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Bandridge VA-315

Front Panel
Front Panel

This is a small audio mixer, marketed for camcorder audio dubbing.

Rear Panel
Rear Panel

I/O Panel on the rear of the unit. Contains a small preamp, but will not drive speakers directly. Power is a 9v battery or plugpack.

PCB Front
PCB Front

Front of the PCB removed from the case. Mic preamp bottom right corner. Each channel has it’s own Preamp IC between the faders.

PCB Rear
PCB Rear

Rear of the PCB.

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Southwestern Bell Freedom Phone

Phone
Phone

This is an old cordless landline phone, with dead handset batteries.

Handset Radio Board
Handset Radio Board

Here’s the handset with the back removed. Shown is the radio TX/RX board, underneath is the keyboard PCB with the speaker & mic. All the FM radio tuning coils are visible & a LT450GW electromechanical filter.

Handset Radio Board Bottom
Handset Radio Board Bottom

Radio PCB removed from the housing showing the main CPU controlling the unit, a Motorola MC13109FB.

Keypad Board
Keypad Board

The keypad PCB, with also holds the microphone & speaker.

Handset Keypad Board Bottom
Handset Keypad Board Bottom

Bottom of the keypad board, which holds a LSC526534DW 8-Bit µC & a AT93C46R serial EEPROM for phone number storage.

Base Main Board
Base Main Board

Here’s the base unit with it’s top cover removed. Black square object on far right of image is the microphone for intercom use, power supply section is top left, phone interface bottom left, FM radio is centre. Battery snap for power backup is bottom right.

Power Supply Section
Power Supply Section

PSU section of the board on the left here, 9v AC input socket at the bottom, with bridge rectifier diodes & main filter capacitor above. Two green transformers on the right are for audio impedance matching. Another LT450GW filter is visible at the top, part of the base unit FM transceiver.

ICs
ICs

Another 8-bit µC, this time a LSC526535P, paired with another AT93C46 EEPROM. Blue blob is 3.58MHz crystal resonator for the MCU clock. The SEC IC is a KS58015 4-bit binary to DTMF dialer IC. This is controlled by the µC.

Base Main Board Bottom
Base Main Board Bottom

Underside of the base unit Main PCB, showing the matching MC13109FB IC for the radio functions.