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AWR Technology (Astronomy - Electronics, Motors, GOTO drives, Sidereal Clocks, Display Units)
Using low voltages for the drive system and motors avoids having mains out at the damp-exposed telescope which is often sited out on wet grass. The PS [Power Supply] can and should be housed safely under cover or [better] indoors, or the shelter of a shed or "warm room." Though this will require an ample, low voltage female/male banana extension cable. Preferably with shielded banana plugs and sockets. As supplied, the power supply will be out beside the telescope with the AWR drive system itself. Probably on the end of a mains extension cable unless you stop and think!
An imaging/Goto PC and monitor are likely to be under shelter unless a laptop is used. It seems logical to keep the only mains voltage item well protected too. The PS is clearly marked for "Indoor Use." Running an extra few yards of several amps at 12V DC will require something slightly better than the absolute, skinniest speaker cable available. If only to avoid voltage drop or heating from internal resistance.
Loudspeaker cables often use banana plugs but the live pins must never be touched together. AWR has overcome this shorting problem locally with the telescopically shielded [male] plugs. The other end of the low voltage cable is anchored in the sealed power supply box. I wouldn't recommend running the PS off a mains extension cable without the protection an RCCD in the UK. Follow best electrical safety practice elsewhere.
Banana plugs are low voltage, single polarity so adding a speaker extension cable of adequate cross section is straightforward enough. This option should be very seriously considered if you want to avoid having mains out at the telescope. The speaker extension cable will run from the shielded male plugs on the AWR's PS captive cable out to the AWR Drive Box sockets.
A red diode shows the Microstep Drive Box has power. While a green diode is provided on the power supply.
Whoops! I should have read the instructions on the AWR website. I was supposed to plug the IH [Intelligent Handset] in after power up to get the initial copyright screen. I later discovered that pressing F4 produced the copyright screen on demand. The system is supposed to start tracking normally once the Copyright screen has changed to default. This may not be what you want if your telescope is parked in a confined space.
To avoid further confusion The Handbook, referred to on the AWR website, is also the IDS Manual. A downloadable, 59 page guide to using the AWR drive system.
For normal use the IDS Manual acts as a useful reference but the Intelligent Handset is remarkably logical in its menus. Provided the telescope mounting is properly set up first a reasonably savvy user should be underway in using Goto control in no time. All seemed to be well on first power up except for the remarkably slow rotation and quietness of the stepper motors to directional button presses. For some reason I had imagined they would literally whizz [scream?] round. Well, all telescope drive motors scream in the YT videos! 😊
The small fans on the Resistance dropper box are rather noisy when close-to. These are to dump unwanted heat. Suggesting they will require some thought in siting the electronic equipment to avoid thermal effects on the telescope image. I am now imagining a flexible hose to warm the poor [old] observer at the telescope. Though I am probably exaggerating the free heat available. Probably a northerly airflow will suffice to avoid heat plumes. 😎
Both motors will happily run simultaneously and in opposite directions. It may be that when following Goto instructions the motors will spin faster? Remember that the motor speed is further reduced by 2.4:1 the pulleys and then by a further 287 times by the worm and wheel. From memory, slew speeds up to half a degree a second are claimed for the system. With controlled acceleration and braking no less. Probably a good idea when swinging a long and heavy telescope across the heavens. Touching any one of the direction control buttons will stop a slew before any unwary visitor is beheaded or the priceless APO refractor dewshield crashes into the dome! Common sense suggests that a new user sets the limits and horizon parameters before loosing his telescope on a Goto tour in a confined space!
IMPORTANT SUN NOTE: A daylight Goto may easily sweep across the sun! [What sun?] Since the actual path of a Goto slew cannot be predicted the OTA should be capped during daylight slews. Or, have a full aperture solar filter fixed safely in place in daylight. For the same reason: Never leave a telescope unattended in daylight if children could ever get near enough to blind themselves at the eyepiece! Do not assume they can not get in! We returned home one day to find several of the neighbour's children enjoying a guided tour of our closed rural garden by a 7 year old. Including toddlers excited by the fish in the goldfish pond! We put a padlock on the gate after that. Following a [forced] lunch break a second drive test followed. Proving that Slew is the fastest mode and the others are very much slower. Literally crawling round [at different speeds] to allow Guiding, Centering and Moving without the danger of overshoot at high magnifications. All perfectly logical if you think about it for a moment. It would require quite some patience to count the number of motor rpm of the other drive rates: [Guide, Center and Move.] It is quite amazing and certainly impressive to see a motor shaft rotating so incredibly slowly for the first time! No intermediate gearboxes either.
Regarding the connection of the AWR system to your PC you must ensure you have a 9-pin [female] serial port on your computer. Not an everyday occurrence these days. At first I failed to realise that the 9-pin ports on both my computers were female VGA outlets for monitor connection. I scratched my head and thought it would be a simple matter of getting a 9-pin male/male adapter. Sadly, life isn't that simple.Update: 3.2.17: AWR Recommends the FTDI USB:Serial adapter and fortunately had them in stock. The image shows the USB to serial adapter. The driver loaded automatically into W10 as soon as I inserted a USB port on my computer. I haven't had a chance to try connecting it to the AWR system yet as it has just arrived in the post. Excellent service from AWR and the postal services! The translucent, blue "shoulders" of the serial plug light up with diodes to indicate when data is transmitted or received.
These USB:Serial adapters are also available from RS but remember that VAT must be added as well as the postage. Cheaper USB:Serial adapters and cables are available but may not work. Some users may want to fit a serial port 'card' into their computer cabinet instead.
Click on any image for an enlargement.
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