Avalon Instruments M-tre User manual

M-tre
USER MANUAL
Version 1.0.0. October 2023
All the pictures and contents included here are propriety of AVALON INSTRUMENTS.
They cannot be reproduced, published, copied or transmitted in any way, including the internet, without the
written permission of AVALON INSTRUMENTS.

SAFETY RECOMMENDATIONS AND WARNINGS
•Read carefully the manual before nstall ng and us ng the mount.
•Use the power cable suppl ed w th the mount or a 12V- 3A stab l zed power supply
as suggested n the manual.
•Connect the power cable correctly and securely to the power socket.
•Do not bend, pull or press the cable as th s may damage t.
•For any ass stance or repa r, please contact only the manufacturer.
•Be sure to remove the power supply at the end of ts use or before any clean ng or
ma ntenance.
•Th s mount must be used exclus vely by adults, do not allow use to ch ldren or to
people w th reduced mental capac ty.
•Avo d to operate the mount except as str ctly nd cated n the manual.
•Mod fy ng or alter ng n any way the character st cs of the mount w ll vo d the
manufacturer’s l m ted warranty.
•Never mod fy the tens on of the belts (by ded cated screw), these s set n the factory
and any unauthor zed change w ll vo d the manufacturer’s l m ted warranty.
•After us ng t, avo d to store the mount n areas exposed to sunl ght or n wet places.
IMPORTANT NOTE: DO NOT USE ANY KIND OF LUBRICANT, SPRY, LIQUID OR
OIL ON THE BELT DRIVE SYSTEM!!!
Any use of lubr cants w ll vo d the manufacturer’s l m ted warranty.
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Table of Contents
SAFETY RECOMMENDATIONS AND WARNINGS.....................................................................................................2
Technical Specifications.......................................................................................................................................................
Forewords..............................................................................................................................................................................5
1. Packing Content................................................................................................................................................................6
2 Mount Description.............................................................................................................................................................7
3. M-tre Initial Setup.............................................................................................................................................................9
3.1 Latitude Range Setting............................................................................................................................................10
3.3 Telescope installation..............................................................................................................................................13
. Telescope Balancing.......................................................................................................................................................15
.1 Dec Balancing..........................................................................................................................................................15
.2 RA Balancing...........................................................................................................................................................17
5. M-tre mount stationing....................................................................................................................................................19
5.1 Latitude Fine Adjustment........................................................................................................................................19
5.2 Azimuth Regulation.................................................................................................................................................20
5. StarGo2 Pro installing.............................................................................................................................................21
5.5 Cables connection....................................................................................................................................................23
5.3. More modern and precise approaches to Polar Alignment.............................................................................26
5.3.5 Dual Axis Alignment......................................................................................................................................26
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Techn cal Spec f cat ons
Type of mount Single Arm Equatorial Fast-Reverse
Mount weight 35 Kg
Maximum load 38 kg single telescope setup, 50 kg double telescope setup
Motion System Four-step reducer via pulley timing belt system on ball
bearings, with no play on both axis. (Belt Drive System)
Construction
Materials
Machined from solid blocks of anodized aluminum with high
precision CNC machines
Transmission System Pulleys made with special polymer + fiber glass and high
quality toothed belts
Encoder 21 bit Absolute encoders
Control System StatGo2 Pro Multiplatform Astronomical Control System
Dovetail Plate Losmandy, 3" (75mm) dovetail, single knob with 2 tightening
points
Warranty 2 years from the purchase date, 5 years for the transmission
system (Belt Drive System )
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Forewords
This manual describes the Avalon M-Tre mount, the procedures for its mounting on the
Adjustable Angle Pier and for the installation of a telescope. Additional Information on the M-
tre mount and on the StarGO2 Pro control system, containing also the procedures for the use
with third-party software and in particular with the INDI and ASCOM and Alpaca ASCOM
drivers, are reported in the StarGO2 Pro manual which is part of the mount supply.
A careful reading of this manual will enable the use of your mount safely and with the
maximum satisfaction.
The mount design and its configuration could be subject to modifications, without prior
notification, based upon designer’s improvements and the requests, if applicable, by the mount
users.
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1. Pack ng Content
Open the box to take all the content out. Extract all the components from the small cardboard
box and from the mount bag side pocket putting them on a clean, flat surface.
