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HI-REZ Marquee LVPS filament and fan mods.

The Filament Modification:

HI-REZ has completely redesigned the filament voltage regulation section of the Marquee LVPS. With this mod, the filament voltage is held at 6.3 volts +/- 50 mV over time and temperature. Further, the new, low-noise +voltage regulator IC in the filament section operates at less than 10% of its rated power at the highest measured temperature within the power supply. This dramatically reduces the possibility of drift or failure
when compared to the original circuit.

The filament voltage is set with precision fixed resistors rather than a trim-pot to further increase the long-term accuracy of the output voltage. The circuit also includes new, low ESR output filtering that eliminates all possibility of oscillation on the output voltage.

In addition, a separate new fail-safe section assures that, even should the voltage regulator IC fail in shorted ode, the filament output voltage will be held to a safe maximum of 7.3 volts. The HI-REZ filament voltage modified VPS comes with a 5-year warranty against CRT failure due to filament over-voltage.

The Fan Modification:

The two small fans in the original Marquee LVPS run quite fast, creating a high level of rushing noise. They also run independently and unsynchronized, which produces an additional variable frequency hum. Previous mods, which moderately attenuate the noise, have used selected, lower noise fans and/or reduced airflow fans. owering the airflow through the LVPS is dangerous since several of its components already run at very high temperatures.

The HI-REZ mod uses a single, much larger fan coupled to the LVPS by a noise dampened, custom-designed lenum. This actually pushes more air through the LVPS than the two original fans while dropping the noise by about 10 dB and totally eliminating the twin-fans' variable hum. The extension of the plenum from the side of the LVPS also brings the new fan's intake closer to the HVPS, thus drawing more cooling air through it.

The Deal:

For $295, HI-REZ will install either modification in a customer supplied working LVPS, completely clean and test the LVPS, and ship it back, by UPS or Fedex ground, anywhere within the continental USA. For an additional $100, both modifications will be installed at the same time.