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Teme - AD6IW

 Str: 1 ... 10 11 [12] 13
166
Test / Odg: ATV TX 13/23cm
«  : 24. Siječanj. 2009, 17:19:02 »
Patrik,

strpi se malo, u pripremi je novi 23cm/13cm transverter,
sa novim konceptom i boljim performansama.
Upravo radim firmware ali trenutno  sam QRL

ad6iw

167
Test / Odg: ATV TX na 2,5 GHz
«  : 09. Prosinac. 2008, 20:14:45 »
Probaj sa lakom kada zavrsis i testiras plocicu. Lak mozes skinuti sa acetonom.
Moguce je da lak poveca leakage current u PLL loop filteru, sto se moze odraziti
na spurs level. Neznatan je utjecaj na RF na 2.5GHz, jer ne koristis
mikrostrip filtere, splitere i sl.
Bolje rijesenje je da tinujes plocicu.
 
ad6iw

168
Test / Odg: magic tee
«  : 11. Studeni. 2008, 02:32:01 »
Load na e-bay je OK, ali je malo pricy ???
Mozda mozes da stavis absorber, (to je ona crna spuzva ili siva guma u uW uredjajima)
u wg port pa da glumi dummy load, pod uslovom da ne koristis veliku snagu npr vise od desetak vati.
Ako imas power meter onda to mozes jednostavno testirati.

73
ad6iw

169
Test / Odg: Coaxial relay
«  : 28. Rujan. 2008, 20:49:28 »
Zamjena je BCV46.
Mikroprocesor ? Overkill ???
Treba ti dva tranzistora, eventualno jedan inverter i stvar radi.
Da igla nije pronadjena prije 2000 godina danas bi imala dva mikroprocesora
i ko zna sta jos

AD6IW

170
EME / EME
«  : 13. Srpanj. 2008, 15:06:47 »
Hello
Yesterday I took a direct hit from lighting to my antenna system.  So far
I lost my SDR Flex Radio, power supply, controller box in radio room for
Az and El.  Also a computer and the control boards on the array for Az
and El that are W5LBT design.  Don't know if it got the absolute encoder
yet.  This is going to take a while to get everything fixed.  I will be
back.


KB8RQ, Gary
Info AD6IW

171
Test / Odg: SRA2 mixer
«  : 04. Lipanj. 2008, 21:33:02 »
Adam,

Mozda je francuz koristio SRA-2,5  ???
Stari Anzac mixeri su u nesto vecem kucistu.


ad6iw

172
EME / EME ekspedicije
«  : 20. Svibanj. 2008, 18:16:12 »
OK1DFC EME raspored aktivnosti


4O/OK1DFC
04.06.08 - 03:00 - 19:00 UTC 432 MHz
05.06.08 - 04:00 - 20:00 UTC 1296 MHz

Z3/OK1DFC
07.06.08 - 05:40 - 20:40 UTC 432 MHz
08.06.08 - 06:20 - 21:20 UTC 1296 MHz

all will be on web when come back from LZ

Regards

Zdenek - OK1DFC
www.ok1dfc.com
QRV 144 - 1296 MHz EME
QRO and 10m DISH
WAC 432 - 1296 MHz


info by ad6iw

173
EME / NA6MF EME
«  : 13. Travanj. 2008, 18:15:26 »
NA6MF NASA Moffet Field California April 12th 2008
EME

174
Test / NASA EME
«  : 13. Travanj. 2008, 17:51:14 »
April 12th NA6MF Moffet field California

175
Test / NA6MF EME Apr. 12th
«  : 13. Travanj. 2008, 08:23:09 »
no comments

176
Test / Odg: Dobio sam novu peglu
«  : 06. Travanj. 2008, 16:09:40 »
Rolando,

Ako koristis dva filtera sa istom propusnom sirinom, onda je ukupna propusna sirina ista kao i sa jednim,
samo sto su ivice strmije, a gubici veci.
Martin, zabiljezi frekvencije, nizu i visu gdje ti snaga padne za 3dB, ili na pola, a mjeri
snagu sa power meter-om i vjestackim opterecenjem .To je onda propusna sirina za - 3dB.
Mozes izmjeriti IL gubitke u filteru sa power meter-om, izmjeri snagu bez filtera, pa onda
ubaci filter i vidi razliku, lako se preracuna u dB.
Postavi SWR meter na ulaz filtera i izmjeri (ili podesi) VSWR), sa zakljucenim
vjestackim opterecenjem, pa zamjeni ulaz/izlaz i ponovi postupak.
Promjenom frekvencije ce se mjenjati i VSWR.
Zabiljezi sva mjerenja i frekvencije, stavi u Excell i isplotaj.
Jednostavan network analizator!
 
