Kenko NES mount
Even if this mount is branded Konus,
identical to the Kenko NES (including the colors of the knobs!). It's
in both axes and has an excellent tracking, with a very little periodic
error, considering it's compactness and lightness. It can easily track
15 minutes exposures with a 50mm or more without corrections, always
pin-point stars: this is possible thanks to it's great polar finder. On
the mount I've placed a small acromatic refractor (80 mm f/5) and a
75 apo refractor. The first is used as guide telescope and the second
deep-sky imaging. With an aluminum bar I can put also two cameras, plus
one piggybacked on Pentax 75 plus one on the counterweight bar. It's an
interesting solution for meteor imaging.
The mount work very well with the ST4,
that I use when I take 40 min exposures with a 200 mm lens or Pentax 75
Some views of Kenko
Nes with the Pentax 75 apo and the 80mm f/5 refractor. Note the 6 kg
(green): the big overload is well supported by the mount that track
well for deepsky imaging.
Graph of the
error of Kenko NES: it's quite irregular, but the amplitude of the
is however small for such a small mount, about +/-20". Click for
the reader will assume the risk for all the modifications here propose,
moreover the warranty will be void.
- Autoguider interface, with ST4 standard, to
autoguide with any autoguider camera. The modifications are
- 1 RJ12 6 pin socket
("phone" socket) [the standard phone
jack is 2 or 4 pins and is named RJ11, while the 6 pin option is named
- 10 cm of coloured
- unconnect all the
power and motor cables
- open the front panel,
unscrewing the four screws
- gently extract the
- solder the coloured
wires to the buttons using the scheme in the figure bottom-left
- connect the wires to
the RJ12 socket using the order in the figure bottom-right
- glue the RJ12 socket
to the bottom card, under the +X button
- cut a window on the
side of the handbox, using in example a "minidremel" tool
- put all together
again and test with a tester
- if all is ok, than
carefully test with your camera and telescope
|Complete view of the
modified handbox, with the AR cable (black) and the one to connect the
ST4 (grey, "TIC" cable) . The other cables, for the DEC motor and the
+12V power supply are not connected. Please note that the power supply
connector has the ground in the center, so be aware of not inverting
because you can burn the handbox!
To connect any autoguider with RJ12 output, simply use a 6 pin "phone"
cable with RJ12 plugs at both sides.
|Detail of the handbox with
the RJ12 socket on the side.
|Comparison between the
handbox without and with the front plate. After removing the
transparent protective sheet with the "Konus" brand, the "Kenko"
writing is visible, revealing the original manufacturer. The "Kenko"
writing is also reported on the electronic cards.
|The electronic cards with
the RJ12 socket glued.
|Detail of the buttons and
the contacts to be used to connect the autoguider port. The colors of
the wires are the same of the RJ12 socket of the figure on the right.
|Schematics of the pinout of
the RJ12 socket, assuming the SBIG specifications. All connections are
N.O. (Normally Open).