I have fully recapped, ‘pinned’, and recalibrated a Sansui QRX-9001 which --along with four Axiom’s-- remains a prideful pace as my primary listening unit. Needless to say, I’ve also become skilled in putting pigtails on fuse lamps to replace the Sansui unobtanium Dial and Tuning Meter light bulbs. From time to time, I’ve also had to do the near equivalent of laparoscopic surgery to replace burned out Power Meter bulbs.
After one lamp replacement too many, I decided to look at completely relamping the unit with LEDs. However, a key criteria was to retain the 1970’s Sansui vintage ‘look’ and to keep the conversion reversibly straight forward. The resulting QRX-9001 LED relamping has very nice (I personally would say beautiful) emerald green Dial and Tuning Meters and ‘incandescent’ looking Power Meters.
As described in the attached uploaded pdf, this began with a fairly extensive investigation of the available colored and white LEDs and developing how to determine suitable units. The resulting two-part QRX LED Lighting Instructions Drawings Photos.pdf starts by explaining how to use www chromaticity tools with manufacturer’s color nanometer and XY specifications to select suitable LEDs for pretesting and relamping use. These were coupled with a specific low-differential-voltage regulator to develop an Addon Board to supply the necessary AC to DC conversion.
Included in the pdf is a complete parts list plus four key Sansui QRX installation photos, as well as detailed drawings for the Addon Board and the various Tuning Meter, Dial Lighting, and Power Meter LED conversion assemblies. Extensive step by step instructions are also provided for constructing both the assemblies and for actually doing the complete relamping.
The end result is a Sansui QRX with a very attractive emerald green Dial and Tuning Meter lighting as well as relatively incandescent looking Power Meter lighting. Moreover, these LEDs produce very little heat and won’t burn out causing inconvenient replacements.
Furthermore, because of the way this LED lighting conversion is accomplished, these concepts, LED selections, and Addon AC-to-DC Board should also be potentially applicable to other Sansui units and even to other manufacturer’s units of the 1970s.
I might add that it took far less time to do this QRX-9001 LED relamping; than it did to write it up here.
Regards,
dickmc
After one lamp replacement too many, I decided to look at completely relamping the unit with LEDs. However, a key criteria was to retain the 1970’s Sansui vintage ‘look’ and to keep the conversion reversibly straight forward. The resulting QRX-9001 LED relamping has very nice (I personally would say beautiful) emerald green Dial and Tuning Meters and ‘incandescent’ looking Power Meters.
As described in the attached uploaded pdf, this began with a fairly extensive investigation of the available colored and white LEDs and developing how to determine suitable units. The resulting two-part QRX LED Lighting Instructions Drawings Photos.pdf starts by explaining how to use www chromaticity tools with manufacturer’s color nanometer and XY specifications to select suitable LEDs for pretesting and relamping use. These were coupled with a specific low-differential-voltage regulator to develop an Addon Board to supply the necessary AC to DC conversion.
Included in the pdf is a complete parts list plus four key Sansui QRX installation photos, as well as detailed drawings for the Addon Board and the various Tuning Meter, Dial Lighting, and Power Meter LED conversion assemblies. Extensive step by step instructions are also provided for constructing both the assemblies and for actually doing the complete relamping.
The end result is a Sansui QRX with a very attractive emerald green Dial and Tuning Meter lighting as well as relatively incandescent looking Power Meter lighting. Moreover, these LEDs produce very little heat and won’t burn out causing inconvenient replacements.
Furthermore, because of the way this LED lighting conversion is accomplished, these concepts, LED selections, and Addon AC-to-DC Board should also be potentially applicable to other Sansui units and even to other manufacturer’s units of the 1970s.
I might add that it took far less time to do this QRX-9001 LED relamping; than it did to write it up here.
Regards,
dickmc
