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View Full Version here: : Does Thousand Oaks have a retailer in Australia? Looking for a great Dew Heater


g__day
05-05-2023, 01:27 PM
Hi all,


I am looking for a Dew Heater for my scopes - going through old threads I see most folk recommend the Thousand Oaks Four Channel Digital Dew heater - way above the Kendrick one; do they have any distributor / retailer in Australia - or is it order it from USA and ship it?

Many thanks,


Matthew

gbeal
05-05-2023, 01:34 PM
If you draw a blank, message me Matthew, I know of a guy who has a flash dew heater controller, he's just to lazy to list it.

MortonH
05-05-2023, 02:32 PM
Bintel sells Thousand Oaks solar filters but Kendrick dew heaters for some reason!

gregmc
06-05-2023, 08:59 AM
Re manual dew heaters, they are not great. Manual are basically a simple manual control pulse width switch. Discreet technology that been around so long I can’t see how it can be mucked up.

Manual control usually means either too little or too much heat but you have to watch it during the night. Too much will cause unnecessary hot air movement and chew up excess power if using a battery.

A good system provides some feedback from the heated surface via a sensor and the controller provides just enough power to keep that surface a set amount above the ambient air temperature (measured by another sensor)
Kendrick does a nice controller such as this. So good is individually keeping a surface just above ambient.

A great controller measures the ambient temperature, relative humidity and calculates the current dew point.

It the applies power to the particular strap while measuring the surface to get that surface above the dew point. This system uses the least power, supplying the least heat automatically.

The celestron 2x and 4x are examples. The Pegasus is a bad example as they don’t have the individual feedback sensor.