Astro Devices RJ22 Encoder Adapter Cable

Product Overview

The Astro Devices RJ22 Encoder Adapter Cable connects a rotary encoder to a digital setting circle (DSC) through a standard encoder cable. One end carries a 5-pin flat polarised connector that mates with US Digital S1, S2, S5 and S6 encoders as well as the CUI AMT102, while the other end terminates in an RJ22 (4P4C) jack. The assembly measures 100 mm (4") long and ships with a protective cap and a countersink M3 screw.

Who It's For

This cable suits push-to telescope builds that pair a US Digital (S1/S2/S5/S6) or CUI AMT102 encoder with a Nexus DSC or other RJ22-based digital setting circle. It is the interface piece between the encoder body and the RJ22 encoder cable running back to the DSC.

Key Features & Design

• Dual connector layout: a 5-pin flat polarised connector on one end and an RJ22 (4P4C) jack on the other.
• Encoder compatibility: mates with US Digital S1, S2, S5 and S6 encoders and the CUI AMT102.
• Compact length: 100 mm (4") keeps the run between encoder and cable short and tidy.
• Mounting hardware included: supplied with a cap and a countersink M3 screw.

Recommended Uses

Use this adapter to bring a US Digital or CUI encoder onto an RJ22 encoder cabling system, completing the signal path from the encoder to a digital setting circle on a Dobsonian or equatorial push-to setup.

Compatibility and Accessory Notes

The 5-pin flat polarised end fits US Digital S1, S2, S5 and S6 encoders and the CUI AMT102. The RJ22 (4P4C) jack accepts an encoder cable fitted with an RJ22 plug, which then carries the connection to the DSC. The included countersink M3 screw secures the adapter at the encoder.

Good to Know Before You Order

• Length: the cable is 100 mm (4"), intended as the short adapter link at the encoder rather than the full run to the DSC.
• Encoder cable needed separately: the RJ22 end connects to an RJ22-terminated encoder cable, which is what reaches the digital setting circle.
• In the box: one adapter encoder cable, a cap, and a countersink M3 screw.
• Weight: 30 g.

Frequently Asked Questions

Which encoders does it fit?

The 5-pin flat polarised connector is compatible with US Digital S1, S2, S5 and S6 encoders and the CUI AMT102.

What connects to the RJ22 end?

An encoder cable fitted with an RJ22 (4P4C) plug, which runs from this adapter back to the digital setting circle.

How long is the cable?

It is 100 mm (4") long.

Is it difficult to set up?

No. The flat polarised connector keys to the encoder in one orientation and the RJ22 jack plugs into the encoder cable, so the connections are direct and self-aligning. The included M3 countersink screw holds it in place.

What comes in the box?

One adapter encoder cable, along with a cap and a countersink M3 screw.

Bottom Line

The Astro Devices RJ22 Encoder Adapter Cable is the short, purpose-made link between a US Digital or CUI encoder and an RJ22 encoder cable, letting the encoder feed its position data to a digital setting circle with a clean, keyed connection.