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A Question On Dew Heaters

Beginner Equipment
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#1 Matt_C


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Posted 24 September 2021 - 11:27 AM

Hello All,


This is a double barrelled question, but being as it is equipment related, I thought this would be the best place to post. I apologise if it is not.


I am very new to Deep Space Imaging and I purchased my equipment from a well known retailer here in the UK. when I asked about what dew heaters they recommend, the guy said he recommends their own brand, and so I purchased them.


Well, attached are the pictures I have taken of what I received, but I cannot figure out how to power them up.

I assumed that they would plug into the ASIAIR Pro I purchased from them, but they are the wrong connection.


Can anybody advise me of how to power these up?


51511406206_8024c46784.jpgDew Heater by Matthew Cornwell


51511406421_6a7a9c0297.jpgControl Cable by Matthew Cornwell


51512117394_449af97384.jpgUnknown Cable by Matthew Cornwell


The second part of my question is,


At what temperature should I start using these?


It is around 16-17 Celsius or 60 Fahrenheit at night where I am, should I already be using them or is it not cold enough to worry?





#2 Pauls72



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Posted 24 September 2021 - 11:40 AM

Your last picture of an unknown cable, has an F-Connector. It is used to connect the dew heater to a dew controller. A dew controller is used to adjust the power to the dew heater straps.


Dew heaters usually do not need to run at 100%. The goal to prevent dew is to keep the temperature of the optics just a couple of degrees higher than the outside ambient temperature.

Dew comes from high humidity, so if humidty is high you need a dew heater.

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#3 MJB87



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Posted 24 September 2021 - 11:45 AM

Most dew heaters, for reasons I cannot understand, use old-style RCA plugs for connection to a dew-heater controller such as those made by AstroZap. If you want to make that connection, you normally would need a male-to-male RCA cable.


It looks like they also supply you with an adapter cable that allows you to connect the dew heater strip to a conventional 12v-style barrel plug. You have those on the ASIAIR Pro but (not being familiar with the ASIAIR Pro) I can't confirm whether they have finally implemented the power management module to allow ASIAIR to control a dew heater.  You'll want to check that and make sure your version of the ASIAIR Pro can control a dew heater.

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