Tuesday evening I was at the Veron region A08 club meeting and I watched as someone else played with the radio for a while. We noticed some interesting activity on the HF bands: people making DX contacts from as far as Costa Rica mixed with people clearly having a very local contact. People working distant stations (DX) usually just want to exchange callsigns and a signal report and maybe some niceties and get on to the next contact, people having a very local contact can chat on for a while talking about the weather, their car, the upcoming visit to the dentist and other items, usually called 'ragchew'. It's very funny to hear the different styles mixed.
: Did anybody record this contact? I missed it because of work and it seems it was a bit hard to receive this contact in the Netherlands (telebridge was via Italy) so a few fellow amateurs who I tried to get interested in space communications were a bit disappointed.
I created the simplest possible antenna for use in the 10 meter HF bands: a dipole from recycled utp wire using some turns of coax as 'ugly balun'. I used this Wire antenna calculator to calculate the needed lengths. The choice for the 10 meter band was for a purely practical reason: this is the length I can put up under our roof easily. So I am trying PSK31 on the 10 meter band, around 28.120 MHz. The first results the past evenings was a constant S6/S7 noise level, which leaves little space for other signals. And absolutely no response to my CQ calls. But conditions can change, and this evening I am hearing some PSK31 traffic, and IZ3ZOW managed to copy my callsign in Italy but we couldn't make it a whole QSO. I also tried various setting for the noise reduction in the FT-857 radio to see whether that has a positive or negative influence on PSK31. I am seeing other traffic, so the 10 meter band must be opening a bit. I spotted OM0AST calling CQ from the Slovak Republic but he could not hear my signals. Update: For me that opening didn't last longer than about 20 minutes.
: Bob Witte K0NR compares the Yaesu FT-817 with the Elecraft KX3 specifically for portable/SOTA operations. An interesting article, there is more to compare than just the price.
In a few documents about the FM transponder on the SO-50 I noticed the use of the term PL tone where I expected the term CTCSS, for example in Operating SO-50 by Howard Long, G6LVB. I started wondering about the origins of PL tone and read the explanation on Continuous Tone-Coded Squelch System - en.wikipedia.org:CTCSS is often called PL tone (for Private Line, a trademark of Motorola) In amateur radio, the terms PL tone, PL and simply tone are still used somewhat commonly.I'll keep calling it CTCSS.
: I haven't seen this mentioned in this group before, so I thought I'd mention it once: the fundraiser to help Amsat launch the Fox-1C satellite which will include an FM transponder.
An interesting new message showing for the wireless config:[2668364.843138] cfg80211: Calling CRDA to update world regulatory domain [2668365.630995] cfg80211: World regulatory domain updated: [2668365.631018] cfg80211: DFS Master region: unset [2668365.631029] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) [2668365.631046] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (N/A, 2000 mBm) [2668365.631062] cfg80211: (2457000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm) [2668365.631078] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (N/A, 2000 mBm) [2668365.631093] cfg80211: (5170000 KHz - 5250000 KHz @ 80000 KHz), (N/A, 2000 mBm) [2668365.631109] cfg80211: (5735000 KHz - 5835000 KHz @ 80000 KHz), (N/A, 2000 mBm) [2668365.631124] cfg80211: (57240000 KHz - 63720000 KHz @ 2160000 KHz), (N/A, 0 mBm) [2668365.632073] cfg80211: Calling CRDA for country: NL [2668365.661681] cfg80211: Regulatory domain changed to country: NL [2668365.661703] cfg80211: DFS Master region: unset [2668365.661715] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) [2668365.661731] cfg80211: (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm) [2668365.661747] cfg80211: (5170000 KHz - 5330000 KHz @ 80000 KHz), (N/A, 2000 mBm) [2668365.661763] cfg80211: (5490000 KHz - 5710000 KHz @ 80000 KHz), (N/A, 2700 mBm) [2668365.661778] cfg80211: (57240000 KHz - 65880000 KHz @ 2160000 KHz), (N/A, 4000 mBm)The message about DFS Master region is new to me, compared to the crda messages I saw last february.
: I built my own digital radio interface for my new Yaesu FT-857 radio with audio transformers for separating the radio and the PC and a cheap usb sound interface. On the plus side: I can use this interface dedicated for fldigi, no system sounds will be played over it and it was only 9 euro.
Tests look good, this will also allow me to record the incoming audio on satellite QSOs. Now to find someone nearby willing to do PSK31 on 2m or 70cm, or bring radio, interface and laptop to an HF antenna.
Some more work on the digimode interface for the FT-857 radio: setting it up on a real circuit board, to be built into a plastic casing. This time I heard a strange ticking sound when recording audio from PI3UTR but again it seems this clicking sound is a local problem normally filtered out from the audio path of the radio. When I picked up PI3UTR on the Wouxun KG-UVD1P radio I heard the same ticking noise. New respect for the audio filtering in the FT-857, but things like this make me question the digimode interface every time I'm testing it.
Friday evening I had time to work on the 'digimode' interface for the FT-857 radio. I set up a breadboard with the audio transformers and started making cables from the transformers to the USB audio interface. Then I added the cable to the radio on the other side. All of the earlier mentioned interfaces had resistors to regulate the signal level so I started with 12K resistors between the radio and the transformer in the radio to computer audio path. This gave me a weak signal when recording the result with audacity on the computer so I switched to a 6k8 resistor which improved audio but it still wasn't great. So the resistor was replaced by a simple wire which gave me good audio when recording from the PA00NEWS transmission on the PI3UTR repeater. I did notice some low hum while recording, but I realized that was just the CTCSS tone on the repeater output. Normally this tone is filtered out when hearing the audio through the speaker of a radio.
