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AO-40 QRV report on orbit#238 from Japan.



Hello This is Yoshi.

  Sorry for delayed report. This is the report of AO-40 QRV on orbit#238
during 14:45-21:50z of May-7th.2001.

1. Equipments.

  This time, I used two system for receiving S2 band.

  1) For continuos receiving S2-MB. MAKI-Electronics 29ele LOOP YAGI(21dBi)
     and LNA (NF 0.3dB. made by JI5MFZ), Basic modified Drake2880, FT-817
     and AO40RCV. FT-817 can be controlled from AO40RCV.
  2) For communication, TDK 45cm Dish for BS sat. I modified it with 2.5turn
     helix feed for 2.4GHz use. Drake2880 (FET repaird with MiniCircuit
     ERA-3) and IC-821. This system ability was about 6-8dB less than the
     1) system.... :-(
  3) For U-Uplink. IC-821 (20w) and 6ele YAGI for FM sat (10dBi). Elevation
     was fixed at 25 degrees.

2. QRV documents.

  14:45z  Returned home and started receiving S2-MB.
  14:57z  Found Xpond on at telemetry data.
  15:09z  Looptest-OK at 2401.400 (Uplink 435.596 with 20W). RST 419
          then started to send "VVV DE JF6BCC"
  15:11z  Worked with JA0BBW by 20W (His419-My579!). My signal can be
          heard a little bit weak than his, so my receiving ability will
          not be enough... :-(
  15:17z  Worked with JA1BLC by 20W (419-559).
  15:20z  Started CQ on 2401.400.
  15:28z  Worked with JH1NPQ by 15W (419-559).
  15:30z  Stopped CQ and started serching the downlink band.
  15:33z  Heard something SSB on 2401.347 but could not copy.
  15:36z  Found CW CQ of JK1DVX on 2401.347.
  15:38z  Called and worked with JK1DVX by 15W (419-569).
  15:41z  Heard JA6BX calling somebody on that freq. Then he started QSO
          with JK1DVX.
  15:45z  Started CQ on 2401.350 (uplink 435.642).
  15:48z  Worked with JA6BX by 15W (519-539).
  15:56z  Heard VK? somebody talking with ZL1AOX by SSB, but I could not
          copy his callsign. I could not hear any signal from ZL1AOX.
  16:00z  QRT. Left the S2-MB receiving system running and went to bed.
          The local time was 1:00am!
  17:00z  had waked up by bell-clock! :-(  Checked and adjust the direction
          of antenna and frequency.
  18:00z  had waked up again.
  19:39z  had waked up. AO40RCV was unlocked so adjust again. Tried to
          loop on 2401.400 but was very weak.
  20:50z  Waked up. Too sleepy.... :-(  Checked and adjusted the direction
          of antenna and frequency. S2-Mb became strong!
  21:00z  Heard SSB CQ of JA4GVA on 2401.373. I tried to loop buy my signal
          was too weak to talk with him on SSB! I checked the telemetry
          and found the AGG was over 12dB!
  21:08z  Heard CW CQ of JM1KVW.
  21:10z  Found a FM modulated signal on 2401.398. It might be came from
          illegal commercial station on 435MHz around asia... Is it the
          reason of high AGC value?
  21:12z  Heard CW signal of JH1QKG.
  21:14z  Heard sombodys SSB signal but could not copy callsign.
  21:18z  Started CQ on 2401.415 by CW. My output power was 20W, but the
          sat was at elv.55 degrees. My antenna is elv.25 degrees fixed
          so the antenna gain will be -6dB than the front. My signal was
          RST 519.
  21:22z  Called and worked with JA4BLC (519-559). His signal was as same
          strong as mine so my receiving ability is so poor!
  21:30z  QRT for prepairing my work. It was 6:30 local time.
  21:45z  Found a FM modulated signal at the S2-MB frequency. It might be
          from asian illegal operation... sigh...
  21:50z  Stop receiving S2-MB.

3. AGC value chart from telemetry data.

  I tried to make a chart of AGC value during the transponder operatiom.
I used latest archive data of VP9MU and P3T.

  U-Rx AGC
  http://plaza16.mbn.or.jp/~palau/images/ao40-orb238-uagc.gif

  The peak of U-AGC at around MA=151 was +19.7dB (16:07z). Maybe when
this time, somebody made too much high-power uplink.

  During my QRV. the avarage of U-AGC was;
    15:09z-1530z    4.7dB
    15:31z-15:45z   5.0dB
    15:45z-16:00z   3.6dB
      :
    20:50z-21:30z  11.5dB

  L1-Rx AGC
  http://plaza16.mbn.or.jp/~palau/images/ao40-orb238-l1agc.gif

  Look! how calm on L uplink!. We should prepare L uplink system for AO-40
ASAP.

- ... -

  This time, I used two system for receive S2-MB and communication at same
time, but my second system was not so good. Then, I decided to make IF
splitting cable as below.

                                         +--------> IC-821 for comm.
                                         |
  29ele LOOP ---[LNA}-[2880}---------[Splitter] *1
                              (2m IF)    |
                                         +--------> FT-817 for MB decode.
                                                      ||
                                                   AO40RCV

    *1 : MASPRO 2SPF-CS (junk $8.00). 2way splitter for BS/CS sat. cable.
         Insretion loss is 4dB on 145MHz by their data sheet. I checked
         it, and this splitter reduced 2 S unit reading of IC-821. 3dB is
         splitting deduction so the loss will be 1-3dB.

  My next chance is tomorrow moring! I will try again by this.

  73 de Yoshi.


Yoshihiro Imaishi JF6BCC/KH2GR
GL:PM53JV, ex KC6IY(T88IY),V63BP
mailto:jf6bcc@jarl.com or jf6bcc@jamsat.or.jp
<http://plaza16.mbn.or.jp/~palau/> Sorry, Japanese only now.
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