This part is a kind of semiconductor called BL3208B.

Function of this product has 2048-stage low voltage operation and low noise BBD variable delay line in audiofrequency range.

Manufacturers : SHANGHAI BELLING

Image and pinout :

Some of the text within the PDF file :

BL3208A/B 2048-Stage BBD Description The BL3208A/B is a 2048-stage low voltage operation, and low noise BBD variable delay line in audio frequency range. The device operates on +5V to +10V supply and provides a signal delay up to 102.4ms.The BL3208 contains 3208A and 3208B two classes. The only differences between them are the outlook and pin assignment. Pin Assignment GND CP1 IN VGG DIP 8 PIN GND CP 2 BL3208B OUT 1 OUT 2 DIP 8 PIN CP 1 VDD VGG IN BL3208A OUT 2 OUT 1 CP 2 VDD Features ¡ñ ¡ñ ¡ñ ¡ñ ¡ñ ¡ñ ¡ñ ¡ñ Adjustable audio signal delay time range: 10.24ms102.4ms Wide supply voltage range: 5V-10V Typical insertion loss: Li=0dB Wide dynamic range: S/N=71B(type) Low distortion: THD=2.5%(type) Clock frequency range: 10kHz-100kHz N-channel silicon gate p [ ... ]

BL3208B PDF Datasheet Download