IK0VVE Max

Tentativo di ricezione eco dell’asteroide 2012 TC4

Questi giorni si avvicinerà alla Terra l’asteroide 2012 TC4 ad una distanza veramente minima per un oggetto spaziale, domani alle 7:42 ita il picco di massimo avvicinamento.

Con quasi le stesse modalità del sistema meteor scatter sto provando a ricevere sulla frequenza del GRAVES l’eco dell’asteroide che transiterà a circa 42000 Km da noi. L’esito della prova è alquanto incerto poiché l’asteroide ha un diametro di “soli” 20 metri e passerà prevalentemente nell’emisfero sud quindi un pò fuori dalla finestra del trasmettitore.

Alla solita pagina http://www.ik0vve.net/?page_id=745 è possibile, rumori vari permettendo, visualizzare alcuni grafici adattati per l’evento.
Il primo grafico in alto è lo spettro radio a 143.050 MHz, frequenza di trasmissione del GRAVES, il 24h meteor strip è stato adattato per una maggiore visualizzazione. Ogni strip è di sole 4 ore e non 24 e la larghezza di banda è di 5 kHz. Tutto questo dovrebbe far vedere, in caso di eco, una linea curva che dalle frequenze più alte scende fino a scomparire sotto lo zero.

Vedremo domani se e cosa il sistema avrà registrato.

NDB: photo of ZRA antenna

During last holidays in Croatia I made a photo about a Marconi-T antenna in the village of Kakma, here the photo:

The antenna consists of a pair of towers about 20 meters high with a 2 wires Marconi-T antenna. Under the vertical wires is there a little house where the transmitter is positioned. It’s curious that the antenna is very close to the road and a lot of near trees surround it, it’s not located at the top of the hill but probably for its work is enough efficient.

The coordinates are 43° 59′ 50” N – 15° 29′ 47” E, transmission frequency is: 330 kHz. It’s a middle power NDB with a nominal range of 50 NM. More informations on Zadar airport web site: http://www.zadar-airport.hr/en/radio-navigation

Google maps: https://www.google.com/maps/@43.9973652,15.4968233,378m/data=!3m1!1e3?hl=en-EN

MF tests with the sunlight

This morning, until about 1 o’clock pm local time, I tried to increase the transmission power from 50W to about 180W to see if the homemade radial matcher commutator can resist or smoke…
Well, it endured! During the tests i’ve been looking on wspr.net page and with a nice surprice I’ve seen that my signal was captured not only 246 km far from my TX by IK6BAK but also from DJ0ABR station even 800 and more km far! I think that DJ0ABR has a very low noise at the receiver front end.

I’ll be on the air tonight for a first “hi power” transmission. Stay tuned!

Timestamp	Call	MHz	SNR	Grid	Pwr	Reporter	RGrid	km	az
2017-10-05 11:20	IK0VVE	0.475757	-23	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 11:10	IK0VVE	0.475757	-23	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 11:00	IK0VVE	0.475757	-24	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 10:50	IK0VVE	0.475757	-23	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 10:40	IK0VVE	0.475757	-23	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 10:30	IK0VVE	0.475757	-24	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 10:20	IK0VVE	0.475757	-25	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 10:10	IK0VVE	0.475757	-24	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 10:00	IK0VVE	0.475757	-23	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 10:00	IK0VVE	0.475757	-28	JN61km	0.2	DJ0ABR	JN68nt	811	1
2017-10-05 09:50	IK0VVE	0.475757	-24	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 09:40	IK0VVE	0.475757	-23	JN61km	0.2	IK6BAK	JN63kr	246	0
2017-10-05 09:30	IK0VVE	0.475757	-24	JN61km	0.2	IK6BAK	JN63kr	246	0

MF TX season started!

Last night I’ve been transmitting for the first time after the summer period. A new look to the the TX antenna was made to simplify the shape and get more gain. Now the hat is about 16 meters long and the vertical side is about 9 meters high.

The 6 wires of vertical slope are almost invisible on the left.

This are the stations that copied my signal in a couple of hours of transmission:

But a new “masterpiece” was build to remote tune the antenna in addition to the remote control of the variometer by a stepper motor, I’ve build a multi rotary switch to commutate the coils of antenna transformer without going out to the balcony changing the correct tip where to connect the antenna to get the right impedence. Soon a photo on these pages.