Component L st
•Mount Head
•StarGo2 Pro Box
•StarGO control Keypad
•125/2 0 VAC / 12 VDC power supply
•Metric Hexagonal key set
•RS232 Cables
•USB Flash drive with softwares and manuals
•RJ11 RA/DEC motor cables
•Attachment screws
Package picture
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2 Mount Descr pt on
The M-tre is a single arm fork Dual Dec mount devoted to deep-sky imaging in the capacity
range up to 35 kg single telescope setup and 50 kg in double telescope setup.
The M-tre design was developed on the basis of the M-uno, making use of the same technical
concepts:
•Fast Reverse technology
•Computer aided design (CAD)
•High quality manufacturing with digital control 5 axes CNC machines (CNC + CAM)
•Absolute quality materials: Anodized aluminium from milled mono-bloc, stainless steel
components and screws, brass components, techno-polymers
The M-tre motion transmission technology is based on pulley-tooth belt without play, while its
peculiar geometry makes easy the imaging at the meridian crossing regardless the typical
problem affecting the classic German Equatorial Mounts, for both the risk of touching the tripod
and the need of waiting for the object cross the meridian.
Moreover, considering that at the meridian the sky is less subject to light pollution and to
atmospheric turbulence, the M-tre is the ideal tool to shoot deepsky objects in their best
conditions, close to the meridian, especially when the time is short and the sky is not so dark and
clear.
Another M-tre basic advantage is that counterweights may be not required.
Its declination axis can be quickly balanced like in an equatorial mount, while, for the RA axis,
it is possible to fix the arm on several possible positions and to make the fine balance using a
very small counterweight.
The M-tre mount, is equipped with the new StarGo2 Pro Multiplatform Astronomical Control
System.
The use of pulleys and toothed belts has allowed to obtain several advantages: a really steady
motion without play (no backlash) and sudden peaks, factors of paramount relevance for long
guided exposures and during high magnification visual observations. These features are of
particular relevance especially for the declination axis motor that can now quickly reverse the
motion without breaks to recover the plays: from here the mount name FAST REVERSE. The
toothed belts used in the M-tre have the structure made of special material with steel strands to
avoid any deformation, elongation and stress, much better than those used in the automotive
engine distribution system (which are generally made of rubber with nylon strands).
Considering that the service time for the automotive toothed belts is around 100.000 km (60.000
miles), assuming a medium regime of 2.000 rpm and thermal stress from 0 to 90°C (30 to 195 F)
in a few minutes, we can think that the life cycle of the M-tre toothed belts will be extremely
long ! It is important to underline that in the gear-worm systems the motion transmission has
only one tangent point of contact, any errors on each of the two components will, sooner or
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later, result into a tracking errors. On the contrary, in the pulley-toothed belt system, no direct
contact occurs between the pulley and the motion is transmitted by the belt engaging from 50%
to 90% of the girth surface. Consequently any error, eventually present, is averaged among the
cogs, moreover soft, greatly reducing the tracking error.
No wearing effects since no relevant frictions occur. In fact, all the pulleys and the axes rotate
on roller bearings that allow to reduce the total friction almost to zero.
Another significant advantage of very low frictions is that the risks of motor slipping during
GOTO operation is virtually null. On the contrary, it is well known the difficulty to regulate the
coupling between gear and worm in the conventional mounts. If the coupling is tight the motors
can stuck with consequent loss of the position, if the coupling is too loose the plays increase. On
the other hands, the absence of significant play in the M-tre makes the initial calibration of
guiding CCD quick and easy.
Since there are no gears, there is no need of periodical lubrication of the internal components
and therefore the maintenance is extremely reduced and limited to the external cleaning.
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3. M-tre In t al Setup
The M-tre can work at latitudes range from about 35° to about 60°. This mount comes with the
latitude preset adjusted at 5°, so the first operation to perform, is the regulation of the latitude
to the value related to the site in which the mount will be used. The same operations will be
carried out in the case the mount is transferred in a site with a different value of latitude. This
operation will be described in the section 3.1 below.
It is strongly recommended that the M-tre mount is used with the Avalon Instruments T-pod
tripod which has been designed to guarantee maximum performance. If a different kind of
tripod is used, it must have dimensions and characteristics compatible with the mount weight
and with the astronomical load to be installed. Section 3.2 describes the mount installation on T-
Pod tripod.
In order to contain as much as possible the overall packaging dimension, the mount comes in the
package with the t-pod adapter flange already assembled.
Remove the three flange fixing knob.
Remove the flange from the mount bottom and
fix it on the T-pod or on a Pier as shown in the
image on the right.
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3.1 Lat tude Range Sett ng
This section describes in detail the procedures to switch set the correct range of latitudes of the
site where the mount will be used.
