CLUB MEETINGS
Regular Meetings: 2nd Wednesday of each month, 12 noon, 238-543. Open. to all.
Board of Directors: 4th Wednesday of seek mouth# 12 noon, 198-111. Open to all club ambers.
AMSAT-OSCAR 7 NEARS LAUNCH de W6EJJ
AMSAT-OSCAR 7, the seventh satellite built by and for radio amateurs, in being readied for an October 29 launch from NASA Western Test Range. The launch window is 1711-1721 GMT. For latest info, check into the AMSAT West Coast net on 3850 kHz at 7 pm PDT. This net normally meets on Monday nights but status information will be available nightly during the launch period.
On launch day, countdown information will be transmitted by Vandenberg AFB club station, W6AB on 14240 kHz. Launch and status information will be available on the following frequencies: 3850, 7280, 14280 and 21280 kHz. After ejection from the launch vehicle, the satellite's 435 mHz telemetry beacon will be turned on to transmit mores code telemetry. AMSAT-OSCAR 7 will not be turned on for normal communications until at least 24 hours after ejection in order to assess the operating health of the spacecraft.
AMSAT-OSCAR 7 REFERENCE DATA:
Frequencies:
Two to ten meter translator.
Input 145.850 to 145.950 mHz
Output 29.40 to 29.50 mHz70 cm to two meter translator.
Input 432-125 to 432-175 offs
Output 145.975 to 145.925 mHz
Output passband is INVERTED.
Beacon output at 145.975 mHz
Additional beacons at 435.1 mHz and 2304.1 mHz (The FCC has notified AMSAT that the 2304 mHz beacon should be "prevented from transmitting" until further notice.)
Operating Modes:
Mode A. 2 to 10 motor translator ON. 29.502 mHz beacon 02 (transmitting 20 wpm Mores code telemetry or codestore info). 435.1 mHz beacon operable (normally ON. transmitting 850 Hz FSK teletype telemetry).
Mode B. 70 cm to 2 meter translator ON (high power nods). 145.975 mHz beacon ON (modulated as per 29*502 beacon).
Mode C. 70 cm to 2 meter translator ON (quarter power mode). 145.975 mHz beacon ON per mode B.
Mode D. Recharge mode. Both translators OFF. 435 mHz beacon operable (Commanded on for telemetry readout)
Operating Schedule: (Planned after initial spacecraft checkout)
Mode A. Sunday, Tuesday and Friday
Mode B. Monday, Thursday and Saturday
Mode D or special experiments on Wednesday
Planned Orbit:
Similar to that of OSCAR 6; 1460 km altitude circular orbit, 102 degree inclination (retrograde, sun-synchronous orbit), period or 115 minutes, about 1/2 orbit (1 hour) out of phase with the OSCAR 6 orbit.
For additional info, see Feb 1974 QST. The following information Is from AMSAT NEWSLETTER for Sept 1974:
SPACECRAFT DESCRIPTION
AMSAT-OSCAR 7 contains two basic experimental repeater packages, redundant command systems, two experimental telemetry systems, and a store-and-forward message storage unit. The spacecraft in solar powered, weighs 65 pounds, and has a three-year anticipated lifetime. It contains beacons on 29.50, 145.98, 435.10 and 2304.1 MHz.
Communications Repeaters
Two types of communications repeaters are aboard the spacecraft, only one of which operates at a time. The first repeater is a higher power, two-watt version of the one-watt two-to-ten motor linear repeater that flow on the OSCAR 6 mission. This nit receives uplink signals between 145.85 and 145.95 MHz, and retransmits them between 29.4 mid 29.5 MHz an the downlink. A 200 milliwatt telemetry beacon provides telemetry data on 29.502 MHz.* Approximately -100 dBm is required at the repeater input terminals for an output of 1 watt. This corresponds to an eirp from the ground of 90 watts for a distance to the satellite of 2,000 miles and a polarization mismatch of 3 dB.
