FT4 curve increasing
Ham Radio
Lots of FT4 activity on 20 and 40 meters from this part of the country (Ottawa) since the COVID19 crisis.
Lots of DX on 20 as well if you don’t mind using FT4. Checking 15 meters every day and nothing heard. Lots of FT8 on 80 meters but little activity on FT4 ... strange. Be safe! 73, Bernie, VE3FWF
|
||||
|
||||
The Resurrection Day Olivia Digital Net - two more times, today.
#Olivia
The Olivia Resurrection Day NET, on 14.107 dial, center 14.1085, 16/1000 - went well at the 1530 UTC net time. We had four additional stations, that checked in:
K3UK, KC4LZN, N1TYH, and, N7ZDR This net will be called two more times, today.
Here are the proposed times: + 1930 UTC on 14.107 dial, center 14.1085, 16/1000
+ 2130 UTC on 14.107 dial, center 14.1085, 16/1000
Remember that we have a Facebook group:
Also, remember to subscribe to our email list, if you have not yet done so.
+ https://QRZ.com/db/NW7US
|
||||
|
||||
Re: WIN 10 Standby mode , stopping programs running
Graham
Hybrid sleep .......
W10 standby is not a simple standby after a certain time - it's hybrid sleep (see Google) by default on a desktop, laptops different. That time is user selectable. If you just want to power off the screen for a while before sending it to sleep for example then it's Settings>Power & Sleep You can also get into the detail under the Additional Settings link on that page. Alan G0TLK
|
||||
|
||||
Re: Mystery JT65 signal
Patrick Lindecker
Hello Andy,
If KVASD (soft decoder) is ON, extract it to OFF. This decoder is very sensitive but introduce false decodes. The standard “hard decoder” has not this problem (although a false decode is still possible but very rare).
73 Patrick
De : main@digitalradio.groups.io [mailto:main@digitalradio.groups.io] De la part de Andrew OBrien
Hi everyone,
|
||||
|
||||
Re: Mystery JT65 signal
Graham
Any of the compressed format systems , will 'always produce ''valid'' out put , when subjected to a repeating ''noise''
pattern , where pre formatted messages are encountered, it becomes ever more ' realistic' Much merriment , is had, when opera responds to a repeating , 'noise pattern [ usually a keying attribute of a 'beacon kit' excited transmitter' ] and go's on to print , what is perceived as false detections , only applies to 136 band , where s/n levels to -45 dB are encountered , hence very low spurious signals , cause 'havoc' , once lodged in the call list , then other stations , similar respond ... catch22 I suspect, this is a repeating beacon , but not JT system , intruder more like ? 73-Graham g0nbd
|
||||
|
||||
Mystery JT65 signal
Andrew OBrien
Hi everyone,
|
||||
|
||||
WIN 10 Standby mode , stopping programs running
Graham
WIN 10 Standby mode , stopping programs running
Previously, this was not a issue , win-xp and 7 , the upgrade to win-10, apperese to of embodied a pre-set list of parameters ie, access to microphone, eliminated the ic7100 rx data feed Q-Is there a setting, to prevent a program , ie, data mode , stopping, when the pc enters , 'standby mode, ? Previously, the video to the vdu , may of stopped, but, the program[s] continued running , attribute setting may be ? Tnx- Graham g0nbd
|
||||
|
||||
Graham
k3SIW ,spotted by NK9M Assume on the LowFER band , level showing ~ -43 dB, 50 down from the previous , 1 watt reduced to 10 uWatts ? all correlation ,spot, but, time looks good = good spots 73-Graham 2020-04-09 02:58:46 K3SIW AA NK9M EN51UQ 0 136 -43 Op32__~43dB2020-04-09 01:58:46 K3SIW AA NK9M EN51UQ 0 136 -43 Op32__~43dB2020-04-09 00:58:46 K3SIW AA NK9M EN51UQ 0 136 -43 Op32__~43dB2020-04-08 23:58:46 K3SIW AA NK9M EN51UQ 0 136 -44 Op32__~44dB2020-04-08 22:58:46 K3SIW AA NK9M EN51UQ 0 136 -44 Op32__~44dB2020-04-08 21:59:05 K3SIW AA NK9M EN51UQ 0 136 -43 Op32__~43dB
|
||||
|
||||
New release of MULTIPSK (4.43) - P25 Phase 1
#Multipsk
Patrick Lindecker
New release of MULTIPSK (4.43) and Clock (1.11.9)
Pour les francophones: la version en français de ce message se trouve sur mon site (http://f6cte.free.fr). Il suffit de cliquer sur le lien "Principales modifications (courriel avertissant de la sortie de la nouvelle version)".
