{"product_id":"155463","title":"300555","description":"\u003cp\u003e1978 MODEL 30 DIGITAL PANEL METER - 2V F.S. RANGE - 5VDC POWERED - NOS W\/ ORIGINAL BOX AND INSTRUCTIONS AND SCHEMATIC - The actual red 7-segment digits on the face of the meter are monolithic optoelectronic chips manufactured by Fairchild's pioneering Microwave and Optoelectronics division - Fairchild FND500 \/ FND507 series (or multi-digit equivalents like the FND5148). These are Common Cathode (or Common Anode depending on the driver chip pairing), single-digit GaAsP (Gallium Arsenide Phosphide) red LED displays. They are highly distinct because they use tiny, bright red LED dice bonded directly inside a standard DIP-style package - Inside the meter, an analog-to-digital converter (ADC) circuit outputs a Binary Coded Decimal (BCD) signal. This signal is sent to the 9317\/7447 decoder chips, which decode the binary number into 7 distinct paths. Those paths travel through a network of current-limiting resistors directly into the pins of the FND-series LED blocks to light up the correct segments\u003c\/p\u003e","brand":"FAIRCHILD","offers":[{"title":"Default Title","offer_id":45280110673973,"sku":null,"price":125.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0219\/7936\/5440\/files\/AP1GczOMm3fZzBd8Kv36PB1BBONyv_-8m8FIRGkAw613LD1Qsq7A-rjNQSBBG2Wvf9_xRcumjy1UsUzbIzB1SIjrYgDHk7NoxfLVxO91daH8suvB3ky-D_SZ6TUYq1djidtSDlfQfXn6mVZweEKYqRE3vbE6Jg_w1907-h1907-s-no-gm.jpg?v=1780621220","url":"https:\/\/greenbrookonline.com\/products\/155463","provider":"Green Brook Online","version":"1.0","type":"link"}