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A 5m long yellow cable is a Cat6 network cable is provided for connection of the IH to the
Microstep drive box. Allowing plenty of freedom to move around the
telescope. Or even reach the workshop/warm room. If only I had one! It
reached 25F or -4C inside the workshop a couple of days ago and the entire mounting is still sparkling with hoar frost! The cables to the stepper motors are also very generous in length and all have latched plugs and sockets. Though I do feel a cable anchor at each end of the IH cable might be useful. There is a guard on each end of the cable to stop accidental contact with the little latching/release tabs. However, the vulnerability of this cable in the dark places rather a lot of trust in the relatively fragile little plugs.
A second socket on the base of the IH provides a connection to a PC for point and click control using Stellarium or similar 'planetarium' software. Which is a very useful provision because it saves a further length of cable to reach the PC from the drive box. BTW. Stellarium may need a special download from their website for telescope click and Goto control. Later editions have a small telescope image on the bottom line to show the telescope control is lying dormant and ready to be resuscitated.
King refers to standard [stellar] drive rate.
--- Shows a code letter W, P or C depending on what is happening.
LST is Local Sidereal Time.
SITE A is one of four possible locations. Lat & Long are easily stored [to the nearest second of arc] to avoid repeatedly entering locations by hand if regular but different observing sites are used. Many amateurs must escape from light pollution at their own home. So they drive out into the countryside to a familiar spot free of extraneous light. AWR can still work even in the Outback with a properly fused 12V battery. Most car and motorcycle batteries can easily fry an egg if short circuited! Both leads to the AWR Microstep box terminals should be fused. AWR recommends inline car fuses of suitable ratings.
I
like the way the text almost fills the small screen rather than
demanding a microscope to read undersized text. Old age and reading
glasses often come hand in hand. Needing glasses at the telescope, just
to read the screen, would probably wear thin after a while. I think I
shall be able manage without. Though a square [plastic?] magnifying
glass could be taped over the screen for easier legibility if it proves
necessary in practice. Luckily I only have one dioptre of reading error so I am
hoping the lit screen is easily legible when lit. I captured a couple of short videos to show the huge differences in drive speed [i.e. stepper motor rotation] but they [the videos] were much too amateurish [i.e. shaky] to share online. First I need to arrange both motors and the full IH in simultaneous view with the camera on a steady tripod. Capturing the screen readout will need some care to be useful to curious YT viewers. Mental rehearsal will help to avoid wasting the valuable time of the viewer. Far too many YT video makers waste huge chunks of viewer's time where nothing useful or interesting is happening on screen.
I would guess [very roughly] that the fastest [Slew] motor shaft speed is about 90rpm. It is slightly too fast to count full rotations by the usual "one thousand, two thousand,"
verbal system without hurrying unduly.The 14/34 pulleys and belt provide a reduction of 2.4:1. So say ~ 38rpm is applied to the worm shaft. 38/287 = ~0.13rpm on the mounting's axes. 0.13/60x360 = 0.8 degrees per second. AWR claims their system should slew at about half a degree per second. To move the telescope from fully East to West, over a full 180 degrees, would take between two and three minutes. Though remember that this figure is is based on a very rudimentary rpm count. Only an active system with a real telescope would indicate the correct speed of a slew. Those who want faster slews can obtain them from AWR, at a price, for a 24Volt 'turbo' system.
I watched the Dec screen reading change on the handset as the Dec motor was slewed and would judge the movement was just under one degree per second. The motor shafts, despite crawling around almost invisibly on the slowest settings, were impossible to stop by hand. I gripped the small pulley as tightly as I was able during normal RA [stellar or King rate] drive and the motor never missed a beat. There was absolutely no change in sound or anything to suggest it was struggling to rotate normally. Multiply that power by 2.4 for the pulley gearing and the torque more than doubles. Multiply by 287 and it should be able to lift the mounting right off the ground! Albeit rather slowly. So some care must be exercised to ensure nothing ever blocks the movement of the wormwheels or the OTA.
Lest ye consider the suggested slew speeds pedestrian: It should always be remembered that an accurate Goto will save an enormous amount of the observer's time in not having to search for an object. Particularly a dim one. In fact Goto may be the only way for some observers to find many objects in light polluted conditions. Including full moon. Though it is not usually chosen as a Goto target. Unless, of course, you live in Beijing! Moon? What moon? 😵
Click on any image for an enlargement.
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