Appendix – Hardware and Software History


The Synta/Skywatcher/Orion Series of Equatorial Mounts have been around a considerable period of time. In an effort to capture a little of the history
I have created this potted history from web research. Dates where unknown are stated as such. Information was gleaned from Syntas own history
and various web research.

As far as I know, dates given are accurate but there may be discrepancies especially between country release dates for earlier mounts.

2-Release Dates and Versions of Mount Hardware

Below is a potted history of the EQ6 and the HEQ5. You should note that due to the long supply chains and local stock situations some older mounts
were being shipped at various times and also some versions appear slightly different even from the factory.
The most easily visible differences in the mounts are the polar scope illuminators. No two mounts ever seem to be the same with some having very bright
LEDs and some having very dim ones. Some of the earlier versions have a dimmer control (EQ6 Only) set into the side panel.

Mounts manufactured after 2008 are, based on my own experience, better in many respects. The overall Quality Control (QC) seems better. Older
mounts were often loaded with a dreadful lubricant. Even later mounts may suffer under lubrication and poor overall tuning. All mounts can be improved by
careful tuning and older ones improved by cleaning out the factory lubricants and replacing them with a modern lubricant such as TF2 or Superlube.

The EQ6/NEQ6 and HEQ5 broadly comprise of three main units; The motors; the motor control board and the handset (the HEQ5 has two internal boards
one for the motors control and one for the power input the two boards are identical in function to the single board in the EQ6).
All of these are replaceable. The GoTo and Syntrek versions are identical as far as the mount hardware goes the only difference being the hand controller
while the non-GoTo versions use different motors and motor control boards. These are removed and replaced during a GoTo upgrade.

Early version mounts up to Early 2006 were shipped with version 1 or 2 handsets. These are non-software upgradeable.

2001 (Spring) The first version of EQ6 Released. Tracking motors only. The Rated payload for the EQ6 is 25kg.
2001 (Fall) The first version of HEQ5 released. Tracking motors only. The Rated payload for the HEQ5 is 15kg.
2004 The first version of Synscan released. Version 1 and 2 handsets are non-upgradeable.
Early 2006 First version 3 handsets start to ship with GoTo (Pro) models. These feature flash upgrade options. A full listing of software updates is given below.
Dates unknown Across the mounts development period some mounts feature slightly different features. Users had complained that early mounts had too bright an LED in the polar scope. Some mounts were supplied with a very reduced power LED while some other mounts feature a small rotary control that allows for variable LED power/dimming.
Date Unknown Syntrek versions appear. These have the same mount internals as the GoTo (Pro) version mounts but are not supplied with the GoTo handset. The GoTo functionality can be supplied via PC with third-party add-ons. The Syntrek version may have only become available in 2008 with the rollout of Synscan Version 3.21 which allowed support for external serial commands to the Motor Control Board.
2008 (May) First NEQ6 versions of the EQ6 start to appear. These are initially supplied ONLY with the 300P telescope tube. The first versions feature only an extended weight bar to help balance the 300P tube. Internals are identical to EQ6 versions. No data on Motor Board and some NEQ6s reported having Version 1 MCBs (this is not validated).
2009 Some mounts appear using an upgraded Motor Control Board (version 2). Version 2 Motor Control Boards allow for software dimming of the polar scope LED via the GoTo handset which combined with version 3.27 Software.
2010/2011 NEQ6 Mounts start to appear sold as EQ6s. Most have just the extended weight bar, a few start to appear with dual saddle plates which can be swapped out between a Vixen and a Losmandy Plate – this is a physical changeover rather than a dual plate and requires the user to remove the plate from the mount and replace it with the alternate plate.
Various Across this period NEQ6 and EQ6 are often identical in everything but nameplate although the NEQ6 always ships with a longer weight bar. All internals are identical. Some mounts ship with just a Vixen saddle, some with the kit which allows the saddles to be swapped, and others with dual saddle plates which can accommodate either dovetail style.
Mid 2011 All EQ6 Shipments are now of the NEQ6 version. This version features a single saddle plate that can accommodate either a Vixen or a Losmandy dovetail. All other specifications identical to later EQ6s.
Dec 2012 EQ6 Alt Az First Shipments almost 1 year after being announced. Alt Az Mount features encoders, locking power plug (Country dependent), and a belt drive. Synscan software is upgraded to accommodate features in Alt/Az version (Version 3.32)
April 2014 V4 Handset starts to ship to replace the older V3 handset. See software release notes below for full details of the changes.
HEQ5 Alongside HEQ6
An EQ6 / NEQ6 Pro alongside my own modified HEQ5. Pro versions with GoTo are mostly white while the non-GoTo versions are most usually black. Weights for the mount head are given. Note: This applies only to European versions. American versions with the Orion Brand are often black even when GoTo equipped. Both mounts above are equipped with Astro Developments Alt/Az Bolts.
3-Synscan Software Releases (most recent first)

