ARISS switches to Ericsson radio after experiencing problems with the Kenwood D700

ISS Amateur Radio

After experiencing issues with the Kenwood D700 on two consecutive
school contacts, ARISS will use the Ericsson radio on the Columbus
module for ARISS contacts until problems with the D700 are resolved.

After experiencing issues with the Kenwood D700 on two consecutive
school contacts, ARISS will use the Ericsson radio on the Columbus
module for ARISS contacts until problems with the D700 are resolved.

According to Frank Bauer, KA3HDO, AMSAT's Vice President for Human
Spaceflight Programs, "...for some reason, our signals from the Service Module Kenwood D700 radio are much diminished. Our contact with Israel last Sunday had low audio levels, with good signals only near TCA.

"Our contact yesterday with the Hospital for Sick Children was even worse. Only one student was able to talk to Chris Hadfield before we lost the signal. The crew reports hearing the ground station well. Both these contacts were with our telebridge stations, some of the best out there. Also note that Chris Hadfield got on the IP Phone, immediately after the Hospital radio contact and answered all the student's questions, using that communications medium. So, while not optimal, we were able to make both these ARISS events successful

"After the Hospital contact, we had a full court press to revise uplinks and procedures to use the Ericsson radio that was recently installed in the Columbus Module instead of the D700. This was worked well into the crew sleep period, with the procedures ready for the crew at wakeup. While we had not fully checked out the radio, we felt the benefits of using this system outweighed the risks of using the D700, given its recent past performance. Our contact with the Japan school, using the Columbus Module Ericsson radio was very successful. We plan to use it on the contacts planned for next week."

ANS, ARISS

PY4MAB – Sun, 2013 – 02 – 10 16:49

TM-D700 Low audio on transmit issue

Re: TM-D700 Low audio issue

As a long time user of this excellent radio, when switching from APRS by turning off the integral TNC to use voice communications on both sides, I have found that occasionally weak audio on my transmit happens.

Suggestion - After the TNC is turned off, and new frequencies are selected, suggest the operator power off the radio, then turn on.
This power OFF/ON cycle resets this radio in the dual band or dual side mode, and FM Voice transmit level is usually restored.

Same thing happens if I try to use voice FM at the same time as an APRS packet is being automatically sent. Power ON/OFF cycle will reset the microphone audio level back to normal.

73 to all on the ISS and fan page
Pat KC6VVT