The following are the steps to adjust the mount’s latitude range
Rough lat tude range sett ng.
Choose the correct hole
Loosen the lateral bolts that is
currently holding the mount
lateral base flange, then loose and
remove the bolt that is holding the
adjustment cylinder in it’s
position hole position hole.
NOTE: due to the M-tre weight
it’s better to perform this
operation in at least two people,
while one unscrew the bolts, the
other should hold up the mount.
Move to upper holes for low
latitudes area, move to lower
holes for higher latitudes area.
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F ne lat tude range sett ng.
Rotate the knob
Once the correct latitude range
hole has been set, is possible
move of few degrees up or down
by rotating the latitude knob
shown in the picture on the right.
If by hand the knob rotation it
may feel to hard to move, it is
possible to use the provided knob
latitude key, as shown in the
picture on the right.
The following are the steps necessary to perform the fine Azimuth adjustment on the M-tre
Loose the azimuth adjustment knobs and
perform a few turns of the two lateral
Azimuth adjustment knobs by rotating them
in opposite directions.
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The two lateral Azimuth adjustment knobs
press on the corresponding pin, allowing the
fine Azimuth rotation.
When the fine Azimuth adjustment has been
set, is possible to tight the mount fixing
knob.
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3.3 Telescope nstallat on
After the mount has been placed and secured on the T-pod, the next step will be the positioning
of the Telescope on the M-tre. and to perform the Polar Alignment.
Place the mount arm in the position shown on
the right picture, unlock the declination bolt
and rotate the axis until the female dovetail
saddle is horizontal. Firmly lock both the axis
bolts. Firmly keep the OTA and insert its male
dovetail plate into the female saddle, making
sure that the side closer to the ground goes in
first, as shown in the picture.
The declination axis can be unlocked by
loosening the DEC axis blocking bolt by using
the provided key
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While holding the telescope with one hand, use
your other hand to rotate the knob on the
dovetail saddle clamp, as shown in the right
picture, until it is firmly locked.
Before leaving the telescope, be sure it has
been securely attached by making certain that
the male dovetail bar is in close contact with
the female saddle and there is no space
between them.
Test the saddle’s locking knobs as well as the
RA and DEC clutch levers to make sure they
are tight
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4. Telescope Balanc ng
To guarantee a precise mount tracking it is necessary to correctly balance the telescope in both
the rotation axes. To perform this operation is needed to move manually and freely the telescope
in RA and DEC. As anticipated, the M-tre is provided of latches in both axes. To freely move
the telescope, the latches need to be released by rotating the related levers in the counter
clockwise direction.
Note: Before performing the balancing of the telescope be sure to have the full control of it
before releasing the latches. An over unbalanced mount can move very quickly causing
damages to the optical tube or to the mount itself.
4.1 Dec Balanc ng
To obtain the best tracking performance from the mount, the telescope must be balanced in both
axes. Even if the telescope does not track in Declination, it must be balanced on this axis to
avoid sudden movements when the declination knob is unlocked. Good balance also helps to
prevent vibrations and overly-quick responses while guiding and reduces strain on the motors.
With the M-tre mount it is better to start balancing the DEC axis rather than the RA axis. The
M-tre is unique in that it allows the RA axis to be almost automatically balanced with any
telescope.
Before beginning the balancing operation, it is worthwhile to test the saddle locking knobs to
make sure they are tight. Telescopes do not like to being dropped!
Perform the following operations:
•Unlock the RA axis knob and move the arm of the mount to an equilibrium position, as
seen in the image, and re-tighten the RA axis knob.
•Loosen the DEC knob and move the telescope parallel to the ground as seen in left
picture, but do not let go of the telescope.
•Move the tube SLOWLY and CAREFULLY – to see in which direction, if any, it rotates
around the DEC axis. If the front end moves down, the telescope must be moved
backwards in the mount. If the front end moves up, the telescope must be moved
forwards. To do either of these, maintain a good grasp of the OTA and slowly loosen the
dovetail knob on the mounting saddle.
•Move the tube back or forth in the saddle, depending on whether it moved up or down,
until it stays in a horizontal position by itself when you remove your hand.
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Note: Always lock the clamp before check ng the balance w th the new tube pos t on! If
the tube rema ns stable n a hor zontal pos t on when the DEC knob unlocked, the DEC
ax s w ll be balanced. T ghten the doveta l clamp to f rmly lock the telescope tube n ts
new pos t on. Do NOT leave the telescope wh le the doveta l clamp s loose. In the unl kely
event that your telescope should fall off the mount onto the ground, t could ru n your
ent re day.
