-500 into a WRC Platinum 1000.

Most of my limited experience is testing setups with WSPR, but I'd like to try something more like ragchewing with 5W, so I've been looking at Olivia. I've managed to decode an Oliva tx from someone 1500 km away, but have had no luck with anyone hearing me. (I get spots on WSPR, so I know my computer output and antenna are working on some level.) Olivia doesn't seem to be too active, though. Anyone want to try to communicate?

I'm in the Chicago area, so ideally looking for someone in North America but not in the Midwest (to stay out of the skip zone). Depending on weather and band conditions, I'd be looking for something in the evening (roughly 0200 UTC, but flexible), this weekend or over the next week.

Edit: I'm also up for trying other keyboard-to-keyboard modes if people like others that are tolerant of weak signals.

Got GD77 onto my MD-UV390. Installation was dead simple. Now building the codeplug. The codeplugs are different from the TYT CPS and the GD77 CPS.

Good morning, all:

I'm looking for users of the Icom IC-7200 HF transceiver who have had success using Winlink with either the ARDOP or VARA HF modems. I've been completely unable to get the ARDOP modem to actually connect, even to local gateways via ground wave, and while I have gotten VARA working, it's super slow.

As an aside, FLDIGI digital modes ALSO don't work great, including PSK31 and MT63. However, WSJT-X works fabulously.

I suspected it was an issue with audio input volume over USB, so I sent an email to Icom America about whether or not it was possible to get service but haven't heard back yet. Mainly because I just sent the email this morning. :-)

If you are successfully using your IC-7200 on ARDOP, VARA HF, or PSK31, I'd love to hear how you did it, with my thanks!

Recently started looking at this radio. After Delta paid me to postpone my trip for a day, they gave me enough for this radio and then some. I stopped by HRO and bought it. I spent some time today tuning an EFHW made from a chalk line, and hopefully tomorrow I will get out to use it. Anyone used one of these before for digital, or other modes? Any M17 HF nets?

The APRS SMSGTE service was supposed to have gone down a month or two ago, but it has been working for me the entire time, at least when I message myself or my wife. I've chatted with others on others forums and other people have said it's not working for them.

Just curious, is it working for anyone else?

After the post in here about W0CHP dashboard for Pi-Star I decided to dedicate a hotspot to M17. I have it functioning, but that means now I need a radio. :) who doesn't want a good excuse to buy a radio?

It took me a while to understand the principle of operation and the tools to use and their interactions. So I've posted some explanation about it.

Recently updated my pi-star with this version and WOW is it a lot more responsive and easy to use. Even has a few different digital modes to play around with, like M17.

This is my very highly modified and customized fork of MW0MWZ’s Pi-Star software, and I call it “W0CHP-PiStar-Dash” (abbreviated as WPSD). There are so many large changes, divergences and new features, it merited my own fork/version.

There are a number of changes that could be made to the FT8 protocol to make it faster and more resilient to low signal strength. Some of these changes include:

1. Increase the bandwidth: Increasing the bandwidth would allow more data to be transmitted per symbol, which would improve the speed of the protocol. However, this would also make the protocol more susceptible to interference.

2. Use a different error correction scheme: The current error correction scheme in FT8 is relatively simple, and it can be difficult to correct errors when the signal is weak. Using a more sophisticated error correction scheme would improve the resilience of the protocol to low signal strength.

3. Change the modulation scheme: The current modulation scheme in FT8 is based on frequency shift keying (FSK). Changing the modulation scheme to something like quadrature amplitude modulation (QAM) would improve the spectral efficiency of the protocol, which would allow more data to be transmitted over a given bandwidth.

4. Use a different symbol rate: The current symbol rate in FT8 is 31.25 baud. Using a lower symbol rate would improve the resilience of the protocol to low signal strength, but it would also reduce the speed of the protocol. These are just a few of the changes that could be made to the FT8 protocol to make it faster and more resilient to low signal strength. The best changes to make would depend on the specific requirements of the application.

In addition to the changes mentioned above, there are a number of other things that could be done to improve the performance of FT8 in low-signal conditions. These include:

1. Using a better antenna: A better antenna will improve the reception of weak signals.

2. Using a higher output power: A higher output power will increase the strength of the transmitted signal, which will make it more likely to be received by the other station.

3. Using a noise-cancelling filter: A noise-cancelling filter can help to reduce the noise in the received signal, which will make it easier to decode the signal.

By making these changes, it is possible to improve the performance of FT8 in low-signal conditions and make it possible to communicate over longer distances even with weak signals.

This looks fun, I might give it a go.

I found this software when trying to get into M17. There are other versions like DudeStar but this one worked best on my system (Debian Linux). Anyone used M17 Yet?

I use mine as an I-Gate with the default firmware installed on it. Has anyone looked into building open source firmware for these? The reason I ask, it seems as the device does not really transmit any packets. This could be a setting or a filter I have wrong. so maybe someone has some insight.

I saw this on the Mastodon.Radio feed, now I want one.

I live in a valley so it’s hard to hit any local digital repeaters. Built this to hit all the modes I can. Full duplex.

It wasn't the longest contact ever but I did manage Washington state from San Diego last weekend. running 2 watts into a WRC antenna from the QRP-Labs QDX.