Astro Devices SkyWatcher StarGate 18/20 Encoder Kit

Product Overview

Digital setting circles can only tell you where your telescope is pointed when encoders are fitted to its axes. This kit supplies those encoders, built specifically for the SkyWatcher StarGate 18" and 20" Dobsonians. The two encoders attach to the altitude and azimuth axes and send position signals to a digital setting circle unit such as a Nexus DSC, which then reads out coordinates and guides you to any target in its database. The altitude encoder resolves 815,000 steps and the azimuth encoder 655,360 steps, so pointing stays fine-grained across the full sky.

Who It's For

This kit is for owners of a non-GOTO SkyWatcher StarGate 18" or 20" Dobsonian who want to add push-to guidance. It pairs with a separately purchased digital setting circle computer and turns manual slewing into a directed hunt for faint objects.

Key Features & Design

• Two matched encoders: one for altitude, one for azimuth, sized and shaped for the StarGate's axes.
• High resolution: 815,000 steps on altitude and 655,360 steps on azimuth for accurate position reporting.
• Model-specific hardware: the included installation hardware set is made for the StarGate 18"/20" mechanics rather than adapted from a generic kit.
• Custom-length cable: the encoder cable is cut to the length your setup needs.
• Complete package: encoders, hardware, cable, and an installation instruction booklet arrive together.

Encoders and Electronics

Each encoder converts axis rotation into a stream of electrical steps that the digital setting circle counts to track position. The higher the step count, the finer the resolution, and this kit's 815,000-step altitude and 655,360-step azimuth encoders give the DSC enough detail to place high-magnification eyepiece fields on target. A single encoder cable carries both signals back to the DSC unit.

Recommended Uses

The kit suits visual observers who star-hop across crowded fields and want a faster route to galaxies, clusters, and nebulae. Combined with a digital setting circle, it lets you dial in an object and walk the scope to it, which is especially useful under light-polluted skies where faint targets are hard to find by eye.

Compatibility and Accessory Notes

This kit fits non-GOTO StarGate telescopes sold outside the USA. Compatible units have the rocker box riding on three teflon posts installed in the ground board. Units that use a mix of metal and plastic balls between the ground board and the rocker box (acting like a ball bearing) are a different design and are not compatible. The encoders feed a digital setting circle computer such as a Nexus DSC, which is sold separately.

Good to Know Before You Order

• Cable length is made to order: after your order, Astro Devices contacts you to confirm the encoder cable length your telescope needs.
• Check the rocker box design: the three-teflon-post version is the compatible one; the ball-bearing style is not.
• DSC computer sold separately: the kit provides the encoders and cable, not the digital setting circle unit itself.
• Shipping weight: the kit weighs about 600 g.

Frequently Asked Questions

Is it difficult to set up?

The encoders mount to the altitude and azimuth axes with the supplied hardware, and the single cable connects them to your DSC. An installation instruction booklet is included to walk through each step for the StarGate.

Which digital setting circle does it work with?

The encoders output standard step signals for a DSC computer such as a Nexus DSC, which is purchased separately.

How do I know my StarGate is compatible?

Look at the rocker box: if it rides on three teflon posts in the ground board, the kit fits. If there are metal and plastic balls acting as a bearing, it does not.

What resolution do the encoders provide?

The altitude encoder resolves 815,000 steps and the azimuth encoder 655,360 steps.

Is the DSC computer included?

No. The kit contains the two encoders, installation hardware, an encoder cable, and an instruction booklet.

Bottom Line

The StarGate 18/20 Encoder Kit gives your SkyWatcher StarGate the altitude and azimuth encoders it needs to work with digital setting circles. With model-specific hardware, high-resolution encoders, and a made-to-length cable, it is a direct route to push-to observing on the big StarGate Dobsonians.