SkyWire Frequently Asked Questions

This page contains answers to the most frequently asked questions about our SkyWire Serial Accessory.

  1. Will SkyWire work with my telescope?

    See the SkyWire page for a list of telescope models that have been tested and are known to work with SkyWire.

  2. What are the advantages and disadvantages of SkyWire vs. SkyFi?

    SkyWire is simpler to use than SkyFi - it plugs directly into your iPhone's dock connector on one end, and into your telescope's serial cable on the other. There are no wireless configuration issues to deal with, and no possible Wi-Fi interference issues. SkyWire is also less expensive - about half the cost of SkyFi.

    On the other hand, SkyWire isn't wireless - and as anyone who's tripped over a cable in the dark knows, that can be is a big disadvantage in the field. Since SkyWire plugs directly into your iOS device, you can't - for example - charge your phone while using SkyWire. SkyWire will drain your iPhone battery about 5%-10% faster than the iPhone alone. On the other hand, running the iPhone's Wi-Fi continuously (as with SkyFi) will also drain its battery somewhat faster than normal.

    In summary, we recommend:

    • SkyWire for users who want a simpler, more reliable, less expensive telescope control solution.

    • SkyFi for users who want to go wireless, don't mind dealing with Wi-Fi configuration issues, and generally prefer a more advanced solution.

  3. What do I need to use SkyWire?

    You need our SkySafari app, and an iPhone, iPad, or iPod Touch running iOS 4.0 or higher. SkyWire will not work with iOS 3.1.x or 3.2. SkyWire will not work with SkySafari Lite. As of January 2011, SkyWire is also not compatible with Orion's StarSeek iPhone apps (although that may change in the future).

    You need a computer-controllable telescope with a serial port, or a telescope control system with a serial port. Our SkySafari app talks to virtually every such system in existence - but check the SkySafari features page for a complete list.

    You'll also need serial cable that connects your telescope's serial port to a standard PC (9-pin male) serial port. Some telescope manufacturers supply such a serial cable with their scopes, or sell them as additional accessories. We sell serial cables for the most common telescope brands.

  4. I have an iPhone 5 or an iPad with the new, smaller Lightning connector. Can I still use SkyWire?

    Yes. SkyWire will work with Apple's Lightning-to-30-pin Adapter and Cable. SkyWire may also work with other third-party Lightning-to-30-pin adapters and cables, but we cannot guarantee that. Thus far we have only tested SkyWire with genuine Apple accessories.

    A Lightning version of SkyWire is currently under development, and we expect to offer it for sale in the second half of 2013.

  5. I have an Android device running SkySafari for Android. Can I use SkyWire to control my telescope?

    No. SkyWire was designed for, and is exclusively compatible with, iOS devices. For Android telescope connectivity options, see the SkySafari for Android Telescope Control and Frequently Asked Questions pages.

  6. I have a USB-only telescope controller (like iOptron, or Meade's LS series). Can I use a USB-to-serial adapter along with SkyWire to make it communicate with my telescope?

    No. Two reasons: first, the thin USB "A"-style connector found on the USB end of all USB-to-serial adapters won't physically fit into the smaller square USB "B"-style jack on the telescope (or its controller). Second, the driver software required to communicate with these telescopes is only available for Mac or PC operating systems - and SkyWire does not contain an embedded processor capable of running a full-blown operating system like Mac OS X, Windows, or Linux.

  7. The picture of SkyWire on your web site shows the sticker on the front. But on my SkyWire, the sticker is on the back!

    The sticker really is supposed to be on the back side of the connector. In the picture on our web site, we photoshopped the sticker onto the front side, so you can see what it looks like. Apologies for the confusion.

  8. When I plug SkyWire into my iPhone/iPad/iPod, I get a message that says "This accessory is not supported." What's wrong?

    Make sure your iPhone/iPad/iPod is running iOS 4 or higher. Make sure you have installed SkySafari version 2.1 or later. Make sure SkyWire is connected securely and snugly into your iPhone's dock connector. Try un-plugging and re-plugging it!

    If SkySafari is running as the active (foreground) app on your phone when you plug in SkyWire, SkySafari should display a message saying that "SkyWire has been successfully connected." You should see a similar message when you disconnect SkyWire.

    If neither of these things happen, but you're sure you're running iOS 4.x and SkySafari 2.1, there is a problem with your SkyWire unit. Contact us to obtain a replacement.

  9. OK, my SkyWire is working. But when I try to connect to the telescope, I get an error message!

    Most likely, you've connected SkyWire to the wrong port on your telescope. For the most common telescope brands, here's where the serial port is located:

    • Celestron - for all Celestron telescopes, the serial port is located on the bottom of the NexStar hand controller. Although Celestron sells a "PC Port" accessory that adds a second serial port to the mount base, SkySafari won't work with this. The mount base (with EQMOD) speaks an entirely different protocol than the NexStar hand controller, and the SynScan protocol is what SkySafari understands.

