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Astro-Physics AP900GTO with GTOCP4 Complete Outfit Sold!

Price - $6,500.00

Ad Number: 109316

Posted: 27 Jun 2017

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I am selling my venerable Astro-Physics 900GTO German Equatorial mount. I ordered this mount from Astro-Physics (through Company Seven) on 02. February, 1998. Although nearly 20 years old, it has seldom been used. It saw early work in 2000 when I first got into CCD imagery, but then my interest waned until about 2012. It was during the Transit of Venus that year that it saw its only journey outside of my observatory—to the front yard for the transit. Except for this, it has been permanently housed in my climate-controlled dome. I’ve never done any observational work with it, and nothing like supernova searches or anything that would have taxed the motors.
Recently, I upgraded CCD cameras and got back into imaging again. I am upgrading mounts and am offering my 900 to a new home. As mentioned above, it has not seen much use. Just kind of been sitting there. I take it apart periodically to oil the two separate main components. When it was not in general use, I always routinely unparked and parked the mount, just to “stir the tanks” so to speak. It’s never given me any trouble. To this day it has always performed flawlessly, and as far as my recent imagery can testify, it works perfectly. I don’t even use any kind of PEM correction, and just rely on the guider to do my correcting. Ten minute exposures are no problem at all.
There are a few very minor “ding” marks in the paint; barely noticeable. The paint is still a nice color, though there are a few small areas of discoloration. From two foot away it looks practically new. No oxidation, even on the stainless steel counterweight shaft. I am keeping my counterweights, however. Oh, some of the hand controller keypad screw threads that hold the housing together are broken inside (from when I changed out the batteries a few times) but not enough of them to be a problem. The keypad firmware is up to date. The keypad used to have an issue where it would lose power for a fraction of a second (the well-documented “click-pop” phenomenon). But using conductive grease on the internal connectors, and upgrading to the CP4 seems to have remedied this. I don’t use the keypad much since going to APCC, but when I do it is perfectly responsive. The rubber cover does have a small tear in one corner…

In May 2016, I purchased a brand new GTOCP4 control unit for the mount, with all the proper cables. Currently, I have the CP4 mounted on the pier. Further, I am offering an Astro-Physics 8X48PP Portable Pier 48” that has been used one time (at the aforementioned Venus Transit). It is in excellent+ shape. See product list for details.

This mount is turnkey, completely functional, and has had many additional items added to it through the years. The motors are in perfect shape and don’t have any weird noises or the like. I also have most (if not all) of the supplied mounting screws. You’re getting everything from the top of my pier to the top of the declination axis. The scope mounting plate, rings, and the TAK are NOT for sale! Also, please don’t ask me to part with any of the components separate. It’s a package deal. Also, shipping is CONUS ONLY, and I estimate $300 (less sans pier). UPS in original AP boxes (not the ones that came with this mount!). New ones. Any less than this I would gladly refund. Any additional costs, I will pay. Hand delivery/meeting halfway is also a possibility depending on geography.
Astro-Physics 900GTO Servo Drive mount (serial number 900102)
GTOCP4 Servo drive system
GTO Keypad with cover
Power Cable Set for GTOCP4 (CABPP4SET)
Pier/Tripod GTOCP4 Control Box Adapter CBAPT
GTOCP4 long Y-Cable for 900GTO (SGYCR2345)
Standard 14” counterweight shaft (NO counterweights are included), with safety stop
900GTO polar fork assembly (upgraded taller version S900PF-A)
900 Altitude Adjuster Base upgrade (9ALBKIT)
900 Pier Adapter Knob Kit (9KBKIT)
900SPA Pier Adapter Plate (for attaching mount to a pier or tripod of AP specification)
RAPAS adapter assembly (RAP900); does NOT include RAPAS
8X48PP Portable Pier (deduct -$600 if not needed, and some shipping TBD*)
900GTO/GTOCP3 instruction booklet
GTO Keypad v4.19.3 instruction booklet
GTOCP4 instruction booklet

$6500 OBO (+$300 shipping TBD*)

High resolution imagery: https://goo.gl/photo...kuf6smEwaPJa5w8
Recent CCD imagery: http://www.astrobin....ghtObservatory/

Contact me for remuneration options and phone number.


Chris Anderson


  • Condition Excellent+; CP4 new plus other acc.
  • Location Eddyville, KY

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