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!
Een interresante brief van VolkerWessels Telecom vandaag: ze willen in opdracht van KPN een nieuwe "SAD-kast" plaatsen en daarvoor moet een kabel door onze grond. Het lijkt er dus op dat:
+ hele hoge VDSL snelheden mogelijk worden
- glasvezel en meer upstream snelheid er dus voorlopig niet in zit
Ik ben benieuwd. We gaan nog even contact opnemen, de voorgestelde plek voor de kast is niet ideaal, hij gaat enigzins in de weg staan voor fietsen die achterom rijden.
Somebody at 220.127.116.11 was trying at a very high speed to brute-force /wp-login.php for one site on my server. The downside was that there was no /wp-login.php or any part of wordpress to brute-force, but that did not seem to deter the attacker. A temporary firewall rule now rejects all attempts. Update 2014-07-31: Next load of attempts from 18.104.22.168. And looking back in the logs shows other similar attempts.
This evening I tried another pass of the SO-50 amateur radio satellite. It wasn't as high as the afternoon pass, only 66⁰ maximum elevation. The experiences from the afternoon pass learned me to search around a bit for the downlink signal. I did not hear a lot of activity, it almost sounded to me like the transponder wasn't "armed" with the 74.4 Hz ctcss tone. This tone activates the transponder for 10 minutes, but to actually use the transponder you need to use a 67.0 Hz ctcss tone. Switching tones on the fly isn't easy when the FT-857 is controlled by gpredict, so I'll either have to control that via the computer assisted tuning (CAT) interface and rigctld or temporary switch to manual and use the memory in the FT-857 which has the different ctcss tone. Browsing the rigtctl(1) manpage suggests a script which can set ctcss tones is quite doable. Update: Indeed, it can be done. Hamlib can't read the current ctcss tone, but it can set it on this radio. Model 2 in rigctl is the connection to a running rigctld on localhost.koos@machiavelli:~$ rigctl -m 2 -h Usage: rigctl [OPTION]... [COMMAND]... Send COMMANDs to a connected radio transceiver or receiver. .. Commands (some may not be available for this rig): .. C: set_ctcss_tone (CTCSS Tone) c: get_ctcss_tone () D: set_dcs_code (DCS Code) d: get_dcs_code () ?: set_ctcss_sql (CTCSS Sql) ?: get_ctcss_sql () ?: set_dcs_sql (DCS Sql) ?: get_dcs_sql ()and it works:koos@machiavelli:~$ rigctl -m 2 C 744 koos@machiavelli:~$ rigctl -m 2 C 670 koos@machiavelli:~$And the ctcss frequency on the radio indeed changes with what I set. And I can do this while gpredict is tuning the radio.
: New radio for me: a secondhand Yaesu FT-857, selected with satellite work and expansion to HF in mind. In the first tries with listening to SO-50 I learned:
- Use a headphone, so I soldered a cable to connect a stereo headphone to the mono headphone output on the radio
- The SO-50 output frequency has shifted, so when I let gpredict control the radio I had to tune around a bit to find the signal. An enormous plus for gpredict here is that it will accept the change in frequency and will continue working and applying doppler shift from there.
The picture is from the first attempt, sitting in the backyard with everything ready and enjoying myself. Radio, antenna, laptop with gpredict. The radio is powered by a PC power supply at the moment, but I also have batteries.
I soldered the cable for a stereo headphone on the mono phone output on the FT-857 this morning and went to listen for the SO-50 pass with tuning done by gpredict. And I missed half of the satellite pass because gpredict has the 'preprogrammed' frequency and the satellite downlink frequency seems to be drifting away from this frequency, far enough to fall out of the FM receiver passband. I kept hearing nothing so I switched back to manual frequency control with the doppler-shifted frequencies preprogrammed in the radio and I found it again, somewhat shifted. I switched back to letting gpredict control the frequency but used the tuning dial on the radio to find the right spot, after which gpredict kept track of what I did. I still find this an awesome feature in gpredict, the two-way tracking of frequencies. It was as busy as could be expected on an FM satellite on a Sunday afternoon pass with nice weather, so I could not find a 'hole' in which to call CQ or answer some call I heard. The headphones do help with hearing the audio from the radio, so a good thing I made that cable.