Log for stations over 1000 Km (61 different station overall):

Timestamp	Call	MHz	SNR	Grid	Pwr	Reporter	RGrid	km	az
2017-10-03 20:40	IK0VVE	0.475757	-28	JN61km	0.2	EA8BFK	IL38bo	2809	248
2017-10-03 20:40	IK0VVE	0.475757	-21	JN61km	0.2	SM2DJK	KP03au	2526	8
2017-10-03 19:40	IK0VVE	0.475756	-24	JN61km	0.2	OH2EAT	KP20xw	2333	18
2017-10-03 20:40	IK0VVE	0.475741	-14	JN61km	0.2	SM3LNM	JP82qg	2327	6
2017-10-03 20:40	IK0VVE	0.475758	-22	JN61km	0.2	EI8JK	IO51do	2046	311
2017-10-03 20:30	IK0VVE	0.475746	-24	JN61km	0.2	LA8AV	JO59cs	2038	356
2017-10-03 20:30	IK0VVE	0.475757	-27	JN61km	0.2	LA6LU	JO59eq	2027	356
2017-10-03 19:20	IK0VVE	0.475757	-22	JN61km	0.2	LA3EQ	JO28xj	1938	348
2017-10-03 20:40	IK0VVE	0.475757	-27	JN61km	0.2	G0LUJ/1	IO83ls	1802	324
2017-10-03 19:10	IK0VVE	0.475757	-28	JN61km	0.2	G0LUJ/2	IO83ls	1802	324
2017-10-03 19:10	IK0VVE	0.475757	-24	JN61km	0.2	G0MJI	IO83ni	1763	324
2017-10-03 20:40	IK0VVE	0.475757	-24	JN61km	0.2	G4CPD	IO94hc	1751	328
2017-10-03 19:20	IK0VVE	0.475758	-23	JN61km	0.2	GW3UCJ	IO81cr	1698	318
2017-10-03 20:40	IK0VVE	0.475757	-22	JN61km	0.2	EA7HPM	IM67xj	1684	260
2017-10-03 20:40	IK0VVE	0.475758	-15	JN61km	0.2	G8HUH	IO81mg	1622	317
2017-10-03 20:40	IK0VVE	0.475757	-20	JN61km	0.2	G4ETG	IO92uc	1541	324
2017-10-03 20:40	IK0VVE	0.475758	-15	JN61km	0.2	G4ZFQ	IO90ir	1492	318
2017-10-03 20:40	IK0VVE	0.475761	-16	JN61km	0.2	G7UHT	IO90jr	1487	318
2017-10-03 19:10	IK0VVE	0.475757	-19	JN61km	0.2	G6AVK	JO01ho	1457	324
2017-10-03 20:40	IK0VVE	0.475754	-22	JN61km	0.2	DF2FF	JO44th	1442	352
2017-10-03 20:00	IK0VVE	0.475757	-14	JN61km	0.2	PA0A	JO33de	1387	341
2017-10-03 20:40	IK0VVE	0.475757	-23	JN61km	0.2	PA0SLT	JO33kg	1381	343
2017-10-03 20:40	IK0VVE	0.475757	-16	JN61km	0.2	PD0SBS	JO33le	1371	343
2017-10-03 19:20	IK0VVE	0.475757	-26	JN61km	0.2	PA2GP	JO33hb	1366	342
2017-10-03 20:40	IK0VVE	0.475762	-22	JN61km	0.2	PA7EY	JO22jj	1354	336
2017-10-03 19:20	IK0VVE	0.475757	-19	JN61km	0.2	SP5XSB	KO02ld	1330	25
2017-10-03 19:30	IK0VVE	0.475758	-30	JN61km	0.2	PA0EHG	JO22hb	1328	335
2017-10-03 20:40	IK0VVE	0.475757	-19	JN61km	0.2	DL0HT	JO43jb	1319	348
2017-10-03 19:20	IK0VVE	0.475759	-12	JN61km	0.2	PA0RDT	JO11tm	1316	331
2017-10-03 20:40	IK0VVE	0.475759	-24	JN61km	0.2	DL/PA0EHG	JO32sq	1305	344
2017-10-03 20:40	IK0VVE	0.475757	-13	JN61km	0.2	DJ2FS	JO62wx	1276	3
2017-10-03 20:40	IK0VVE	0.475757	-24	JN61km	0.2	PI4THT	JO32kf	1274	341
2017-10-03 20:30	IK0VVE	0.475757	-20	JN61km	0.2	PE1IWT	JO32kf	1274	341
2017-10-03 20:40	IK0VVE	0.475759	-19	JN61km	0.2	EB1LO	IN82sk	1270	280
2017-10-03 20:40	IK0VVE	0.475756	-26	JN61km	0.2	PA0MLC	JO31aw	1269	338
2017-10-03 20:40	IK0VVE	0.475759	-18	JN61km	0.2	DF5FH	JO42um	1246	350
2017-10-03 20:40	IK0VVE	0.475757	-16	JN61km	0.2	EA2HB	IN93ah	1232	284
2017-10-03 20:40	IK0VVE	0.475756	-23	JN61km	0.2	DL6OW-R	JO31kk	1194	340
2017-10-03 19:10	IK0VVE	0.475760	-16	JN61km	0.2	ON8IM	JO20ls	1194	332
2017-10-03 20:30	IK0VVE	0.475758	-25	JN61km	0.2	DC5AL-R	JO31lk	1191	340
2017-10-03 20:20	IK0VVE	0.475760	-23	JN61km	0.2	DC0DX	JO31lk	1191	340
2017-10-03 20:30	IK0VVE	0.475756	-14	JN61km	0.2	DF2JP	JO31hh	1188	338
2017-10-03 20:40	IK0VVE	0.475757	-10	JN61km	0.2	ON7ZO	JO20ei	1180	329
2017-10-03 20:40	IK0VVE	0.475758	-28	JN61km	0.2	DL4EAI	JO31je	1171	339
2017-10-03 20:40	IK0VVE	0.475759	-26	JN61km	0.2	EA5DOM-1	IM98xn	1146	258
2017-10-03 19:20	IK0VVE	0.475758	-28	JN61km	0.2	EA5AU	IM99tl	1142	263
2017-10-03 20:40	IK0VVE	0.475754	-13	JN61km	0.2	DL6II	JO30nx	1140	339
2017-10-03 20:40	IK0VVE	0.475759	-11	JN61km	0.2	F1AFJ	JN06ht	1139	305

