Its every Astrophotographer's nightmare scenario, its a beautiful clear night in autumn or winter, your telescope is setup, targets dialed in and shortly after you start imaging, you find frost and dew forming on your secondary mirror! Night over. This is caused because the back of a Newtonian secondary mirror can become colder than the surrounding air during the night, resulting in the formation of dew on its surface from moisture in the air.

A heating element can prevent this problem. However normal heaters cannot be installed on the back of a secondary mirror which is glued to the holder as many are, in this case a wrap around heater like this offers a perfect solution.

Installation:

Installation is very simple. Simply wrap the heater around the stalk that your secondary mirror is attached to (you may have to remove the secondary mirror assembly to properly do this). Then wrap the black neoprene heat insulator around the heater. Use the included elastic band or black electrical tape to secure this in place.

Electrical connection:

The heater wires can be taped down along one of the spider vanes (we recommend using black electrical tape for this). The heater cables are very thin and will have very little affect on the image quality if placed in-line with the spider vane, however as an option, you can also use the included flat copper strip with adhesive backing as a feed to the heater if you have experience with electrics and soldering.

Also included with the heater is a Female-to-Female RCA connector and an RCA extension wire so that you can extend the power lead to your dew controller. We recommend a dew controller setting of 10% to 20% for this heater. Only use higher settings if your mirror is already dewed over and you need to clear it or your observing environment requires it.

Compatibility:

This heater is designed to work with brands such as TS Optics, Skywatcher, Meade, Celestron, Orion and other Newtonians and Dobsonian telescopes with secondary mirrors glued to the holders.
NOTE: Suitable for telescopes whose secondary holder stalk is of a similar diameter to the secondary mirror itself.

Important:
The manufacturer provides the heater with spade terminal connections which adapts to an RCA connection. These spade connectors are not insulated and can cause a short circuit if they touch together, so it is highly advisable to use insulating tape (or heat shrink) on both connectors to stop them from making contact with each other.

Features:

• Used for: Secondary mirrors glued on a holder
  
• Holder size: 2" (approx. 51mm)
  
• Wattage: 10 watts at 100% setting (0.8A current)
  
• Connector: Cable with blade connectors / RCA connector, extension included

Whats included:

1. Wrap-around heater with 15cm cable and spade terminals
   
2. Thermal insulation (neoprene)
   
3. Elastic band
   
4. Adapter cable blade RCA, 40cm
   
5. RCA extension cable, 230cm
   
6. RCA connector changer for the extension
   
7. Copper strip
   
8. Instruction Manual