SONY TC-4250SD
¥ 59,800 (released in 1973)
¥ 67,800 (around 1974)
Commentary
A cassette deck with a built-in Dolby system.
The head is an F & F head developed by Sony.
This head has an all-ferrite structure that uses the same ferrite for the core and guard parts to prevent the loss of one side due to aging and the collapse of the gap edge. In addition, the head surface is finished with a black mirror to prevent the adhesion of dust.
By using a large 90 mm diameter flywheel in the capstan part of the mechanism part, stable and smooth rotation is realized.
The built-in Dolby System as a noise reduction system reduces the hissing inherent to the tape.
Equipped with a 3-stage switching type tape selector, and also compatible with Duad Ferrichrome cassette.
The Sony Limiter recording method is adopted.
If you turn the limiter switch ON after manually adjusting the level, the limiter circuit will operate only when a large input is suddenly applied, preventing distortion.
It is equipped with a VU meter with lighting and a peak level indicator using LED to respond to large instantaneous inputs that cannot be followed by the VU meter.
Equipped with a memory counter.
Equipped with an auto shut-off mechanism, the operation button and the head pinch roller return to the stop position when the tape is wound in any case such as recording / playback / fast-forward / rewind, thereby preventing stress on the mechanism and the tape.
Equipped with MPX filter.
Since the microphone input circuit and line input circuit are designed independently, mixing recording is possible.
Equipped with line-out volume.
Equipped with a lock type pose button.
Equipped with function display lamp.
There was a dust protector sold separately.
Model Rating
| Type | Cassette deck |
| Tape speed | 4.8cm/sec |
| Track system | 4-track 2-channel stereo |
| Recording time | 120 minutes round trip by C-120 |
| Signal-to-noise ratio | 55 dB (peak level) |
| Distortion factor | 2.0% |
| Frequency characteristic | 20 Hz to 17 kHz |
| Wow and flutter | 0.07% |
| Input jack | My Kujac (standard jack) : Minimum input level 0.2 mv / low impedance Line input jack (pin jack) : Minimum input level 0.06V/100k Ω |
| Output jack | Line output jack (pin jack) : Specified output 0.775V/10k Ω or more Stereo headphone jack : 8 Ω |
| Recording and reconnector | Input impedance : 10k Ω or less Output load impedance : 50k Ω or more |
| Semiconductor used | Transistor : 39 IC : 2 Diode : 2 pcs |
| Pwer | 100 VAC, 50Hz/60Hz |
| External dimensions | Width 411x Height 138x Depth 294 mm |
| Weight | 7kg |
| Sold Separately | Dust Protector DP-24 |