SakhaCube-Cholbon (RS18S) Transmissions

[thepetrovich]

April 10 — 14, 2026: SSTV Image Transmission Planned from SAKHACUBE-CHOLBON (RS18S) CubeSat

From April 10 (12:00 UTC) to April 14 (11:59 UTC), 2026, SAKHACUBE-CHOLBON (RS18S) CubeSat will be transmitting images via SSTV mode. The event commemorates the International Day of Human Space Flight on April 12.

Event Schedule:

• Active Broadcasting: 2026-04-10 12:00 UTC — 2026-04-11 11:59 UTC

• Maintenance: 2026-04-11 12:00 UTC — 2026-04-11 23:59 UTC

• Active Broadcasting: 2026-04-12 00:00 UTC — 2026-04-12 23:59 UTC

• Maintenance: 2026-04-13 00:00 UTC — 2026-04-13 11:59 UTC

• Active Broadcasting: 2026-04-13 12:00 UTC — 2026-04-14 11:59 UTC

Interval between image transmissions is 180 seconds, Robot36 mode. The schedule may be adjusted depending on the satellite performance (energy balance, transceiver temperature, etc.).

Details on SAKHACUBE-CHOLBON (RS18S) satellite:

• Frequency: 437.350 MHz

• Modes: GMSK 2k4 USP FEC, GMSK 9k6 USP FEC, SSTV Robot36

• Callsign: RS18S

• NORAD SATCAT ID: 67290

• SatNOGS / sonik.space ID: CPWN-2484-4785-1722-0154

• IARU Coordination completed on August 25, 2025

QSL Cards: To confirm reception and request a QSL card, please send your reports to amsat@yksa.space. Please follow the provided submission format.

Email Subject: SAKHACUBE-CHOLBON 10-14 APR SSTV QSL Request (Your Callsign or Full Name)

Report Form:

1. Full Name and Callsign (if applicable)

2. Time of Reception (UTC)

3. Location (QTH or City/Country)

4. Mode (SSTV/Telemetry) and optional details on the rig and software

5. Decoded images (as attachments)

6. Preferred QSL Card Language (Russian or English)

7. Paper Card Request: Indicate if you wish to receive a paper QSL card (available for those who have received 2 or more unique images).

8. Mailing Address: Required only if a paper QSL card is requested.

[pu4elt]

• 2026-04-11 01:32UTC
  
  
• 2026-04-11 01:34UTC
  
  
• SakhaCube-Cholbon (RS18S) over Brazil !!

[DD7MB_Max]

2026-04-10 21:03:37 over germany

[dl7ndr]

2026-04-10 21:05

2026-04-10 21:08

[dl7ndr]

@thepetrovich

Email Subject: SAKHACUBE-CHOLBON 10-14 APR SSTV QSL Request

Do you know when the cards for 07-09 MAR SSTV will be sent out?

By the way, do you also plan to activate the “mailbox-mode message relay service”?

Daniel

[thepetrovich]

Hi, most of the eQSL cards were sent out on Apr.2, some cards are delayed due to email issues. We will try to send the rest soon. As for the paper cards, unfortunately I cannot give a certain date, the logistics in Yakutsk is a bit complicated. We are still planning to mail them, so stay tuned!

Mailbox-mode (or “store-and-forward”) message relay is in development. We have had issues with the onboard UHF transceiver which severely impact the uplink budget (in other words, the spacecraft is “deaf”), so we are not sure how to proceed. In any case, custom software and modems are necessary, as we are using SPUTNIX’s implementation of AX.25/G3RUH; we will publish everything in advance.

[dl7ndr]

2026-04-11 10:02

2026-04-11 10:04

2026-04-11 10:06

2026-04-11 10:09

[dl7ndr]

2026-04-12 11:18

[PY4ZBZ]

[dvdiyen]

[N6RFM]

RX this AM over Bristol, RI.

[2e0gkw]

A few recorded while away over the weekend.

11-Apr-26 1138UTC

11-Apr-26 1140UTC

12-Apr-26 1115UTC

12-Apr-26 1117UTC

[2e0gkw]

2 images heard during 1029+UTC over SE London but no / very poor decode. Should spend more time visiting my sister in NW England - seem to get much better / clearer signals there