Used ICs: CX 0168, TBA 820M, LA4550, LA7343, LA1260, LA1160
CCE 930D schematic
Used ICs: AN7205, BA1442A, LA4598, BA1313L
TEAC A 6100 SCHEMATIC
National Panasonic RQ 92 schematic
Used ICs: AN6558F, AN6552, MN3007, BA3702, TA7240AP
Vintage Cassette Radio Recorder – National Panasonic RQ 432S schematic, layout and dial cord setting.
The main fault that can occur to this set is the tuning drift as climatic change. The inductance of TR54 and or TR56 changes. Replace them if this type of fault occurs.
At the amplifier stage, C19 and C20 [capacitors connected between collector base of the output transistors] may get leak. Resulting distorted audio output. They have used steroflex capacitors there. I’ve replaced both of them with disc ceramic [250VDC] type, and going fine.
The C34 [1000MFD-10V] should be checked for its capacitance. It is best to replace it. Sound distortion can occur if this capacitor is damaged.
C32 [220MFD 10V] can also be problematic. Replace it.
I own this model set, which bought at mid of 70s, I presume, is working fine till time. There is no more problems can occur to this set.
Amplifier section schematic
Used
ICs: TA7358AP, TA7343P, TA7757P, TA7233P, TA7668BP, TA7233P, TA7343P
Dial cord restringing
Tight up the dial cord for the designated length, and cement after two ties.
Hook the dial cord to the spring and pass through the opening of the drum from the inside.
Turn the variable capacitor fully clockwise and mount the drum onto it.
[to prevent the variable capacitor from damage, slightly return it in the opposite direction and fasten the dial cord.]
Wind the dial cord in numerical order as illustrate.
Turn the variable capacitor fully counterclockwise and set the pointer to the “0” position in the dial scale.
Wiring diagram
Schematic
Mechanism exploded view
Cabinet exploded view
BS-72 – CD-PLAYER – RADIO - CASSETTE COMBO - BRITANIA - Circuit Diagram _ Exploded view
Philips AZ1010 – CD Radio Cassette Recorder – Circuit Diagram
Sanyo MCD ZX700F Circuit diagram – Bassxpander
