Kendrick Dew Remover System


For many years, Astro-Physics has carried the Kendrick Dew Removal System. Jim Kendrick innovated the concept of dew removal systems in the mid-1990's to meet a persistent need in the burgeoning astronomical community for effective dew removal and prevention. His system quickly became the benchmark for dew prevention.

We are pleased to say that we believe the Kendrick Premier Dew Removal System to be the most appropriate setup for a large portion of our customers.The Kendrick Dew Remover System was developed to meet the need in the astronomical community for an effective dew removal and prevention system. This system has heaters for almost all the optical components used in amateur astronomy. Repeated field testing on many types of optical systems under many conditions and hundreds of satisfied customers has proven the effectiveness of this product over and over. It also has these other attractive features:

  1. Energy efficiency - Variable settings on the controller allow maximum conservation of battery power.
  2. Heat range adjustable.
  3. Lightweight.
  4. High quality manufacture.
  5. Versatiliy - Capable of keeping every optical surface moisture-free during an observing or astrophotography session.
  6. Guaranteed to be effective thus extending your observing time on dewy evenings.
  7. Radio frequency interference free.

We are pleased to introduce a few additional products to our line-up.

Dew Controllers

Kendrick Premier Controller (KDRPC)

Note: The Kendrick Premier Controller will be available in the fall.

Astro-Physics is pleased to offer the Kendrick Premier Power Controller Package. This is the most advanced controller of its type. The controller shown in the images here is called the "Observatory" version. Unlike the standard version, it has no display.

There are two versions of it (both remotely controllable). One has a touch screen and another (known as the Observatory version) without any screen at all, designed strictly for remote control. A remote control web app is also underdevelopment and is looking very nice!

Both version (Observatory and Display) can be operated remotely, using either:

  1. USB to PC for local remote control.
  2. Bluetooth to Android devices for local remote control.
  3. RJ11 (using RS-485 communication protocol) for long distance remote control.

Here are some of the new controller specs (specs may change without notice):

  • 3.5" touch screen, (resolution 320 by 240).
  • An Observatory version of the controller without a touch screen and designed for users with dedicated remote control observatories.
  • 2.5mm Audio Jacks for optic sensors.
  • USB-A port for External ambient and humidity sensor (various cable lengths to suit your needs).
  • USB-B remote control port for short distance communication.
  • RJ11 port for remote control port for long distance communication (over a kilometer possible).
  • RJ11 port for connection and remote control of peripheral devices.
  • Bluetooth capable. Android app under development
  • Remote control via a web browser. Web app and tiny remote web server under development.
  • Mating Terminal Block power input. This will allow users to terminate the controller power cable in a connector of their choice.
  • New optic sensor design.
  • Operating voltage 12 to 28 vdc.
  • Upgradeable firmware via the internet.
  • 3 dedicated 12 volt power ports to power peripheral devices.
  • 2 of the dedicated 12 volt power ports will be probramable down to 8 vdc to allow powering of DSLR cameras.
  • LEDs on the heater ports.
  • LEDs on the programable power ports. (LED will come on when that particular port is programed at 8 volts DC to differentiate it from a 12 volt port)
  • LED for power on.
  • ON/OFF switch

The feature functions that are built into the firmware are:

  • Temperature sensing.
  • Humidity/Dewpoint sensing.
  • Optic temperature above ambient temperature control.
  • Dewpoint control.
  • Fixed temperature control.
  • Power to heater % control.
  • Choose Celsius or Fahrenheit screen display.
  • Screen brightness control.
  • Night Mode red screen.
  • Low voltage cut-off. For those who do not want Low Voltage Cut-off, this function can be disabled via the display screen and/or the remote control software.
  • Battery voltage display.
  • Air temperature, Optic Temperature, Humidity and Dewpoint display.

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Kendrick DigiFire 12 Controller (KDRDF12)

Also new to the controller line-up is the Kendrick DigiFire 12. This mid-range power controller is perfect for those astronomers who don’t require the full functionality of the Premier Controller but still want enhanced digital control of their dew removal system.

Features include:

  • Heavy-Duty, individually adjustable power output for up to 4 heaters.
  • Temperature Sensing control for 2 of the 4 heater ports.
    • Heaters are only powered when the temperature of your optics reaches the level you choose. It works on the difference between Ambient Air Temperature and the temperature of your optics. Choose a setting that is 0-10 C°
    • Prevents unnecessary over-heating which degrades image quality
    • Saves battery power
  • Built-in 8V DSLR Power Supply. Just add our DSLR Battery Adapter and power you DSLR from the Dew Controller.
  • 2 DC Accessory Ports
    • 1 Port 12V up to 15 Amp output
    • 2nd port programmable for 12V OR 8V (DSLR Camera Power). Up to 1.5 Amp output
  • 15 Amps total power (max 7 Amp with Cigarette Lighter Plug).
  • Dimmable lights! In fact, after 2 minutes, they shut-off! Pressing 1 of the 2 control buttons will "wake-up" the lights again
  • Cord Management - Power other devices using the 2 DC Accessory Ports. For example, the 12V USB Hub.
  • Low Voltage Cut-Off - A Kendrick Standard that saves your battery from permanent destruction.
  • NEW>> Disable Low Voltage Cut-Off. We don't recommend it, but if you want to drain your battery beyond repair it is now possible.
  • Reverse Polarity Protection

