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366 THE SHORT WAVE MAGAZINE September, 1983

BANDS

NORMAN FITCH, G3FPK

Oscar Ten

AT the end of last montłTs marathon edition, it was stated that AMSAT’s Oscar 10 satellite had bcen placcd into a new orbit, a second firing of the on-board rocket motor being planned for later. The attempt was madę at 0031 on July 26 but turned out to be the “darnp squib” phenomenon as there was no ignition at all. It seems that there was no fuel left, it either having all been spent during the first, longer-t han-planned firing, or, if there was any left, it must have leaked away due to possible damage. This damage occurred when A-O-10 was ejected from the third stage of the ARIA NE launch vehiclc and was entirely the fault of the European Space Agency, which has apologised to AMSAT for this mishap.

The net result is that the orbit is inclined at only 26.12° to the equator which is less than half that planned. The period is just under 1 lh. 40m. and the satellite will be in rangę from theU.K. foruptotenhoursfor orbits at the maximum e!evation of about 55°. The perigee of nearly 4,000 kms. is morę than lwice the desired distance and means that the satellite will spend much morę time in the intense Van Allen radiation belt. The long term effects of this could affect the working life of the electronics, but only time will tell.

The U-transponder was switched on at 1430 on August 6 to start a new era of amateur satellite communication. The maximum theoretical rangę is somcwhat over 18,000 kms. which means that at some times, it will be possible to contact Australian stations from the U.K. and probably many exotic, Pacific areas. During the 2m. AMSAT net run by Ron Isaacs, G8CSI, in the London area on Aug. 7, it was stated that, sińce the satellite was not in the correct attitude, the lower gain, omni-directional antennas were in use. Even so, Trevor Stockill, G4GPQ, using about 800w. e.r.p., heard his signal at S2 and worked JY9CF, DJ9PC, OE3EFS and FI ANY. No doubt, by the time this is read, many real DX contacts will have been madę.

The current satellite calendar was received at the beginning of August and includes /l-O-/0predictions in the form of AOS and LOS times with respective azimuths, and the time, azimuth and maximum elevation figures for each available orbit. It also contains the band plan which suggests communication uplink from 435.035 to 435.155 MHz, the inverted downlink QRGs being from 145.965 to 145.845 MHz. AMSA T-UK CW and RTTY bulletins are on 145.825 MHz and SSB bulletins on 145.975 and 145.970 MHz The General beacon is on 145.810 MHz and the Engineering one on 145.987 MHz. The current issue of Oscar News contains a comprehensive supplement on the new “bird”.

A long while ago in this feature, your scribe mentioned the possible problem in monitoring one’s own signal from a very distant satellite. G4GPQ found this to be a very real problem, so much so that Trevor*s solution was to turn down the receiver AF gain control while talking. With a delay of up to 300 milliseconds, the effect is quite disorientating and it is just as bad when sending CW and hearing it coming back slightly delayed, particularly if you have sidetone!

Readers are urged to send in reports of O-10 activities — and s.w.l. reports are just as interesting as those from licensed amateurs — so that a detailed assessment can be madę of the problems and advantages of this new type of satellite orbit. A description of the TX and RX, plus antennas used for the experiments, will be of much help.

Other Space News

It was only a matter of time beforc an amateur radio operator was included in the crew of one of N.A.S.A.’s space shuttle missions. Aboard mission STS-9 will be Dr. Owen Garriott, W5LFL, who has permission to operate a 2m. transceiver from the orbiter. He will run about five watts of FM and, while over Region 1, will probably use 145.550 MHz (S22), but this will be confirmed later. The launch has been put back and is presently scheduled for October 28.

On the E-M-E scene, Clive Penna, G3POI, (Kent) worked KG6DX in Guam on June 19 for 2m. country no. 61. Pete Etheridge, G4ERG, (Humberside) is one of a growing number of 2m. operators to have worked Dave OLean, K1WHS, in Maine. Pete’s PA uses a pair of the popular 4CX250B valves and he now has a Kenpro KR500 elevation rotator on his antenna, which is a single 16-ele. Yagi. He has heard fifteen stations via the Moon, the loudest being 120DI who feeds his 16 times 20-ele. array with a mere two kilowatts! G3POI reports that the W6JKV expedition to Tl 9 “lost their antennas”, while K6MYC/HR6 had power supply problems.

Awards News

Congratulations to Garry Clark, G6FSH, from Rad ford, Coventry in the West Midlands, who was elected member no. 358 of the 2m. VHF Century Club on July 15. He passed the R.A.E. in May, 1981 and got his licence in the following October, starting off with a Mizuho SB2-M one watt, SSB transceiver feeding a dipole. Later a IOw amplifier was added and the antenna changed to a 5-ele. Yagi. Next came a Yaesu FT-290 and 8-ele. Yagi at lOOft. a.g.l. Following a move last March, the antenna is now an 11-ele. at 35ft. with a 15-ele. 70cm. beam already up for futurę use. Garry operates on RTTY and also operates on 3cm. using a 3mw transceiver, home madę, and 18 inch dish. Futurę plans include 70cm. and possibly 23cm. operating, and taking the morse test if his wife has passed her R.A.E.!

Beacon Notes

On 2m., the Lannion beacon, FX3THF, is operational again on 144.905 MHz from YI13d. It bcams cast towards Paris so is not a very strong signal in the British Isles. From the Azores group of islands, CT2EE operates a beacon on 144.150 MHz when there is a possibility of £’$ propagation. He listens on 28.885 MHz in the lOm. band.

Mikę Hearscy, G8ATK, reports that the building on which 23cm. beacon GB3FRS on 1,296.850 MHz, is installed was struck by lightning in a recent storm. Following this, the output from the station was only 1097o of the normal value.

Contests

The weekend Sept. 3/4 sees a major event, the IARU Region 1 VHF (i.e. 144 MHz) Contest from 1400 to 1400 GMT. This is in two sections:— Single-op. operated by the licensee only (no club stations) and All-other stations. Exchanges to comprise report/serial no. and QTH locator with scoring at one point per kilometre. The RSGB’s 144 MHz Trophy and SWL event runs concurrently with the same rules except that the usual radial ring scoring system is used. Notę that there is no need to give this, “23 km. east northeast of Llansantffraid-ym-mechain, Powys’’ nonsense.

On Sept. 11/12, from 1800-1200 GMT, there is the International ATV Contest on 432, 1,260 MHz and 10 GHz. Exchanges to be a four figurę group of your own choice on video only, plus cali, QTHL and serial no. on video or telephony. Scoring is 2 pts. per kilometre for two-way QSOs and half that for one-way contacts. Entries to G3VZV (QTHR) by Sept. 30.

The Cray Valley Radio Socieiy is promoting an activity day on Sept. 18 with a 432 MHz contest from 0700-1200 GMT, and a 144 MHz event from 1400-1700 GMT. There is a maximum power limit of 100 watts e.r.p., and a “novice“ section