Operation
Taylorbrite's dimming system uses a technique known as Pulse Group Modulation, or PGM. CCF lamps are best excited by AC voltages in the 20kHz to 50kHz range. The ideal wave shape is a "sine" wave, similar to the AC voltage wave shape found at a typical wall outlet. This wave shape is preferred because it generates the least amount of radio frequency interference (RFI). For the purposes of this discussion, we will refer to one cycle of the sine wave shape as a 'pulse'. Since the frequency of these pulses is fixed, say at 20kHz, then one pulse will occur every 50uS (1/20,000 second). This is very fast. So fast that if we were to remove one pulse, the eye would never notice it, right? Not exactly. In fact, the brain will average the pulses of light and will cause us to 'see' a brightness level lower than what we normally perceive to be full-on.

The process of removing pulses from groups is called "Modulation". Hence the term PGM means 'removing pulses from groups'. As long as the pulse removal process continues to occur fast enough, the eye and brain will continue to average the result. Very effective dimming can be obtained down to 1% of full brightness!

In order for this system to function, the lamp's power supply must be designed to implement this modulation technique. Consequently, a third wire is supplied for the modulation control signal. This signal is generated by the Taylorbrite dimmer module.

Benefits
The true benefit of this system is the ability to dim efficiently, without generating heat. Furthermore, dimming does not impede the life of the electrode, nor does it create RFI. Because a "signal" is sent from the dimmer that alters the frequency of the sine wave, power draw of the CCF lights is reduced in proportion to the light output. This is ideal for maintaining battery capacity at night, when full brightness is not necessary, but a slight amount of light may be desired.