I listened to a satellite pass today of the AO-7 satellite. This is the first time I tried listening to a single side band (SSB) satellite transponder. This adds a whole new set of problems to 'trying to hear callsigns and other information in the noise' : the very nature of single side band (there is no carrier for the receiver to lock to, it just works from the frequency the operator sets) combined with doppler shift makes it hard for me to hear anything. And there is a 100 kHz wide passband on the transponder in which multiple QSOs can be active in different fitting modes. I did hear some morse (which I can't decode) and something which sounded like a conversation but I could not make out callsigns or anything. Better luck next time, I will keep trying!
The cable and parts for a 'digimode' interface for the new FT-857 radio are on their way. Such an interface will allow me to get audio from the radio directly into a computer and audio from the computer directly into the radio. This will allow digital radio modes such as PSK31, RTTY or AFSK. These modes allow bits (text, or databits) to be exchanged over radio. The simplest interface like FT-817 AFSK cable couples these directly but based on the advice of fellow radio amateurs I will use audio transformers to decouple the computer and radio and keep stray radio signals out of my computer and any interference from the computer out of my radio and I decided to use a cheap USB audio interface. What I will build is based on Digital VOX sound card interface but without the 'VOX' part and iPhone / Baofeng interface (schema) and El Cheapo AFSK (e.g. RTTY) USB interface (for FT-8×7) - remco.org. Update: Parts have arrived, time to build something on a development board first.
Good catch this morning on a southwest - northeast pass of SO-50: I managed to have a QSO with R1AO who operates from St. Petersburg in Russia! A distance of 1778 kilometers. This was the first QSO on satellite with the new FT-857 radio. Update: Thanks to eQSL.cc I already have the QSO confirmed.
: Ook in het spoorwegmuseum staat de Fyra uitgerangeerd.
Oh I can agree so much with Some idiot’s been using my e-mail address for years - ars technica. Almost all of my previous rants about the subject of other people thinking they have my address or think it's a nice spamdump were about the xs4all address I have since about a week before the official start of xs4all in 1993. But I also get the same with the gmail address I have. The usual is about someone who thinks it's the address of a relative. For example when I browse it now: about someone in the hospital, a mother explaining how to fix things with bank access from abroad (response to a scam attempt?), a forwarded mobile phone cancellation, information for a child going to study in Toronto. Or a discussion about company plans to
professionalise their e-mail campaignsspam. I have also received several e-mails for a vicar.
And a non-catch: I tried receiving the AO-73 Funcube-1 amateur satellite but no go. I thought it would be in eclipse mode after 23:00 localtime which would mean the inverting transponder would be available. I noticed gpredict was reacting weird to the AO-73 Funcube-1 transponder file I found earlier so I checked again and found a better source, installed it 3 minutes before the pass.
New catch: I heard the UO-11 amateur satellite this evening. It transmits telemetry as an AFSK signal (bits as audio within an FM signal, more info at Frequency-shift keying - Wikipedia English), although very weak. When I have a working audio interface on the FT-857 I'll try to record some telemetry signals and decode the data.
Another SO-50 amateur satellite pass early this afternoon so I had the FT-857 radio set up with the laptop. I added two ferrite cores to the CAT cable and locked them in place with tie-wraps. The cable kept working even when I transmitted a few times during the pass. Getting the radio tuned to the satellite downlink once and then having the software doing the rest of the doppler correction is quite nice. But, no luck in making a QSO on the satellite. I heard at least M0SAT loud and clear and responded to his CQ but no contact.
Yesterday evening I tried to make some contacts during an SO-50 amateur satellite pass and twice the CT-62 USB interface to the radio crashed, with messages like:Aug 1 20:33:15 machiavelli kernel: [48075.216289] hub 6-0:1.0: port 2 disabled by hub (EMI?), re-enabling... Aug 1 20:34:45 machiavelli kernel: [48165.984146] hub 6-0:1.0: port 2 disabled by hub (EMI?), re-enabling...I had to unplug and replug the cable every time to get /dev/ttyUSB0 available to rigctld again. A few hours later the proverbial light above my head went on: EMI means electromagnetic interference, maybe transmitting quite close to the laptop is the problem. So this evening I created the same setup and tried transmitting so I could attack the problem and see if some ferrite cores would help. The problem decided to not return, even with the CAT cable and the antenna cable laying parallel. I'm still going to use at least one ferrite core to try to keep the USB interface from crashing.
I brought the Wouxun KG-UVD1P radio today on my bicycle and listened to the PI3UTR repeater on both parts of the cycling commute. In the afternoon I heard KM6DU active via echolink on the repeater and answered his call, giving a nice QSO. It was 99% Internet and 1% amateur radio, but it was nice to be able to do this thanks to echolink. KM6DU reported my sound was a interrupted a lot, so I stopped my bicycle and raised my radio from belt level (about 1 meter above the ground on my recumbent bicycle) to holding it up (somewhat more than 2 meters above ground) which changed the signal from lots of interruptions to clearly understandable. It's amazing what a bit of antenna height can do!