The second repeater, constructed by AMSAT Deutschland e.V., AMSAT's affiliate in Marbach, West Germany, is a 40-kHz* bandwidth linear repeater. It employs an 8-watt PEP power amplifier using the envelope elimination and restoration technique to maintain linear operation over a wide dynamic range with high efficiency. This repeater has an uplink from 432.125 to 432.175 MHz, and a downlink from 145.925 to 145.975 MHz. Since the uplink band in shared with the radiolocation service, an experimental pulse suppression circuit is incorporated in the repeater to reduce the effects of wideband pulsed radar interference in the uplink. Developmental versions of this repeater have flown in high-altitude balloon experiments in Germany, and aircraft flight tests of the repeater prototype unit. A 200 milliwatt telemetry beacon on 145.975' provides telemetry data. Approximately So W.*eirp is required to produce 3 watts of repeater output at a range of 2,000 miles assuming.& polarization mismatch of 3 db.
The two repeaters are operated alternately by means of a timer arrangement, but repeater selection and output power control can also be accomplished by ground command. Each of the repeaters includes a keyed telemetry beacon at the upper edge of the downlink passband to provide housekeeping data and to provide a frequency and amplitude reference marker to assist the amateur in antenna pointing, Doppler frequency compensation, and setting uplink power level. The cross-band 146-to-29.5 and 432-to-146 KNO design of the two repeaters will permit the amateur to monitor his own downlink signal easily, and consequently, he can adjust his power and frequency to continually compensate for changing path loss, repeater loading and Doppler shift.
Command System
Redundant command decoders of a design similar to the unit proven highly successful in OSCAR 6 will be flown. The decoder has provisions for 35 separate functions, and is designed to provide a reliable means of controlling the emissions of the repeaters, beacons and other experiments aboard the spacecraft.
Telemetry and Message Storage Systems
AMSAT-OSCAR 7 contains two experimental telemetry systems designed for use with simple ground terminal equipment. The first system, developed by the WIA-Project Australis group in Australia, telemeters 60 parameters in 850-Hz shift, 60 WPM five-level Baudot teletype code to permit printout on standard teletype equipment in a format readily convertible for direct processing by small digital computer. The second system telemeters 24 parameters as numbers in standard Morse code and can be received with pencil and paper. This system was used on OSCAR 6 and proved highly successful as a reliable means of obtaining real-time telemetry data.
An experimental Morse code message storage unit, Codestore, capable of storing and repeatedly retransmitting 18-word More& code messages loaded by ground stations in also aboard AMSAT-OSCAR 7. This unit was first flown on OSCAR 6.
The teletype telemetry encoder amplitude-modulates telemetry beacons on 29.50 MHz (200 mw), 145.98 MHz (200 mw) and frequency-shift keys the beacon on 435.10 MHz (300-400 mw), as selected by ground command. The Morse code telemetry encoder and Codestore message storage unit directly key these beacons as selected by ground command.
IS
YOUR ENVELOPE ON FILE?
Now that our club is handling three suffix letters for the W6 QSL Bureau, our sorters have found that some members have cards waiting for them at the bureau and no envelope on file! This irks the sorters, because it takes up needless file space and indicates lack of interest in receiving the cards promptly. We hope it is merely that they forgot to keep at least one envelope on file. The only acceptable size is 5 x 71 inches, and they are available from our QSL manager for 50 each. Contact George Williamson, K6YGN, at 1 2056. Send your Stamped, SelfAddressed Envelope ("SASE") to:
W6 QSL Bureau
2814 Empire Avenue
Burbank, California 91504
ONWARD AND UPWARD ...
We are pleased to offer congratulations to Ralph West, WB6YMF who has now joined the ranks of Advanced Class licensees, and to Steve Lambert from Cal Tech who is awaiting the good news about his Novice license which should be forthcoming shortly. Chas. Weir, W6UM, administered the exam to Steve.
75A1 RECEIVER DONATED TO AWB
Recently the club received the donation of a Collins 75A1 receivers Central Electronics Sideband Slicer (SSB adapter), speaker and manual, from benefactor Pat Barclay, WB6JJT. Jay Holladay, W6EJJ, received it in the name of the club and the board plans to put it to use in our novice position initially. Waldo Brown, W6QJO, who is the Station Facilities Chairman, is retubing and realigning it into tip top shape. To Pat, we all say Thanks!