Sensors included: 1 Ambient Air Temperature and 1 Optic Temperature Sensor. Additional Sensors are optional. Also available are Canon and Nikon battery adapters for continuous 12 volt camera operation.

DigiFire 12 DSLR Battery Adapters

DSLR Adapter   Camera Model Number
KDRDSLRC1D   Canon 5D, 10D, 20D, 20DA, 30D, 40D, 50D Digital Rebel
KDRDSLRC2D   Canon 450D, 500D, 1000D, Rebel XSi, 450D, T1i
KDRDSLRC3D   Canon 1100D, T3
KDRDSLRC4D   Canon T2i, T3i, T4i, T5i, 550D, 600D, 650D, 700D
KDRDSLRC5D   Canon 6D, 7D, 60D, 60Da, 70D, 5D Mark II, 5D Mark III
KDRDSLRND   Nikon D600, D610, D750, D800, D800E, D810/A, D7000, D7100, D7200, Nikon 1V1

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Kendrick Standard Dual Channel Controller (KDRSDCC)

This controller replaces the original, long standing Model VI controller. The Standard Dual Channel has a ton of new features but is really simple to use! As well, it can handle more power and use that power more efficiently!

Features & Specifications:

  • Rugged Plastic Case with modern styling.
  • Zero to 100% heater control.
  • Fused onboard. Auto Reset.
  • On board protection from over current, over temperature, over voltage.
  • LED overcurrent indication at both outputs.
  • 10 amp capacity (5 amps per channel).
  • 6' detachable fused Power cord. Cord is fused at 7 amps.
  • Reverse polarity protected.
  • On/off switch (no other dew controller on the market has this).
  • RFI (radio frequency interference) free. A critical feature for astro imagers!
  • Pulse Width Modulation duty cycle control.
  • 4 outputs, 2 for each control knob.
  • LED Power on indicator for both outputs.
  • Low voltage cut-off control with LED indication (a Kendrick standard!). IMPORTANT NOTE on this feature.
  • Mosfet transistors built on board and on EACH output (no voltage drops!). Get the best possible performance out of your heaters!
  • Velcro attachment. Parts included.
  • 12 VDC operation.
  • Dimensions: 4" x 3" x 1.35" (1.75" with knobs).
  • 1 Year warranty

Standard Dual Channel Controller Manual (PDF)


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Kendrick Micro-D Controller (KDRMD)

The Micro Controller is designed for Astronomers and Astrophotographers who want the best in lightweight, compact, Grab'n'Go gear.

Despite its small size, this controller is not small in its performance or build quality. It is well built and well thought out.

The controller has two slotted tabs that can be used to attach the supplied lanyard so that the controller may be hung from a convenient location. Velcro tabs are also provided if you prefer to "stick" the controller to your telescope or mount. Also, the mounting tabs are convenient for anyone who wants to mechanically mount the controller with screws to a Dobsonian telescope base, Dobsonian upper tube assembly, inside an eyepiece box or wherever else one may wish to mount the controller.

TECH SPECS for the Micro-D Controller:

  • ELECTRICAL SPECS: 12 VDC, 3 amps.
  • Single channel, one RCA output for heater attachment.
  • One output at 8 vdc for powering a DSLR camera. Connector is a 5.5mm x 2.5mm DC Power Jack. Requires the purchase of one of our DSLR power Couplers (Canon & Nikon cameras)
  • Simple rotary knob control.
  • LED Power status indication.
  • Low voltage cut-off control. (a Kendrick standard!). IMPORTANT NOTE on this feature.
  • RFI Clean. A must for CCD imagers!
  • Pulse Width Modulation duty cycle control.
  • Reverse polarity protected (a Kendrick standard!).
  • Fused on board with Auto Reset. (the provided power cord is fused as well at 7 amps)
  • Mating Terminal Block power input. This will allow users to terminate the controller power cable in a connector of their choice.
  • Fused power cable included (cigarette lighter plug).
  • Weight: 1.6 oz (30 grams)
  • Dimensions (excluding tabs): 65mm x 36mm x 25mm (2.56" x 1.4" x 1.0")
    (including tabs): 80mm x 36mm x 25mm (3.15" x 1.4" x 1.0")