Perseidi 2017, report un pò in ritardo

Solo ora sono riuscito a terminare la stesura del report sulle Perseidi 2017. Purtroppo ancora ho problemi nel far lavorare assieme SpectrumLab con RMob con la conseguenza che i dati degli eventi non si distribuiscono per ore ma sono raggruppati in grossi “ammassi”, solo grazie all’indispensabile e preziosissimo aiuto del mio amico e collega Luca Francescutti siamo riusciti a venirne a capo.
Quello che segue è il grafico relativo al periodo delle Perseidi partendo dal giorno 8 Agosto per avere un riferimento di come erano gli eventi di fondo prima di questo sciame. Certo è che l’attività era già alta probabilmente a causa di alcuni sciami minori come le Delta Acquaridi.

Dalla tabella a lato si può chiaramente vedere che i giorni di maggiore attività sono stati il 12 ed il 13 Agosto anche se il giorno 11 ci regalava già parecchi echi.

Per questo sciame ho effettuato dei cambiamenti sul sistema di ricezione, non ho usato la chiavetta RTL ma l’Elad FDM-S1 con filtro passabanda centrato sulla frequenza del GRAVES. La cosa che però ha elevato moltissimo il numero di echi ricevuti è il cambio di polarizzazione della 8 elementi LPDA passando da orizzontale a verticale. Confrontando con i dati dello scorso anno (non sono in rete) abbiamo numeri notevolmente più alti. Anche dal precedente post con video in timelapse è possibile vedere l’enorme quantità di echi catturati arrivando per il giorno 12 a ben 2109 con due picchi di 127 echi in due ore diverse della mattinata.

Dalle immagini catturate ci sono stati degli echi veramente interessanti e lunghi. Di seguito un secondo grafico sull’andamento continuo nei sette giorni.