ARRL MEMBERSHIP DUES
Sad news has come to the attention of your Treasurers Merrill Burnett, OCTOBER. ARRL dues will go up as of January 1, 1975, in the following manner:
Individual ARRL memberships made through the JPL Amateur Radio Club does not benefit the club member directly, but it is a revenue source for the radio club. In order for the club to get the benefit, ARRL memberships must be paid through the club; the club treasurer then pays the discounted amount to ARRL. No club revenue is derived from ARRL Life Memberships. You may, however, renew for more than one year at the old rate ($7.50/yr) by prepaying before January 1st. Send your money, membership number, and renewal date to M. P. Burnett, 201-225.
PUSH OR PULL?
We thought our club was doing well when we successfully traded in our old call, WA6DKJ, for a single-letter prefix, W6VIO. W6VIO, you will recall, belonged to a deceased club member, Jack Blindberry, and we petitioned for it under one of the FCC's rules. From the September issue of Cross Talk, the newsletter of the TRW Systems Group Amateur Radio Club, comes word that they successfully switched their call, WB6WPO, to ... steady, now . . . W6TRW. That's what I call an effective lobby! Congratulations, fellas. Now if only W6JPL were unassigned ...
ATTENTION, ARRL MEMBERS
By now you have received your Southwestern Division election ballots. Incumbent Director John Griggs, W6KW, has been declared elected for another 2-year term starting January 1, 1975, because he was the only eligible nominee, To him we offer our congratulations and best wishes. However, for the post of Vice Director there are three candidates:
Arnold Dahlman - W6UEI
Jay A. Holladay- W6EJJ
Clarence Mackay- K60PS
If you read the biographical information on the ballot, you will discover that W6EJJ is our own JPLARC trustee and director; as such, he is particularly close to all of us for letting him know our thoughts on League matters. He plans to be an active Vice Director, if elected, and to work closely to improve communications between the members and our Director. Because of these points, we heartily endorse Jay for this position, and hope you will also. But whomever your choice is, please show your interest in this election, and VOTE!
NASH WILLIAMS VICTIM OF HEART ATTACK
Nash Williams, W6HCD, was stricken with a mild heart attack while watching TV at home Sunday evening, September 30th Paramedics rushed him to Verdugo Hills Hospital where he has been recuperating. He came home October 16th, but his Doctor says no smoking and very limited visitors. Enforced rest and quiet is essential in the early stages of recovery. If you wish to see him, please call his XYL Billie first, to make a schedule, at 790-4387. Nash sends greetings and thanks to all club members for their well-wishes, and hopes to be able to return to work in a month if all goes well. Good luck, Nash.
THE ARC BOARD
Appointed Norm Chalfin (K6PGX) acting Vice President to fill out the term of W6ZGC who is recovering from a heart attack in Barstow. Best wishes to Helmut Mecke for a speedy recovery and lots of luck to Norm in his new job.
The Board also sanctioned the sale of Oscar 6 & 7 photo slides at the San Diego Convention being hold Nov 1, 2 and 3. They are $1.00 per net of 5 and will also be available at JPL ERC 114-104. Half of the profits go to JPL ARC and half to AMSAT.
APPOINTMENTS
ARC Member Dick Baugh was appointed JPL Energy Conversion Manager, Facilities and Construction Office.
Pete Lyman. WB6WXK was appointed Viking Project Spacecraft Performance and Flight Path Analysis Director, System Design and Integration Section.
Norm Chalfin K6PGX was appointed AMSAT Agent for Trademark and Patent Office Matters. He and Skip Reymann W6PAJ are AMSAT Life Members.
SAN DIEGO CONVENTION - NOVEMBER 1, 2 and 3
JPL ARC AND AMSAT will jointly man an OSCAR booth at the Convention on Nov let 2nd and 3rd. A continuous slide and tape show on Oscar will be presented and the Oscar slides will be an sale as mentioned above. In addition, it is planned to have a live Oscar station in operation to make contacts through Oscar 6 and 7. Help is needed to man the booth -one or two hours per shift would provide needed relief for the dedicated crew. Please contact Jay W6EJJ X-4443 or Norm K6PGX X-6833 If you plan to attend and can spare some time.
HAM FAMILY
Ex-President Maurice Piroumian, WAGOPB, has informed us that his 100% ham family now all sport permanent licenses. Pausing at Technician grade on their way to General class are:
XYL Jimmy WB6TPB
Daughter Linda WB6TTA
Son Robert WA6TPC
We expect to hear them frequently on the 2 meter repeaters.
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