Dew Guard


Dew Guard

Regular price
$ 42.00
Sale price
$ 42.00
Unit price
Only 2 Left!

In Stock


AstroSystems amazing Dew Guard secondary mirror heating system automatically senses the air temperature and the mirror temperature, then maintains the secondary at a preset (adjustable) temperature above the ambient air temperature. Gently warms the secondary at 2-4 watts when on full. The DG-1 has 4, The DG-2 has 6 and the DG-3 has 8 evenly spaced contact points for optimal thermal distribution. Uses any external 9-15 volt dc supply or you can run on a 9v battery mounted at the holder, eliminating the need for wires across the spider. Note: 9V rechargeable NiCd or NiMH batteries will not work, they are only 7.2-8.4V and have low capacity, rechargeable Lithium cells are 9V and will function properly. No more heat ropes! Three sizes to choose from.

DG-1 fits 1.3-2.1" Mirrors
DG-2 fits 2.6-3.1" Mirrors
DG-3 fits 3.5-6.0" Mirrors

Note: If your secondary is glued to a center post, the Dew Guard cannot be used. If your secondary is exposed and not inside a shroud the Dewguard will not be effective in controlling dew.

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