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4.2 RA Balanc ng
Balancing the M-tre mount in the Right Ascension axis is different from the other German
Equatorial Mounts, but it is quite easy to do. The balance is performed in two phases, one raw
and the other more precise.
Raw Balanc ng
After having placed the telescope on the clamp and having found the fine DEC balancing, the
user should have noticed the balancing behaviour on the RA axis.
The M-tre (as the M-zero and the M-due mount) allow to move the DEC arm in several
positions toward the RA axis. This feature help to find a fine balancing by using as less as
counterweight possible.
On depending on the unbalancing level noticed in the previous operation, the user can be aware
about the best DEC arm position to use for his setup.
Normally, the more the telescope weight, the lower should be the DEC position.
In case the user needs to change the DEC arm position from the one provided, the following
procedure must be followed.
Place the mount on a flat and anti-scratch
surface. The foam cover that comes with the
packaging may be useful for this purpose.
Put the arm of the mount parallel to the
ground as seen on the right picture.
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Unscrew and set aside the four screws
holding the lateral bracket on both sides of
the mount. Then remove the lateral bracket.
In case the lowest position will be required, it
is possible to reverse the lateral bracket, as
for the M-zero mount.
Warn ng: do not use d fferent screws other than those suppl ed or ser ous damage to the
gear system may occur!!
Prec se balanc ng
Once the mount arm has been set in the correct position for approximate balancing, tighten all
screws and, if necessary, perform the fine balancing. This is performed by mounting the small
counterweight, its shaft and the female dovetail as shown in the previous picture above. Insert
the counterweight in the shaft and slide it in the equilibrium position. When that is
accomplished, firmly tighten the counterweight locking knob and the shaft end knob. Of course
all the precise balancing operations should be performed with the telescope installed.
NOTE: Most German Equator al mounts are based on worm gear technology. They need
to be sl ghtly unbalanced n the easterly d rect on to avo d any unwanted pendulum-l ke
behav our when cross ng the mer d an. The M-tre’s toothed-belt transm ss on technology
el m nates the need for th s small amount of east-b as unbalance. Th s s a major
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mprovement because once the M-tre s balanced, the counterwe ghts do not need to be
moved at all. The des gn prov des a level of stab l ty that s most apprec ated dur ng long
exposures and remote observ ng sess ons.
5. M-tre mount stat on ng
Before using the M-tre mount it is necessary to position its polar axis parallel to the earth’s axis
of rotation.
In this chapter the operations to trim the latitude and the azimuth and to perform the mount
alignment to the celestial pole using the standard polar scope (or the optional alternative) will be
described.
5.1 Lat tude F ne Adjustment
During this operation the mount arm must be kept in its equilibrium positiont. After leveling the mount base using
built-in the bubble level, the next step in this process consists of approximately setting the polar axis at an angle
equivalent to the latitude of the observation site. For example Rome is about 2° North, Milan and Venice 5° North
and Palermo 38° North. Refer to the latitude scale on the side of the mount.
The latitude adjustment must be performed
using both hands to turn the two latitude
adjustment knobs in conjunction with each
other. While one hand is tightening the front
knob, the other hand should be loosening the
rear knob and vice-versa. To increase the
latitude (i.e. raise the polar axis), the rear
knob must be turned in the clockwise
direction while the front one is turned in the
counterclockwise Direction. To lower the
axis, the opposite actions are performed.
NOTE: It is generally better to perform the
fine latitude operations against the force of
gravity, that is, by raising the mount.
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5.2 Az muth Regulat on
The azimuth regulation is performed in a similar manner, using both hands to turn the other two
adjustment knobs in opposite directions simultaneously. When a knob is rotated in one direction
the other is rotated in the opposite direction. Turn them so that the screws attached to the knobs
press against the brass adjustment post and move the mount to the right or left by a small
amount. The azimuth adjustment knobs are those positioned on both sides of the mount as seen
in the picture on the right.
Remember that setting up the mount in both Latitude and Azimuth should be performed only during the
important phase of precise polar alignment, before starting an observation or photographic session. Once
the polar alignment has been reached, THE MOUNT SHOULD NOT BE MOVED FOR ANY
REASON USING ALTITUDE OR AZIMUTH KNOBS OR THE ALIGNMENT WILL BE LOST.
After the alignment has been established, moving the mount in Right Ascension and Declination and
pointing the telescope to celestial objects should be performed only by using the keypad or the software
commands.
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