Version 4.36.02 Release Date 13th November, 2014

Update to release version of V4 Hand controller. See the article below for details on the differences
between V4 hand controller and V3 hand controller

New Features:

1. User configurable declination offset for a mount(e.g. EQ8) which supports Auto-Home function.

2. Astronomical time-lapse photography.

3. Atmospheric refraction, cone error and non-perpendicular error compensations for better pointing accuracy.
Cone error measured in 3-Star alignment can be used in subsequent 1-Star or 2-Star alignment.

4. Meridian flipping for GOTO can be enforced or disabled.

5. New algorithm for alignment stars filtering to improve alignment quality.

Bugs fixed:
1. Occasional irregular approaching at the end of GOTO.
2. New firmware uses J.2000 coordinates for computer communication.
3. Unreliable Auto-Home when the mount is already at home position.
4. Fix bug in time zone setting.
5. Fix Astro Time-Lapse bug in v4.36.01 firmware and other minor bugs.

Synscan Version 4 Handset versus Previous Version 3 Hand Conroller/Paddle
(Dateline January 2015)As of April 2014 the original V3 handset was replaced with the V4 handset. Some mounts shipped after April 2014 may containthe V3 handset but all newly manufactured units will contain the V4 handset.

The handset has a slightly different appearance as can be seen below from the two line drawings. The change was required as
components used in the original V3 handset were no longer available forcing a redesign.

Functionality is more or less identical. Key changes are detailed below.


  1. Unlike the V3 handset, the V4 has no DC power input socket so it cannot be powered stand alone from the mount.
    It must be connected to a mount that has power in order to operate.
  2. The V3 and V4 hand controllers are interoperable on any Skywatcher/Orion GoTo system that uses the GoTo hand controller.
  3. The V4 hand controller is NOT firmware compatible with the V3 hand controller. Skywatcher will provide firmware
    updates for BOTH V3 AND V4 hand controllers in the future as the requirements for upgrades arise.
  4. There is no need for existing V3 users to consider V4 as an upgrade. Functionality is not upgraded
    (although there are some slight differences between the two hand controllers). However any users with
    a broken/damaged V3 hand controller will have no choice but to move to a V4 hand controller as the
    V3 hand controller is now no longer available.
  5. Separate manuals/user guides are available for each hand controller from the Skywatcher site.

Version 3.36 Release Date 11th July 2014

New Features:

1. User-configurable declination offset for a mount (e.g. EQ8) which supports Auto-Home function.

2. Astronomical time-lapse photography.

3. Atmospheric refraction, cone error and non-perpendicular error compensations for better pointing accuracy.
Cone error measured in 3-Star alignment can be used in subsequent 1-Star or 2-Star alignment.

4. Meridian flipping for GOTO can be enforced or disabled.

5. New algorithm for alignment stars filtering to improve alignment quality.

Bugs fixed:
1. Occasional irregular approaching at the end of GOTO.
2. New firmware uses J.2000 coordinates for computer communication.
3. Unreliable Auto-Home when the mount is already at home position.
4. Other minor bugs.