Di seguito link ad altri amici sulle Perseidi 2017:

IK0OZK Renato
IU3IOU Giorgio
I55387FI Daniele
Massimo

My Perseid 2017 time lapse video

NEO M8N U-Blox GPS receiver

Finally I’ve had some free time to play with my new GPS receiver, a NEO M8N.

This nice and cheap object arrived to me over a little PCB where other components are positioned for an easier and fast utilization. The rx-tx serial data are 3.3 V level, so a converter is needed for a correct work. I’ve used a USB converter that provides the 5 Volt DC for the 3.3 Volt board regulator.

To configure the NEO M8N I’ve used U-Center, the software is freely available at U-Blox website.

At first start the power LED was on and after a while also the TimePulse LED began to blink.

Despite I used it in an indoor ambient has been quickly possible to receive a lot of satellites.

This GPS receiver will be used to discipline my VLF to MF receivers thanks to the possibility to change the TimePulse period configuring it by U-Center software. I’ve tried to change the frequency measuring it by an oscilloscope. Here follows some images of the test.

A first test at 136 kHz with a low duty cycle. I’ve tried it at the maximum frequency of 10 MHz and the result seems to be good looking also to its linearity.

Lately other tests with 50% duty cycle at some interesting frequency:

To set a decimal frequency we need to change the frequency setup to period setup, so it will be possible to write a very sharp frequency till to nHz’s. For example I’ve tried to set 8270.005 Hz, whose period is 120.918911 us (microSeconds). Minimum frequency reached is 0.01 Hz with a possible accuracy of 0.1 nHz (nanoHz)!

First reception on 8270 Hz

Finally, thanks to Stefan DK7FC, I’ve my first “human” signal on 8 kHz band.
Stefan was active for all the last week-end on the band to give me a chance to receive his signal, and pixel after pixel the signal apeared in this way:
A well marked peak exactly on 8270.005 Hz shows the integration of the signal after many hours of transmission.

The distance between Stefan and me is about 940 Km, not bat at all! Stefan helped me to fine “tune” Spectrum Lab software to optimize the system for the best performance. As antenna I’ve used my loop oriented towards Heidelberg.

I think that other works, for a better receiving, could be done.

Almost ready for VLF again

Ready again to receive VLF with my new loop. At the moment the antenna is located on the roof under the TX antenna for MF-LF.

The preamplifier circuit comes from the easyloop of VLF.IT with an OP27 and few others components.

The antenna is composed by 32 turns of 0.15 mm dia. for a total lenght of over 200 meters. No screen has been applied around the wires.

Power supplied from a 12 V battery the signal goes down to the station by a little dual coaxial cable for submergible cameras (video+PS).

Just before the input to the audio board I’ve used a 50:600 Ohm home made trafo to optimize the signal.

This solution give me less noise and more signal.

Next step will be to insert the GPS to one of the audio channel to discipline by Spectrum Lab the audio board and get a stable and precise frequency.

Under here an image of this afternoon.

I still have an unknown noise on 10KHz.

630m pirate?

Tonight I’ve decided to try QRSS on MF and while I was transmitting I’ve seen on DK7FC grabbers a strange signal between mine and IK1HGI’s. The call was C7MW which prefix is allocated to the World Meteorological Organization. With Stefan’s RDF spectrogram is possible to see on the next picture that signal comes from E/W direction.

Any news?

JARTS WW RTTY Contest
0000Z, Oct 21 to 2400Z, Oct 22
Araucaria World Wide VHF Contest
0000Z, Oct 21 to 1600Z, Oct 22
10-10 Int. Fall Contest, CW
0001Z, Oct 21 to 2359Z, Oct 22
RCB XYL Test
0700Z-2159Z, Oct 21
New York QSO Party
1400Z, Oct 21 to 0200Z, Oct 22
Worked All Germany Contest
1500Z, Oct 21 to 1459Z, Oct 22
Stew Perry Topband Challenge
1500Z, Oct 21 to 1500Z, Oct 22
South Dakota QSO Party
1800Z, Oct 21 to 1800Z, Oct 22
Feld Hell Sprint
2000Z-2359Z, Oct 21
Illinois QSO Party
1700Z, Oct 22 to 0100Z, Oct 23

IK0VVE Max

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