QUESTAR POWERGUIDE II DRIVE & CORRECTOR

The original internal Powerguide system of the 1980's and its successor the Powerguide II are each an electronic regulated drive and corrector system powered by one 9 volt battery that allows the user to operate the Questar at a precise Sidereal or Lunar rate anywhere in the world - north or south hemispheres, completely independent of wall current or other external power sources. The Powerguide also provides the means to vary the rotation speed of the Right Ascension motor to make fine tracking adjustments. The internal Powerguide systems are arguably the most important innovation that has been developed for the Questar since its introduction.

Powerguide II can only be installed either when the telescope is ordered new, or if it is returned to us for the retrofit. It is not recommended for the consumer to attempt install this option. Furthermore, since Powerguide II requires adding a new, thicker cover plate over the bottom of the base, some modifications may need to be made to the Questar Carrying Case in order to accommodate a slight increase in the height; we can usually accomplish this at no extra cost.

Right: Questar Duplex with the Powerguide II controller, in Pole Aligned orientation on provided table top tripod legs (136,956 bytes).
Click image to see enlarged view (304,898 bytes).

Background The Questar 3-½ and Questar Seven telescope drive fork bases are furnished with a fork style drive base with a set of three very lightweight alloy legs. The legs thread into the drive base at two points on the side, and one at the bottom to form a tripod that is adjustable for latitude. This tripod permits the telescope to operate off of a table top. Alternatively, the telescope may be Pole Aligned atop an optional field tripod such as the Questar Tristand. The fork mount is normally provided with a 120 Volt A.C. (or 220 volt optional) motor system with an AC power cord. The AC cord plugs into a wall outlet and this starts the fork tracking at a Sidereal rate that permits accurate tracking of stars, planets and most other celestial objects as the Earth rotates. Since the motor is a non reversible synchronous motor one must specify either North or South Hemisphere when ordering this drive system. This basic arrangement is completely satisfactory for a person who operates the telescope for viewing only from one location that has A.C. power such as at a school, or on a home deck.

Powerguide II is the optional quartz crystal frequency regulated drive system for the Questar. A drive base equipped with Powerguide II incorporates a servo motor with drive corrector circuitry powered by a common alkaline 9 Volt D.C. battery housed in the hand-held controller. The endurance of this highly efficient system provides up to fifty (50) hours of service and even longer with a 9 volt lithium battery. This capability to operate form a battery eliminates the need to be located near an AC power source.

   

The hand-held control paddle controls all functions including the selection of drive rate (Sidereal or Lunar), fine speed correction changes of ±1.4 or 10X Sidereal. All control is done with the "On Off" switch and four (E-W-N-S-) push buttons; there are no switches on the drive base - all is on the hand paddle that plugs into the bottom of the base. An internal Quartz reference circuit continuously checks motor speed every 0.6 Arc Sec. and adjusts it as necessary. But the most important aspects of this option are that it frees a person to travel around the world, to the North or South Hemisphere independent of external power supplies.

The development of the 9 volt Powerguide systems was accompanied by the introduction of an optional Motorized Declination Assembly for the Questar 3-½ Fork. This accessory includes a Declination Hand Control wheel that replaces the original, and the Motor and Support Frame that is attached onto the Fork Tine meshing with the new Declination Hand Control wheel. The Questar 3-½ Motorized Declination Drive and the Questar Seven Motorized Declination Drive options are for use only with those Questar Fork Mounts that incorporate the Powerguide II drive and control system.

The Powerguide II consists of several components:

• Power and Signal Cable
  

• Powerguide II Hand Held Controller
  

• 9 Volt Alkaline Battery (Lithium battery recommended for longer life or operation in extreme cold climates)
  

Set up and Operation:

• Pole Align the Questar Fork Mount. The drive will not track accurately without the mount being reasonably well oriented to the celestial pole.
  

• Connect the provided six pin module cable from the jack at the base of the Fork Mount into the top left jack on Powerguide II Hand Control. Note, the six pin should be plugged in only into the jack on the left side; the right side jack accommodates the cable that connects the Motorized Declination Vernier Drive.
  

• For Northern Hemisphere Sidereal operation slide the power switch to "On"; this is the default startup setting. The red LED should light indicating proper operation. For reversed motor operation in the Southern Hemisphere press both the North and South direction buttons while simultaneously sliding the power switch to "on".
  

• To set Northern Hemisphere to the slightly faster Lunar rate press both the East and West direction buttons while simultaneously sliding the power switch to "on". For Southern Hemisphere Lunar rate reversed operation press all four the North and South and East and West direction buttons while simultaneously sliding the power switch to "on".
  

• Right Ascension functions are controlled by the left (West) and right (East) push buttons, while Declination with the optional Declination Motor are controlled by up and down buttons. Note for Southern Hemisphere operation, these directions will appear reversed.
  

• Pressing either the North, South or West buttons accelerates the R.A. or Declination drive motors to fine adjust centering a target by moving at 1.4 x the standard Sidereal rate, a 35% speed increase. Note pressing the East button stops the R.A. drive motor so that the Earth's rotation causes the object to drift apparently to the East, releasing the East button resumes tracking. These functions are reversed for Southern Hemisphere operations.
  

• Pressing the North, South, East or West buttons while then pressing and holding the opposite direction push button accelerates the R.A. or Declination drive motors to 10 x the standard Sidereal rate, a 1000% speed increase. This is useful for initial centering of a target that is far off center, or for perusing through an area of sky congested with targets.
  

Note: the Powerguide II is expressly designed for use only with the Powerguide II Motorized Declination Drive, and not with that of the original Powerguide. Any attempt to use the Powerguide II or its Motorized Declination Drive with any other system is likely to result in damage to the motors and possibly to the controller as well.

Company Seven recommends this as a fine positioning aid, it is not designed as a slewing motor to drive the telescope across large areas of the sky.

Right: Questar Powerguide II Cable Socket in the bottom of the telescope Base (83,030 bytes).
Note this is where the Serial No. is engraved on a Questar Standard 3-½ or Questar Duplex telescope. Click image to see enlarged view (323,230 bytes).

Below Right: Questar Powerguide II Hand Control with Cable (79,888 bytes).
Click image to see enlarged view (200,400 bytes).