Takahashi FCT-76 Triplet Fluorite Apochromatic Refractor

The FCT-76 is shown here with its standard accessories in the foreground, except for the dedicated f/4.5 focal reducer-flattener, which is an optional item. This rare little refractor is an older model as determined by its grey-blue color scheme and precision helical focuser. Not many of these little beauties made it to the US, they being primarily manufactured for the Japanese market. In order to make this scope functional for remote imaging I designed, machined and assembled an array of parts to accommodate a Robo-Focus unit employing a cog belt to drive the helical focuser. Below you will find images showing the details.

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The Robo-Focus motor bracket can be locked down (large black knob) once proper tensioning of the focuser drive belt is complete (left)

To adjust drive belt tension, a threaded rod drives a captive end piece to position the Robo-Focus motor bracket (right)

The Tak clamshell ring is affixed to the bottom plate by means of a cylindrical adapter. The Robo-Focus assembly is also bolted to the bottom plate. A Losmandy GM-8 saddle plate is bolted to the underside of the bottom plate, allowing the entire telescope assembly to be firmly mounted on a Losmandy dovetail plate. I usually piggyback this scope onto either the 12.5" RC or Takahashi FSQ-106.

For CCD imaging using the f/4.5 focal reducer-flattener, the following assembly is used; Tak focal reducer, Tak threaded adapter, and custom machined 9mm thick Tak T-thread CCD adapter. The custom 9mm adapter is required to obtain the correct 72.8mm backfocus from the reducer to the
focal plane (left)

Note the black friction tape on the helical focuser. It's there to provide a good mating surface for the cog belt, which would slip on the knurled focuser ring

I use a Particle Wave Technology desiccant plug in the drawtube end when the telescope is stored (right)
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A Pelican 1610 case easily accommodates all the pieces.