I also managed to get CHIRP working with the Yaesu FT-857 radio. I had to RTFM: CHIRP does not use the normal CAT commands, it uses the clone mode of the radio.
First thing to try with the new Yaesu FT-857 amateur radio: get it working with gpredict for amateur satellites. What gpredict can do is control the radio via rigctld, part of Hamlib to set downlink (receive) and uplink (transmit) frequencies automatically to the doppler-shift correct frequency. I bought a CT-62 USB cable for this which is the cable for the Computer Aided Tuning (CAT) interface on this range of radios with a FTDI based serial interface on the side of the computer. I added a new radio in gpredict with:
So I installed libhamlib-utils and tried to get rigctld working. At first it gave errors on communicating:
- Radio type: FT817/857/897 (auto)
- PTT status: Read PTT
- VFO Up/Down: Not applicable$ rigctld -m 122 -r /dev/ttyUSB0 -v -v Opened rig model 122, 'FT-857' ft857: error reading ack ft857: error reading ackAnd I found out the default baudrate of rigctld is 38400 bps and the FT-857 was set to 4800 bps. I tested first with 4800 bps and later changed the rate on the radio to 38400 bps and tested again. Now running:$ rigctld -m 122 -r /dev/ttyUSB0 --set-conf=serial_speed=38400 -v -v Opened rig model 122, 'FT-857'The radio needs to be in 'split' mode so VFOa and VFOb can be set sepately and receiving is on the VFOa frequency and transmitting on VFOb. The good part, especially for SSB satellite work is that gpredict will follow frequency adjustments on the transciever and will track from the adjusted frequency. With the 'lock' function enabled (L button) this will also make the uplink frequency follow downlink changes. Change the (receiving) frequency on the transciever and the transmitting frequency will be updated accordingly. This should make SSB satellite work with one simplex transciever easier. Sofar in tests without actual satellite communication things seem to work. Next is a test with SO-50 in FM mode, probably on the high pass I see coming Sunday afternoon. A test with an SSB satellite (first trying to receive) will probably be possible later this week with the Funcube-1 (AO-73). I found a
gpredict trsp file for FUNCUBE from G0HWWwhich has a low and a high swapped and confuses gpredict. The one at Funcube AO-73 transponder file for gpredict has this correct.[FUNCUBE BPSK Telem] DOWN_LOW=145935000 [FUNCUBE U/V] UP_LOW=435130000 UP_HIGH=435150000 DOWN_LOW=145950000 DOWN_HIGH=145970000 INVERT=true
For a while I have been considering my wishes for a more elaborate amateur radio. What I want to do with it is continue and expand the use of amateur satellites, and try to get into PSK31 on HF, starting on the 20m band. So a list of must haves and should haves arose: all-mode, portable, computer assisted tuning, HF support, 2 meter and 70 centimeter and an increas of power from 5W. Adding it all up and looking for a reasonable price I ended up considering the Yaesu FT-857(D). It's in the middle between the FT-817 (too low power, still 5 watts) and the FT-897 (too heavy: 3.9 kilograms). And a reasonable pricetag, were other amateur radio brands have nothing comparable or at a much higher pricetag. I went looking for a second-hand one and when we got back from holiday a nice one (FT-857 with DSP and installed filter, and a remote control+DTMF hand microphone) showed up from Communicatie Centrum Venhorst - Hilversum and I bought it. Picked it up this week, and I am learning using it. I listened to SO-50 this evening using this radio with a lot of wires on the table in the backyard.
A clear sign this week I am not a system administrator anymore: I had no easy answer to "where can we find some Torx screwdrivers to open the dishwasher". Using contacts that were from when I was a system administrator helped find the right screwdrivers and the dishwasher was opened and repaired.