Version 3.35 Release Date 24th April, 2013

1. Implemented an all-new polar alignment algorithm.
The Latitude adjustment and the Azimuth adjustment have been split into two steps.2. New adjustment allow users to set the maximum altitude for a GoTo slewing on equatorial mount.3. Some bugs were fixedincluding:
PAE inaccuracy in some regions of the sky, frozen of directional buttons after starting from a parked position
and incorrect tracking speed after GoTo at the Moon.

Version 3.34 Release Date 13th February 2013

1. Update from previous firmware of SynScan Ver.03.32.

2. Fix the bug in connecting SynScan GPS at power-up and enhance the reliability.

3. In EQ Mode operation, recover displaying the Hour Angle of Polaris to providing assistant information for polar alignment.

The Hour Angle of Polaris can be viewed at the beginning after the location and time settings or can be browsed
at the “Utility\Show Information\Polaris Pos” sub-menu. Under the sub-menu, Polaris Pos., press the scroll keys to
switch viewing between the Polaris position in polarscope and the hour angle of Polaris.

4. Add editing of the interval time setting between exposures in the Configuration of Camera Control function in Utility.

Users may change and set the time interval between exposures from 1 second to 10 minutes or more.

5. Temporarily disable the polar (re-)alignment function for the feature still under improvement.

Version 3.32 Release Date 12th December 2012

The final version of 3.28 with all star polar alignment routine and software features to accommodate the EQ6 Alt/Az version and the proposed EQ8 mount.

Version 3.28 BETA – Release Date circa 31st March 2012

BETA TEST VERSION OF 3.28 NOT the official SynScan EQ official firmware release.
A new feature of Polar Re-alignment is added under the Alignment sub-menu of the hand control in the firmware.This is an ‘any star’ polar alignment routine.

Version 3.27 – Release Date 6th January 2010

1. Fix the bug in the SAO catalog regarding disabling the key- pressed slewing
Problem: Unable to drive and slew the telescope with the directional keys after browsing the SAO catalog.
Result: The directional keys are properly activated after browsing the SAO catalog.2. Fix the bug in the User Object coordinate editing.
Problem: In the User Object function, under RA-Dec format, when the user enters an object with a declination angle between 0 and -1 degree the
value becomes positive after the coordinates are saved. This causes GoTo pointing inaccuracy.
Result: The user-entered coordinates are saved properly.3. Fix the error in the database of NGC, IC catalogs.
Problem: In the NGC and IC catalogs, the coordinates of the objects located between 0 and -1 degree in declination always read as positive.
This causes GoTo pointing inaccuracy.
Result: The coordinates are read as their true values.

3.27 also supports a polar scope dimming feature from the UTILITIES menus of the handset if the mounts
Motor Control Board is version 2 or above.
** This was not in the Synscan documentation.

Version 3.25 – Release Date 24th June 2009

1. Fix the bug that existed in the Time Zone Setting
Problem: Unable to save the data entered by using the scroll-down key.
Result: Now the user is able to enter the data by pressing either the scroll-down and scroll-up key.

2. Fix the bug that existed in the PAE Function
Problem: Incorrect data calculation occurred when the RA axis of the telescope (AX2) was pointed at a negative angle.
Solution: Now the PAE functions properly when the RA axis (AZ2) is pointed at a negative angle.

Version 3.24 – Release Date 26th January 2009

1). Fix bugs in firmware version 3.23
Now the hand control setting will remain upon power-up, after the PAE function was performed.

2). Improve LED and LCD backlight performance.

Version 3.23 – Release Date 30th July, 2008

1. Fix bugs that existed in firmware version 3.22
Now tracking mode is deactivated automatically when the goto object selected is a user-defined alt-azimuth position.

2. Fix bugs that existed in firmware version 3.22
Now the hand control will not lock up when the user chooses to advance directly to the Show Position option, skipping the initial alignment procedure.

Version 3.22 – Release Date 5th June 2008

1. Add SAO submenu in Object Catalog.
The total number of objects in the database increased to 42,900.

2. Enhance Show Position Function: display telescope current position by RA/Dec, AZ/ALT or motor drive readings of both axes.
The data display is accurate to one arc seconds.