IMPORTANT NOTE: Micro-D Controller is designed as "light-duty". It is very compact and light weight... perfect for "grab & go" using small batteries. It is NOT designed to run large heaters. Suitable applications include:

    • Small refractors up to 4" diameter
    • Camera lenses
    • Eyepiece heaters

Micro-D DSLR Battery Adapters

DSLR Adapter   Camera Model Number
KDRDSLRC1   Canon 5D, 10D, 20D, 20DA, 30D, 40D, 50D Digital Rebel
KDRDSLRC2   Canon 450D, 500D, 1000D, Rebel XSi, 450D, T1i
KDRDSLRC3   Canon 1100D, T3
KDRDSLRC4   Canon T2i, T3i, T4i, T5i, 550D, 600D, 650D, 700D
KDRDSLRC5   Canon 6D, 7D, 60D, 60Da, 70D, 5D Mark II, 5D Mark III
KDRDSLRN   Nikon D600, D610, D750, D800, D800E, D810/A, D7000, D7100, D7200, Nikon 1V1

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Premier Heaters
These heaters have been built to use only as much power as necessary and thereby not waste energy. They have sponge insulation on one side to prevent heat being dispersed into the atmosphere. The heat is directed into the optics instead. As a result, less energy is needed to keep your optics moisture-free.

The heaters wrap around your objectives, label-side out, and are held in place by elastic/Velcro attachments. The Telrad heaters are held in place with an elastic band. The heaters for secondary mirrors are placed on the backside of the secondary and can be held in place by using the polyester batting found inside the secondary mirror holder. The .965/1.25" 1.25/2" and 2" units are considered eyepiece heaters. The 1.25/2" and 2" are also heaters for camera lenses and certain binoculars.

New in the Premier heater line is the bino-viewer heater. This is comprised of two heaters connecting to one cable, using only one output. These handy heaters come in two sizes: up to 1.5" and 1.5" and over. We currently stock only the bino-heater for 1.5" and larger optics.
Amp Hour Ratings and Fitting Dimensions

Please bear in mind that the following table of amp hour ratings is to be considered accurate only if the controller is set at high. Under normal operating, conditions these ratings can be reduced by 40% to 60% as the normal controller setting is medium to low. This table will also help you determine which heater is right for your scope.
Our Part # Heater Size AP Scope Product Description Amp Hour Rating
KDRTEL Telrad   for Telrad .4
KDR965 .965"   for .965" eyepieces and finder scopes .2
KDR125 1.25"   for 1.25" eyepieces .2
KDR002 2"   for 2" eyepieces, 50mm finder scope objectives, and camera lenses .3
KDR003 3"   fits 90mm-130mm OD (3.5" - 5" OD) .8
KDR004 4" 90EDFL, 92F7EDF, 105EDFS, 105EDT fits 130mm-145mm OD (5" - 5.5" OD) .9
KDR005 5" 130EDFGT, 130GTX, 130EDFS, 130EDT fits 140mm-165mm OD (5.5" - 6.5" OD) 1.2
KDR006 6" 140EDF27, 140EDF4, 155EDF, 155EDFS, 160EDF fits 165mm-200mm OD (6.5" - 8" OD) 1.4
KDR7/8 7"/8" 180EDF, 180EDT, 175EDF fits 200mm-250mm OD (8" - 9.5" OD) 1.5
KDR910 9"/10" 206EDF fits 250mm-310mm OD (10" - 12.5" OD) 1.9
KDR011 11"   fits 310mm-340mm OD (12.5" - 13.5" OD) 2.3
KDR012 12" Riccardi-Honders fits 340mm-400mm OD (13.5" - 15.5" OD) 2.6
KDR014 14"/16"   fits 400mm-460mm OD (15.5" - 18" OD) 4.1
KDRB20 Binoviewer Heater 1.5" and up   for eyepieces with barrel diameters over 1.5" .6

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Due to the cyclical nature of the duty cycle, it is best to power your dew removal controller from its own power supply to avoid the resetting of your mount and keypad. We recommend a deep-cycle, 12 amp hour rechargeable battery for this system at minimum. If you are using household current, it must be transformed to 12vDC with the transformer appropriately rated for your amp requirements.

Astro-Physics offers an AC power converter if you wish to use your your household current. Please review the information regarding the 13.8 Volt, 5-Amp Regulated Power Supply with Cigaretter Lighter Receptacle (PS138V5A).
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Some information on this page was provided by Kendrick Astro Instruments.
Copyright ©2012, Astro-Physics, Inc. - All Rights Reserved

Astro-Physics, Inc.
11250 Forest Hills Road, Machesney Park, IL  61115, U.S.A.
Phone: 815-282-1513   Fax: 815-282-9847