Technical Details
Brand: Philips
Model:N4520
Category:Super High Fidelity
Application:Semi-Pro
Electronics:Solid State
Equalization:NAB , IEC
Country of Manufacture:Netherlands
Release dates:1978 - 1983
Tracks:1/4 Rec/PB
Speeds: 3 3/4, 7 1/2, 15
Max Reel Size("): 10.5"
Number of heads: 3
Dimension: 20.8" x 20.7" x 9" - 530 x 527 x 230mm
Head Composition: Glass
Head Configuration: Stereo
# Motors: 3
Auto Reverse?:No
Voltage(s): 110-120v, 220-240v, Multi
Outputs: RCA, DIN
Frequency Response:30Hz to 26kHz at 15 ips - 30Hz to 22kHz at 7.5 ips
Wow and Flutter:.035 at 15 and 7.5 ips
Signal-to-Noise Ratio:64 db
Sound quality rating:8 / 10
Long-term reliability rating: 8/ 10
Weight: 55.5 Lbs - 25 kg
Additional Details
Description
The Philips N4520 and 4522 were the best consumer R-R tape recorders Phillips ever produced, featuring three motors, three heads and good enough to be semi-pro machines. The electronics were of a very high standard, making these tape recorders contenders against the best from Japan and some of the other European producers. The transport was very similar to that of the Revox A700. Three speeds (3¾ , 7½ and 15 ips) were provided and 10½ ” NAB spools accepted. The electronics were of a very high standard, putting this recorder very much into the semi-professional category.
Features
IEC / NAB equalization settings with adjustable bias
Long life FSX heads- Wedge shaped & hyperbolically ground record and playback heads. Ferrite Erase head with double gap
5 digit fluorescent tape counter calibrated in minutes and seconds with a zero stop option
Variable wind speed so you can store your tapes correctly
Peak hold setting for VU meter
All metal reel locks for long-term durability
Headphone volume control
Additional Info
Wow & flutter (DIN)
3¾ ips: .055/.057%
7½ ips: .034/.038%
15 ips: .034/.042%
Rewind speed: 2minutes 40s for 10½ inch 3600ft reel
Half Track (4522) or quarter-track (4520) stereo versions
3 mm. thick aluminum front panel
/ Inputs (sens / clipping): mic: 290uV / 222mV (-58.6dB noise) line: 93mV / 6.3V DIN: -25dB / >26dB (18.3kohm impedence) / Maximum line output: 675mV
Potential service issues for these older machines
Power switch should probably be replaced as they have a reasonably high rate of failure and will require some minor customizing to the existing mounting bracket
The capstan speed regulator chip Is of an old variety and should be replaced with a more modern IC
The shafts on the idler pulleys (with the rubber tire) have been known to break, but not overly common
The assembly for the tape lifters (rewind and fast-forward) should be cleaned and re-lubricated
Replace 19 transistors on the mainboard (Source)
7x BF245A : TS2 TS5/TS105 TS4/TS104 TS3/TS103 1x BC547 : TS11 4x BC548 : TS8 / TS108 TS9 / TS109 2x BC549 : TS1/101 1x BC557 : TS10 2x BC546A : TS6/106 2x BC556A : TS7/107