3. Add precession compensation in coordinates calculation.

4. Additional information such as the rise, transit and set time of an object is available when browsing the information for an object.
If a selected catalog object is currently below the horizon, the hand control will prompt “Below horizon!” for two seconds to notify the user.

5. Improve the “PC Direct Mode” function and fix the directional key lock-out problem in “PC Direct Mode”.

Version 3.21 – Release Date 4th January 2008

1. Smoother response to manual guiding and PC-based auto guiding command.

2. “PC Direct Mode” added.
It allows the PC to communicate directly with the motor controller via RS-232C connection.
The RS-232C port of the PC should be configured as 9600bps, 1 start bit, 8 data bits, 1 stop bit, no parity check and no flow control.
Activate “PC Direct Mode” under “Utility\PC Direct Mode>”.
Press the “ESC” key to exit. The 4 direction buttons and rate-controlling function operate as usual under this mode.
This feature is also designed for future applications.

Version 3.20 – Release Date 16th November 2007

Improved the planet orbital calculation and fixed the inconsistent Double Star and Variable Star Catalogs.

1. The time zone setting has been changed to more precise in minutes for locations with half hour definition.
For example, if you live in a region with -3.5 hours of time zone, the setting will be -03:30, indicating minus three hour and thirty minutes.

2. The planets’ orbital calculations have been enhanced
based on “Keplerian Elements for Approximate Positions of the Major Planets”,
published by NASA Jet Propulsion Laboratory. The calculation data are available and reliable from 1800 AD to 2050 AD.
Most of the calculation precision will be within one arc minute and others such as Jupiter and Saturn will be within a few arc minutes.

3. The Identify function has been improved to be able to identify planets.

4. The inconsistency in Double Star and Variable Star database while scrolling the list has been corrected.

5. In the SETUP menu, we add a Factory Setting function under the SETUP menu.
You may choose to reset the settings to the default settings. Restarting the mount (switching off the power and turning it back on) is
required afterward.
Note: All the settings of Longitude, Latitude, time zone, daylight saving, backlash, PEC data, PAE data and previous alignment data will be
deleted, except for the user defined object coordinates.

Version 3.12 – Release Date 13th March, 2007

1). More options available for alignment star selection
Auto select or manual select, and alignment stars sorted by magnitude or alphabet. See “Alignment Stars” under submenu “SETUP”.

2).”Clear PAE data” added under “Utility”.

3). Three parking positions available:
a. HOME +90 degrees (Northern Hemisphere) or -90 degrees (Southern Hemisphere) in DEC.
b. Current Position Park the scope at currently position.
c. Custom Position Slew and park the scope to the previously saved parking position.
To save a parking position, choose one of the above parking positions under Utility-Park Scope, then turn off the power.
(ESC to cancel and escape from the Utility menu.) If there is a parking position stored in the system, SynScan will prompt “Start from park position?”
at power up.

4). IMPORTANT!! Re-enter the Time Zone data on your hand control after installing the V3.12 firmware.

Version 3.11 – Release Date 17th January, 2007

1. Firmware version and warning message displayed at power up, before the Initializing message.

2. Daylight saving setup required throughout the year instead of just in summer.

3. The hand control displays hour angle and clock position of Polaris after location, date and time are entered.

4. Fix default backlash retrieving bug and set the default backlash as 0°02’00” when the hand control is powered up for the first time.

5. Fix bugs in PEC Training and PEC replaying.

Version 3.10 – Release Date 15th November, 2006 (First version for the V3.0 Handcontroller)

1. GPS function added.
The SynScan hand control automatically retrieves Longitude, Latitude, and Universal Time for initial setup when the SynScan GPS is in use.

2. Criteria for alignment star selection implemented in the software.
The star alignment list contains only the appropriate stars for the time, location, and star alignment method selected.

3. Automatic backlash compensation when under PC control or slewing using directional keys.

4. Adjustable beeper volume under SETUP menu — HANDSET SETTING.

5. PAE function accessible from the UTILITY menu.

6. Temperature and Power Voltage display under UTILITY menu — SHOW INFORMATION.

7. Bugs reported in the 3.01 firmware fixed.