The new release of MultiPSK (4.43) is on my Web site (http://f6cte.free.fr/index_anglais.htm). The MD5 signature of the downloaded MULTIPSK_setup.exe file to, possibly, check (with WinMD5 for example), that the downloading works without error, is equal to: 91a82da992983d78672aea610fb9d055 Multipsk associated to Clock are freeware programs but with functions submitted to a licence (by user key).
The main improvement of MULTIPSK 4.43 is the following:
Ham P25 Phase 1 decoding (but not the voice)
"P25" is the acronym for "APCO Project 25", for two different radio systems: "Phase 1" (used also by Hams) and the most recent "Phase 2" (not used by Hams). Only the "Phase 1" P25 mode is decoded by Multipsk. It is used in VHF and in UHF. It is a mode for professionals but also used by amateurs (according to a precise organization). For Hams, it is spread in a world net by using, among other means, repeaters and Internet.
The amateur P25 communications are the sole object of the Multipsk decoding (professional communications are decoded but ignored). The P25 is considered as a "professional" mode by Multipsk (but the Ham decoding is not limited in time).
It is here only considered the data communication which summarizes to identifiers (callsigns). Note: the voice communication decoding is excluded because it needs an IMBE Codec.
For Hams and SWL, the P25 signal can be received: · either from the discriminator output of a classical VHF/UHF FM receiver via a direct connection to the PC sound card. However, the receiver must have a large reception bandwidth due to the high modulation speed, · or with a SdR receiver (FunCube Dongle, RTL SDR,...) and directly demodulated by Multipsk. It is the simplest solution.
Here is the WEB address where you can know where all P25 repeaters are located, with their frequencies, for each country: https://www.repeaterbook.com/repeaters/niche/index.php?mode=P-25
This mode is in freeware, so without time limitation.
See general specifications below.
Note about translation of Multipsk.exe and Clock .exe: the 4.42 version of Multipsk has been translated to Spanish by Joachin (EA4ZB), from French. See: http://f6cte.free.fr/Translation_files.htm.
73 Patrick
Description of the P25 mode Baud rate: 4800 (with 2 bits per symbol so 9600 bps)
Modulation : each double logic signal (dibit) directly modulates, through a raised cosine filter (to reduce the bandwidth needed), the VHF or UHF frequency in 4FSK (on about +/- 4.5 KHz). So this signal is received in base band after FM demodulation. It is also used a "CQPSK" modulation, which is demodulated as C4FM.
Reception mode: FM
Shape of pulse : raised cosine filter
Bandwidth : about 9 KHz
Detection and synchronization code: yes on 48 bits.
Codes: several codes are used (Hamming, BCH, Golay, Reed-Solomon...)
Interleaving : no
Scrambling: no
Transmission
Each "superframe" is composed of the following data units: Header / Logical link 1 / Logical link 2 / Logical link 1 / Logical link 2 / Terminator (with or without Link control).
Each data unit is composed of a unique frame synchronization word on 48 bits, followed by a network identifier on 64 bits giving among other information the data unit type, and finally a piece of information depending on the data unit. The lenght and the coding of each data unit are different. The main piece of information is, of course, the digitalized voice.
The pieces of information that interest Multipsk are the ones contained in the Logical link 1 unit and in the Terminator with Link control unit, because they carry the IDs (Source + Talk Group or Destination + Source).
Note: contrary to DMR, this is not a TDMA system as it is managed only one transmission.
For about the interface between your PC and your transceiver, see the paper "HOW_TO_DO_DIRECT_DSTAR_BETWEEN_HAMs_Rev_A.pdf" located in the http://f6cte.free.fr/DSTAR.ZIP file, but taking into account only the reception part (no P25 transmission by Multipsk).
|
||||
|
||||
ROS-HF 7 MHz ZS Net
#ros
Graham
Checking the ROS-HF user levels these days, on psk-map stat's ROS v6.7.3+CAT/Rptr V1.4 1 IZ8STM ROS v6.7.3/Rptr V1.4 2 IT9KYA, IZ8STM ROS v6.9.0+CAT/Rptr V1.4 2 ZS6DPL, ZR6PC ROS v6.9.0/Rptr V1.4 14 ZR6PC, ZR6EJH, ZS6BV, ZS4BC, ZS3P/4, ZS6GAX, ZS5UA, ZS2DRS, ZR6JAN, ZS6ADY, ZS6APB, ZS3P, ZS3PG, ZR5EE ROS v6.9.7/Rptr V1.4 1 ZS6ADR ROS v7.1.3/Rptr V1.4 1 LZ1XK ROS v7.4.0+CAT/Rptr V1.6 254 ROS v7.4.0/Rptr V1.6 342
|
||||
|
||||
Re: Signs of the FT8 curve flattening ?
