Panasonic RX-1650LS 4 Band Radio Cassette Recorder /Boombox/ (1980) Part 1 Repair

Vintage Boombox a Panasonic-tól 1980-ból.
Tisztítva-átnézve-javítva.
Keleti OIRT normás 65-74 MHz-ig, a 80-as évek-ben még Magyarországon is keleti norma volt így az akkori adókat jól fogta, mivel Magyarországon forgalmazott termék volt, a tulajdonos nem kérte az áthangolást nyugati CCIR normára hagy maradjon eredeti állapotban, de 2-3 adót így is lehet hallgatni rajta.
Magyarországi használathoz átkapcsolva 240V-ra.
Made In Japan.

Panasonic RX-1650 LS radio tape recorder. Manufacturer: Matsushita Electric Trading Co. Ltd., Japan.

The device is equipped with a mono radio section suitable for long-, medium-, short- and ultra-shortwave reception and a cassette tape recorder section suitable for half-band mono sound recording. It has an integrated circuit mono amplifier. With the tape recorder, you can record with the built-in electret microphone and directly from the radio part, as well as from an external program source. It has automatic recording control, its push-button mode switches operate the chassis according to functions similar to the W 1450 model, with so many differences, this one also has a momentary stop function. It also has a counter and tape end switch. Recording mode is indicated by a separate LED located on the radio's station scale next to the station tuning indicator. There are two speakers in the device: a wide-band 10 cm diameter type and a tweeter type with a 5 cm diameter. An external sound box or headphones can also be connected to the output of the amplifier.
Technical data and quality characteristics
Mechanical data

Operating position: horizontal and vertical
Tape storage system: Compact Cassette
Fixable track system: half track, mono
Playable track systems:
half band mono
2 x quarter band stereo
Recording and playback tape speed: 4.76 cm/s ± 2%
Belt speed fluctuation: ± 0.3%
Fast winding time for C 60 cassette: 120 s
Built-in motor: 1 pc, direct current
Tape length measurement: with a three-digit counter
External dimensions: 131 x 225 x 348 mm
Weight: 2.94 kg (without batteries)
Audio frequency transmission characteristics

Usable tape types:
iron oxide (Fe2O3)
ferrochrome (FeCr)
chromium dioxide (CrO2)
Frequency transmission measured from tape:
100...10,000 Hz ± 3 dB (Fe2O3)
100...11,000 Hz ± 3 dB (FeCr)
100...12,000 Hz ± 3 dB (CrO2)
Signal-to-noise ratio measured from tape, at 1 kHz/0 dB signal:
= 38 dB (Fe2O3)
= 40 dB (CrO2)
Cancellation attenuation at 1 kHz/0 dB signal: = 60 dB
Harmonic distortion measured from tape, at voltage output, at 333 Hz/0 dB signal:
= 5% (Fe2O3)
= 3.5% (CrO2)
The frequency range of the final amplifier: 100...12,000 Hz -2 dB
Harmonic distortion of the final amplifier:
At 333 Hz/0 dB signal: = 6%
At 1000 Hz/0 dB signal: = 5%

Operating data

Recording and playback correction:
3180 + 120/70 µs
Frequency of erasing and premagnetizing current: 35 kHz ± 2 kHz
DC supply voltage: 9 V
Operating tolerance of the supply DC voltage: -1.5 V / +1 V
Battery set: 6 1.5 V R 20 goliath batteries
Mains supply voltage: 220 V, 50 Hz
Power consumption from mains: 9 VA
Permitted mains voltage fluctuation: ±10 V

General Informations

Tone control:
±12 dB at 100 Hz
±14 dB at 10 kHz
Audio frequency inputs:
microphone: 1 mV/100 kOhm
turntable: 100 mV/470 kOhm
radio: not connected separately
Audio frequency outputs:
signal voltage: 2 V/22 kOhm (maximum)
headphones: 1.65 V/8 ohms
speaker: 2.19V/3.5ohm
Audio frequency output power:
in plant operation:
1 W/3 ohms (sinusoidal)
1.2 W/3 ohms (musical)
in mains operation:
1.4 W/3 ohms (sinusoidal)
1.6 W/3 ohms (musical)
Built-in speaker:
1 x 3.2 ohm/2 W
1 pc 200 ohm/0.5 W