AD6IW

177
UKV tehnika / indikator za antenu
«  : 20. Ožujak. 2008, 19:49:22 »
Guy's

Primjetio sam da ima interesa za precizno podesavanje i indikaciju antena.
Ovo je koristan link. MA2 i MA3 su vrlo precizni i jeftini magnetni enkoderi za AZ/EL,
sa analognim outputom, ili PWM.
Samo za elevaciju moze se koristiti MEMS akcelerator od ADI,
vrlo jednostavno i jeftino.

http://www.usdigital.com/products/ma2/
http://www.austriamicrosystems.com/03products/20_rotary_encoders.htm
http://www.analog.com/en/subCat/0,2879,764%255F800%255F0%255F%255F0%255F,00.html

178
Test / Odg: MRF-422 ispod poklopca
«  : 07. Veljača. 2008, 21:51:21 »
Pozdrav Marjane,

Mozda se pitas sta trenutno radim. Imam gripu i sjedim kod kuce za kompjuterom,
dok radni narod sljaka, i chatam na VHFNET sa nasom rajom. Ja radim u R&D u Agilent Technologies, former HP.
Candy store!



179
UKV tehnika / QRP
«  : 31. Siječanj. 2008, 04:14:34 »

180
MS / Quadrantid MS
«  : 03. Siječanj. 2008, 18:19:18 »


From WEB
Joe Rao
SPACE.com Skywatching Columnist
SPACE.com
2 hours, 45 minutes ago
 


The Quadrantid meteor shower is due to reach maximum in the predawn hours of Friday, Jan. 4. The Quadrantids are notoriously unpredictable, but if any year promises a fine display, this could be it.

ADVERTISEMENT
 
Indeed, this may end up being the best meteor shower of 2008.


The Quadrantid (pronounced KWA-dran-tid) meteor shower provides one of the most intense annual meteor displays, with a brief, sharp maximum lasting but a few hours. The timing of peak activity favors Western Europe and eastern North America. Weather permitting, skywatchers in rural locations could see one or two shooting stars every minute during the peak.


Annual challenge


Each year, many factors combine to make the peak of this display difficult to observe. 

Peak intensity is exceedingly sharp: meteor rates exceed one-half of their highest value for only about 8-hours (compared to two days for the August Perseids).  This means that the stream of particles that produce this shower is a narrow one – apparently derived within the last 500 years from a small comet.
As viewed from mid-northern latitudes, we have to get up before dawn to see the Quadrantids at their best. This is because the radiant – that part of the sky from where the meteors to emanate – is down low on the northern horizon until about midnight, rising slowly higher as the night progresses.  The growing light of dawn ends meteor observing usually by around 7 a.m.  So, if the "Quads" are to be seen at all, some part of that 8-hour active period must fall between 2 and 7 a.m.
In one out of every three years, bright moonlight spoils the view.
Over northern latitudes, early January often sees inclement/unsettled weather.

It is not surprising then, that the Quadrantids are not as well-known as some of the other annual meteor showers, but 2008 may prove to be an unusual exception.   


Exception this year


According to the International Meteor Organization, maximum activity this year is expected on Friday 1:40 a.m. Eastern Standard Time. 


For those in the eastern United States, the radiant will be about one-quarter of the way up in the east-northeast sky.  The farther to the north and east you go, the higher in the sky the radiant will be.  To the south and west the radiant will be lower and the meteors will be fewer. 


From Western Europe, the radiant will soar high in the east as the peak arrives just as morning twilight intervenes.


Quadrantid meteors are described as bright and bluish with long silvery trains.  Some years produce a mere handful, but for favorably placed observers, this could be a shower to remember; at greatest activity, Quadrantid rates will likely range from 30 to 60 per hour for eastern parts of the U.S. and Canada, to 60 to 120 per hour for Western Europe. 


Across central and western parts of North America, the shower's sharp peak will have already passed and meteor activity will be rapidly diminishing by the time the radiant has a chance to get very high in the northeastern sky.  Nonetheless, hourly rates of perhaps 15 to 30 may still be seen. 


The moon will be a waning crescent, not rising until after 4 a.m. and will add very little light to the sky


HNY

Goran AD6IW

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