Andrew OBrien
I even saw this
16:26:26 UTC QPSK125 802 Hz Not often you hear someone using QPSK, and then 125 . Among today's RSID hits 16:49 KZ1O CONTESTI 14073483 16:30 W5OTR CONTESTI 14073483 16:29 N7ESU PSK 14072202 16:15 N7RI PSK 14072859 16:14 N7ESU PSK 14072859 16:03 KG7D PSK 14072267 15:43 N4UM OLIVIA 14072977 15:34 KD5LPB OLIVIA 14072767 14:18 K5TED MFSK 14072854 13:37 WA5IEK OLIVIA 14072886 13:23 W5OTR CONTESTI 14073166 13:20 NR4A OLIVIA 14072498 12:56 KD5LPB OLIVIA 14072498 03:35 ZL1WN OLIVIA 14072487 03:32 K7TPN OLIVIA 14072487 03:18 zl1wn OLIVIA 14072487 02:42 zl1wn OLIVIA 14072487 02:41 KM6NFS OLIVIA 14072487 02:38 ZL1WN OLIVIA 14072487 01:44 W5ERX OLIVIA 14072132 00:45 AC6P OLIVIA 14072003 00:07 K0DXV OLIVIA 14073101 Andy K3UK
|
||||
|
||||
Re: Opera QSO party running on 7038
Graham
Long skip , would of been the description in the past ?
|
||||
|
||||
Re: Signs of the FT8 curve flattening ?
Andrew OBrien
Some RSID TX hits I detected while parked around 14071 , courtesy of Multipsk software
18:35 KI5UH PSK 14071541 18:26 2D0P PSK 14071541 18:25 OA4CN PSK 14071546 18:16 2D0PEY PSK 14071546 16:50 AD0XB OLIVIA 14071600 15:52 KC3FL PSK 14071723 15:35 KC3FL PSK 14071742 02:19 N0FPH THOR 14072235 02:16 zl1wn THOR 14072235 01:59 zl1wn THOR 14072240 01:35 zl1wn THOR 14072245 01:33 ZL1WN THOR 14072245 01:19 zl1t THOR 14072245 01:18 zl1wn THOR 14072245 22:41 NW7US OLIVIA 14072466 22:30 K4ZMR OLIVIA 14072498 22:21 NW7US OLIVIA 14072498 22:16 WB4QOJ OLIVIA 14072504 22:04 NW7US OLIVIA 14072498 22:01 K4ZMR OLIVIA 14072509 21:53 N1CL OLIVIA 14072509 21:52 NR4A OLIVIA 14072509 21:05 EA7EZ OLIVIA 14072520 20:49 NR4A OLIVIA 14072520 20:43 NV1O OLIVIA 14072525 20:33 NR4A OLIVIA 14072525 20:29 EA7EZ OLIVIA 14072723 20:22 NW7US OLIVIA 14056433 ReporterInitialize Success
|
||||
|
||||
Re: Signals on 7.070 +1500-3000hz
Andrew OBrien
I have you heard this since?
Andy K3UK
|
||||
|
||||
Signs of the FT8 curve flattening ?
Andrew OBrien
I like working FT8 from time to time but lament the decline in the use of other digital modes on HF. Lately however, I have seen what appears to be an increase in Olivia, Thor 8, and MFSK16 . Perhaps with many hams staying home, they are looking for more conversational modes. I had a nice QSO with Ross ZL1WN using Thor 8 on 20m late yesterday (my evening). The modes did well.
Andy K3UK
|
||||
|
||||
Re: Signals on 7.070 +1500-3000hz
Graham
Not the VARA modem apparently ,
looks like a arq system , with the short mid frame ?
|
||||
|
||||
Signals on 7.070 +1500-3000hz
I heard some strange signals tonight, about 1.5kHz wide and sharp. I've never heard anything like it before.
