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SARCTRAC Mk2

SARCNET
Published by Julie & Joe in SARCTRAC Mk2 · 1 November 2020
SARCTRAC Mk2, our second generation Satellite Antenna Rotator Controller and TRACker, was released in October 2020. This forum is about setting up and operating SARCTRAC for portable operation, including:
  • How to modify your tripod and mount SARCTRAC on it
  • How to build your own lift-arm and mount your antenna to it
  • How to mount the SARCTRAC 3D Sensor on your antenna
  • How to set up your radios to work with SARCTRAC
  • How to get started in tracking and operating satellites
  • What radios you use and what satellites you have worked with SARCTRAC
We hope you have a lot of fun with it and we are here to support you. 73, Julie VK3FOWL and Joe VK3YSP.



13
reviews

shaun ei8hcb
06 Dec 2020
this works out of the box well worth getting i was messing about with it i corrupted file my fault I Am sure but support was spot on it would be nice to have ic 7900 ans ic 705 supported thanks joe
Julie and Joe
06 Dec 2020
Hi Shaun,
You expertly demonstrated that it was easy to restore a SARCTRAC backup to fix a corrupted file. Well done!
SARCTRAC uses the latest version of the Hamlib Radio Control Library.
At the moment Hamlib does not support the Icom IC-7900, nor the Icom IC-705, which are relatively new models.
We expect they will be supported in Hamlib version 4.0, but we are not sure when it will be released.
The good news is that SARCTRAC is fully field-upgradable including its libraries and even the operating system.
So it should be no problem to install when Hamlib version 4.0 is released and we have tested it.
Happy tracking and keep in touch.
Kind regards and stay safe,
Julie and Joe
Daryl Hooke
28 Dec 2020
G’day, I’m itching to get my hands on MK2. I have had my first taste of FM satellite ops over the Christmas break and quickly discovered operating a beam hand held is not for me.
Cheers All de VK3AWA
Julie and Joe
28 Dec 2020
Hi Daryl,

Well done on your first satellite QSO! Working FM satellites is easy, especially if you have programmed in 3 Doppler Frequencies (+5kHz, 0kHz and -5kHz) into your VHF/UHF handheld and change channels at the start, middle and end of a pass. Using two handhelds, one for the up-link and one for the down-link is better, as you can hear your own signal from the satellite. If you rig up a PTT headset, you can simplify the audio interface. Pointing a Yagi antenna is not too difficult, either, if you study the satellite pass and have a good sense of direction. And, once you have received a signal, it is easy to peak up the Yagi direction. SSB satellites are a little more difficult, as you have to constantly adjust the frequency, but they are a very rewarding source of contacts. It is good to get some experience, manually tracking satellites, because you learn a lot about the process.

The main reason we developed SARCTRAC was that it was hard for little kids to hold the antenna and point it in the right direction for any length of time. Our original Arduino tracker was an improvement, but it took so much stuff and so long to set it up we often missed a pass. SARCTRAC just works and lets us concentrate on making contacts. We like working from parks and summits. A satellite contact, while portable, is a real buzz. It is now as easy as setting up our tripod, attaching the antenna, connecting SARCTRAC and an FT-817 to a battery and waiting for a pass.
...
Pablo Lewin
19 Apr 2021
Hi Julie and Joe, well I got the mount, followed the instructions and..PRESTO!! AMAZING! Today was the second day I was playing with it, receiving satellites I never even knew existed. So far no FM birds flying over me but with my FT-817 I'm sure the QSOs are coming. Two question a few times when receiving the asterisk birds the receive/transmit will cycle back and forth, is that normal? Also I'd like to work the digital birds, so if I connect the CAT cable to the computer instead of the mount, is there a way to setup this system for digital transmission on the ssb digital birds?. Thanks again! QRV de Pablo Lewin WA6RSV (YouTube video coming soon).
Julie and Joe
19 Apr 2021
Hi Pablo,
Thanks for the kind words. It is nice to get feedback. The FT-817 has two VFOs, for TX and RX, and it must be set into split mode. For the FT-817, SARCTRAC must switch TX/RX VFOs on a programmed basis, say 1 TX to 4 RX. Unfortunately the FT-817 exhibits all the radio control anomalies identified here: https://www.sarcnet.org/sarctrac.html#RadioControl. That means that when it switches to the TX VFO to program it the uplink frequency is heard, momentarily. This is probably what you are describing. Some radios can do the TX VFO programming in the background. This is all determined by HAMLIB. For digital modes you need to interface audio tones and PTT to the rig, not the rotator. For the FT-817 there are choices to be made using either the ACC or DATA connectors for this. Bear in mind the 1Hz Doppler correction rate together with the above radio control anomalies would not support digital modes e.g. APRS/FT8 via an SSB transceiver, if that is what you were thinking.
Hope that helps
73, Julie and Joe.
Frank
25 Apr 2021
Hi Julie and Joe,
I'm still reading all the information you send to prepair myself for the installation of the Sarctrak mk2.
I was wondering if its possible to use bluetooth for the CAT connection.
I have this working with the hamradio software on a raspberry, and this works great.
73, Frank PA3EMT
Julie and Joe
25 Apr 2021
Hi Frank,
Bluetooth is not a CAT option in this case. We tried running several types of serial Bluetooth adapters with the built-in RPi Bluetooth driver and none worked. Also, SARCTRAC was designed for portable, attended operation, not permanent installation with remoted or unattended operation. Operating SARCTRAC in this way would be unsafe and may cause damage or injury.
73, Julie and Joe
Steven Holt
25 Apr 2021
I just found this product while scanning the web. This looks great. A couple of questions. I have a Yeasu FT 817 and A Yaesu FT 818 I want to use one for xmit and 1 for Rx connecting via the the Ct62 cables. Where do they connect to the controller? do you offer repair parts should I somehow break something? Do I need to have internet/ Cell connection to make this work? thanks for the help.
Steven
Julie and Joe
26 Apr 2021
Hi Steven,
SARCTRAC has two USB ports. The FT-817 would be connected to one port and configured as a receiver, while the FT-818 would be connected to the other port and configured as a transmitter. You need a CT-62 CAT cable for each. Yes, we have plenty of parts. You need a home WiFi router / access point, or a mobile device personal hotspot, with Internet access. SARCTRAC only needs the Internet to download new orbital element libraries, occasionally, but it is controlled from any web browser over the WiFi network. It was designed for portable operation.
73, Julie and Joe
Richard Bunn
23 May 2021
I am interested in your rotor system, but the website says out of stock. I am volunteering with the local CAP squadron as a STEM / communications senior. Your system looks like a perfect way to demonstrate Amateur Satellite operations. Let me know when you have more units manufactured. I will use either the FT736R or the IC9700.

73 Rick Bunn / N4ASX
Julie and Joe
23 May 2021
Hi Rick,
We have completed our production run of 50 SARCTRAC Mk2 units for 2021. They sold out in less than two months! Selling rotators, of course, is not our core mission. We don't think we will do any more this year, but we will let everyone know if we do. HAMLIB 3.3 has been upgraded to HAMLIB 4.1, which may support the radios you have. We expect to be working on a software upgrade for that, before the next production.
73, Julie and Joe.
Cliff ZL1CTS
31 May 2021
Hi All, received my rotator a week or so ago, Rotator works very well, have been testing and it picks up GPS just fine and can track well. Looking forward to IC9700 support being included in a future update as this will save me taking a computer with gpradict/hamlib to do the doppler tracking!! The limited time I have to use radio means I seem to miss all the good passes, so yet to make a contact, but will soon no doubt

thanks for great bit of kit

Cheers

Cliff ZL1CTS
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