Dimmer for regulating the flat field box

When adjusting FlatFieldBox (FFB) illumination for astronomical CCD cameras, we need vibration-free and extremely short exposure times in the order of (minus) milliseconds. Unfortunately, conventional dimmers cannot be used for this purpose, but only so-called PWMs with a switching frequency of 25 kHz or even faster!

What is PWM and why do we use it?
Theoretically it would be enough to reduce the voltage via an ohmic resistor if you did not want to attenuate the LEDs but rather the incandescent lamps. However, we absolutely need a dimmer with pulse width modulation that regulates the time interval in which the full voltage is effective: the dimming tool is switched off and on in rapid succession.

Depending on the on/off frequency, different accessories can be activated: for a heating jacket it would be sufficient to turn it on and off once a second, or even less frequently, because its inertia is very high. In everyday life, around a hundred cycles per second are sufficient for LED lights regulated in this way (e.g. living room lighting), because the human eye can hardly notice flickering with a frequency of 25 Hz. FlatFieldBoxes (FFBs), built for astronomical CCD cameras, require at least 25kHz to ensure an evenly illuminated area even in a short illumination period.

Technical data
Input: RCA and 5.5/2.1mm (known polarity: center positive)
Output: RCA and 5.5/2.1mm (known polarity: center positive)
ATTENTION: Connect the dimmer in the right direction, otherwise it will not dim!
Frequency: Over 30 kHz, typical 31-36 kHz (guaranteed to turn on and off more than 30,000 times per second)
Maximum current: 3A
Input Voltage Range: 12-24V
Cable length: with additional cable 230cm (included)
Weight: 130 grams

RCA and 5.5/2.1mm connectors can be used
Due to the different manufacturer specifications of the FlatFieldBox (FFB), we offer a combined solution: both RCA-RCA and 5.5/2.1 - 5.5/2.1 mm connections are possible.

The total length of the connected cables (including the dimmer unit) is approximately 230cm.