Any idea of what this may have been ?, 28 Mar ~ 0240z
|
||||
|
||||
Harmonics in audio Tx drive / side bands / Gray Noise
Graham
Posted to the RSGB tech group
By G3PLX Makes a very valid point , surrounding harmonics in TX audio drive , whilst using SSB transmitter for data level clipping is not the holy grail of clean signals , applicable to C / D & E pa's etc , where say the tones are 1500 hz , then the harmonic falls out of the pass band, but, for systems , using a wide spread of tones , then harmonics from the low 'set's can be in band . the phase disturbance exists with or without limiting , 73-Graham In reply to previous posts .. Let me try to explain it better. Say I have a 1 kHz tone with a second harmonic at 10%, going into a balanced modulator at 9 MHz, The output of that will be the two main F1+/- F2 components at 9001 and 8999, with two more at 9002 and 8998 at -20dB. Let's select only the upper sideband with a filter, leaving one big signal at 9001 and a smaller one at 9002 20dB down. Think of what this looks like on a phasor display. The main signal is a dot rotating in a circle of radius 1.0 around the origen and the small signal is a dot rotating in a circle of radius 0.1 around that. Not easy to visualise, so mentally de-spin the display so the main dot is stationary and it's easy then to see that the combined signal looks like a dot moving in a 0.1 radius circle around a point at a radius of 1. The combined signal is varying in amplitude between 0.9 and 1.1, and ALSO swinging in phase by +/-0.1 radian (+/-5.7 degrees). Remove the AM component by hard-limiting the signal (through a class C power amplifier) and the resulting signal is constant amplitude but the phase modulation remains. The output spectrum will be a carrier at 9001kHz with phase modulation sidebands 1 kHz either side at approximately -26dB. What was a single spurious tone at 9002 kHz at -20dB with a linear power amplifier, has become a pair of spurious tones at 9000 and 9002 at -26dB, if we remove the AM component with a saturated power amplifier. So hard limiting the RF output of an SSB transmitter fed with a distorted audio tone, does not clean up the resulting distortion on the RF output. It IS important to ensure that either (a) the audio tone generator is a pure sine wave or (b) that it's second harmonic lies outside the SSB filter passband. This will be true regardless of how the tone is keyed, whether FSK or two alternating on/off tones or one tone keyed on and off. 73 Peter G3PLX
|
||||
|
||||
Olivia is partying
#Olivia
Andrew OBrien
For the next few days I will be QRZ most of the day 1200-2359 UTC on 14107.5 ( 14106 dial ) Using Olivia 16/1000 with RSID.
Andy K3UK (FN02, New York)
|
||||
|
||||
Opera QSO party running on 7038
Graham
Opera QSO party running on 7038
WQ2H Running over the last week , with 5 and 10 watts on 7028 Op02 , as well as 1836 Op04 7 puting in some good ''qrp'' dx at the moment , 73-Graham g0nbd So far , making over to US east coast ........................................................................................................Kmt 2020-03-20 19:22:49 EA2B IN91MP WQ2H FN32XV 5.667 7.038 -18 Op2_||||||||||||||||_~18dB
2020-03-19 21:00:38 G4MDH IO91BN WQ2H FN32XV 5.176 7.038 -23 Op2_||||||_~23dB
2020-03-17 22:59:08 G0NBD IO83LK WQ2H FN32XV 5.039 1.836 -30 Op4__~30dB US to EU 2020-03-20 21:11:09 WQ2H FN32XV EA2B IN91MP 5.667 7.038 -24 Op2_||_~25dB
2020-03-19 20:29:54 WQ2H AA G0NBD IO83LK 0 7.038 -25 Op2_||_~25dB
2020-03-19 19:39:32 WQ2H FN32XV G4MDH IO91BN 5.176 7.038 -23 Op2_||||||_~23dB
Last 24 Hrs RX3DHR R3D-262/RA0 40m OPERA 6140 km 15:27:57
EA2B WQ2H 40m OPERA 5667 km 20:48:53
WQ2H G4MDH 40m OPERA 3217 miles 20:56:25
WQ2H G0NBD 40m OPERA 3132 miles 21:09:06
G0NBD WQ2H 40m OPERA 5040 km 21:04:01
EA2B RX3DHR 40m OPERA 3235 km 20:48:53
RX3DHR EA2B 40m OPERA 3234 km 20:30:47
R3KCC G0NBD 40m OPERA 3014 km 19:03:40
R3KCC G4MDH 40m OPERA 2994 km 19:03:41
RX3DHR G4MDH 40m OPERA 2700 km 21:16:24
G0NBD RX3DHR 40m OPERA 2696 km 20:17:31
RX3DHR G0NBD 40m OPERA 2695 km 20:20:16
G0NBD SV8RV 40m OPERA 2525 km 18:06:13
RX3DHR SV8RV 40m OPERA 2325 km 21:03:49
R3KCC SV8RV 40m OPERA 2242 km 18:22:05
EA2B SV8RV 40m OPERA 1912 km 20:42:39
G0NBD EA2B 40m OPERA 1319 km 20:04:58
EA2B G4MDH 40m OPERA 1104 km 20:42:38
G4MDH G4MDH 40m OPERA 2 km 17:48:25
Opera download link
|
||||
|