    • Orion/SkyWatcher - for these telescopes, the serial port is located on the bottom of the SynScan controller. There is an "EQMOD" accessory that adds a serial port to many Orion and SkyWatcher mounts. However, with the Celestron PC Port accessory, SkyWire won't work with this - the mount base speaks an entirely different protocol than the SynScan controller, which is what our app is designed to work with.

    • Meade - for all Meade ETX and LX-90 telescopes, the serial port is located on the bottom of the Autostar #497 controller. If you don't see a second telephone-style jack on the bottom of your Autostar, then you have the Autostar #494 or #495, not the #497. You'll need to order the Autostar #497 as an upgrade from Meade. For Meade LX-200 telescopes, the serial port is located on the mount base, and is labelled "RS-232". SkyWire will not work with the newer Meade LS models, which are USB-only, and lack a serial port.

    • iOptron and Vixen - as with the Meade LS telescopes, these mounts all lack a serial port. They cannot be used with SkyWire.

    • Others - consult your telescope manual. For Takahashi mounts, the serial port is a round connector on the mount base. For Sky Commander, Sky Tracker, ServoCAT, and Argo Navis systems, there are may be multiple connection possibilties, depending on how your equipment is configured, so read the manual. For "push-to" systems with encoders based on the Tangent Instruments BBox, like JMI's NGC-MAX or Dave Ek's "Ekbox", the serial port is located on the control box. It is not possible to plug the encoders directly into the iPhone or SkyWire - you need the control box!

    The second-most-likely possibility is that you've selected the wrong telescope type. Check your scope communication settings in SkySafari. Perhaps you've selected the Demo telescope type? If so, SkySafari will act as though it's connected to your telescope - but the scope won't move or track, since SkySafari isn't actually talking to anything.

    A third possibility: SkyWire is OK, but your telescope serial cable is defective. If you have a planetarium program like Voyager, Starry Night, or The Sky on your PC or Mac, try connecting to your telescope with that program using the same serial cable. All of our telescope serial cables are tested by the manufacturer, so it's very unlikely that this is the problem - but if all else fails, this is something to check.

  10. Fourth: it's possible that your telescope is not configured correctly. Some Celestron controllers won't respond to external commands until they've been star-aligned. The original Celestron NexStar 5/8 needs to be set to "RS-232 Mode" before it will communicate. Conversely, Orion/SkyWatcher SynScan controllers must not be in "PC-Direct" mode. On some telescope controllers (such as NGC-MAX, ServoCAT), the serial baud rate is configurable. SkySafari expects to communicate at 9600 baud, so make sure that's what your controller is using. If your telescope controller has upgradeable firmware, update to the latest version. Above all, read the manual - there's no subsitute for being familiar with your own equipment!

    If all else fails, contact us. It is possible that you've discovered a bug in our app, or uncovered an incompatibility with a particular telescope hardware or firmware version. We'll get it sorted out.

  11. SkySafari can communicate with my telescope using SkyWire, but it disconnects frequently. Or, it connects unreliably/intermittently; sometimes I get an error message saying "SkySafari can't make a wireless connection...", but I'm not using WiFi! What's going on?

    If SkySafari can't find the SkyWire attached to your iPhone, it will try to use WiFi for telescope communication - and of course that also fails, since you're not using WiFi. This error message indicates that the SkyWire is not firmly connected. Some iPhone/iPad cases prevent the connector from inserting all the way - if this is your problem, try using SkyWire without the case.

    It's also possible that dirt/grit/dust/lint has gotten into your iPhone connector, preventing good electrical contact. We've seen at least one very old, dirty iPhone 3G which could not connect to the same SkyWire that worke perfectly in a brand-new iPhone 4. The problem was clearly on the iPhone connector side. (Note that the SkyWire uses more pins than the standard iPhone USB connector, so it's more sensitive to this kind of problem.) Try cleaning out your iPhone connector with compressed air. If that fails, check for broken/bent pins inside the connector with a magnifying glass.

    Some iPhones/iPads seem to have trouble reconnecting to SkyWire after they have woken up from sleep. You can temporarily disable sleep while SkySafari is running. To do this, go to the Settings > Appearance screen, then turn the Prevent Auto-Lock switch ON.

    If you're sure you've got both a firm physical connection, and a clean iPhone/iPad dock connector, there may be something wrong with your SkyWire. If all else fails, contact us, and if you're within 30 days of your original purchase, we'll exchange your unit for another.

  12. I have an Orion StarSeek Telescope Control Cable, or a Redpark Serial Cable. Will it work with SkySafari on my iPhone/iPad/iPod Touch?

    No. The issue is firmware. Redpark's and Orion's cables identify themselves to iOS as different accessories than our app expects (com.southernstars.sw9a). Even though all of these cables are physically identical to SkyWire, this firmware difference is enough to prevent our app from recognizing the other cables.

    Due to Apple's restrictions, we cannot change our app to recognize Redpark's or Orion's cables; and Redpark cannot change its driver or SDK to recognize SkyWire. Apple's policy is very strict in this regard - each accessory is specifically designed for one app, and vice-versa. We cannot sell SkySafari on the iTunes store unless we adhere to Apple's rules!