Sensor Transistor and Biasing Trimmer (Beogram 4002, 4004 and 4000)

Beolover Sensor Arm LED Light Source for Beogram 4002/4 and 4000:

• Replaces the sensor transistor and biasing resistor in any Beogram 4000, 4002 and 4004.
• Many original transistors lost some of their gain, which may disable the record detection function. As a consequence the arm may drop on an empty platter. Ouch!!! Replacement ensures that the record detectionj functionality works properly.
• Replacing the original fixed value biasing resistor with a 5MOhm trimmer allows adjusting the bias to meet the gain spec given in the manual (4V at collector)
• Direct drop in replacement. Replaces 1TR3/R26 in DC motor Beogram 4002 (Type 551x/552x), 1TR9/1R33 in AC motor Beograms (Type 550x) and 1TR14/1R33 in Beogram 4000 models.
• Comes with alignment fixture to position LED board in correct location.
• See this Beolover blog post for an introduction to the restoration of the sensor arm and record detection circuit.
• Installation requires soldering/desoldering capability, and potentially requires an oscilloscope for trouble shooting. Some experience with electronics is helpful.