Philips EL3585

The Philips EL3585 (including variants like EL3585/00, /15, /22, /30, or export rebrands such as Norelco Continental 100, RK5, or Maestro 10) is a pioneering early 1960s portable battery-powered reel-to-reel tape recorder, introduced around 1961 (service manual dated July 1961) and produced through the mid-1960s (some sources cite up to ~1964). It was one of the first truly portable, all-transistor reel-to-reel machines using standard flashlight batteries, designed for field reporting, dictation, interviews, or casual home use—often called a "reporter" or "twin-track" recorder.

This compact, lightweight unit marked an important step in portable audio before the compact cassette (also Philips-invented in 1963) took over. It competed with emerging pocket recorders but offered open-reel flexibility and better tape handling for the era.

Key Technical Specifications

• Recording/Playback System — Half-track (two-track) mono; records and plays in one direction (forward only; reverse by flipping tape manually); full-track mono head configuration in some descriptions, but primarily half-track for compatibility.

• Tape Speeds — Single speed: 1⅞ ips (4.75 cm/s). (Optimized for long-duration recording on small reels; no multi-speed capability.)

• Reel Size — Maximum 4 inches (10 cm or ~100 mm) diameter (some sources note 3–4" comfortably; smaller than standard 5–7" consumer reels).

• Frequency Response (approximate, within ±3 dB as per period specs):120 Hz – 5,500 Hz (realistic for slow-speed portable on consumer tape; speech-oriented, limited highs).
  

• Wow & Flutter — Less than 0.5% (acceptable for battery/portable single-motor design; belt-driven stability when fresh).

• Signal-to-Noise Ratio — Not precisely specified, but typical early transistor portable ~35–45 dB (decent for voice/journalism use).

• Heads — 2 heads: combined record/playback (permalloy) + erase head.

• Drive System — Single DC motor (battery-powered); belt drive to capstan/flywheel; simple mechanics with push-up/push-down controls (often visible under transparent lid); mechanical brakes; fast wind/rewind limited (e.g., ~15 seconds for small reels in some tests).

• Electronics — Fully transistorized (germanium types; typically 6 transistors: OC75 ×3, OC71, OC72 ×2 in base /00 model; later variants like /15 used OC75N and OC70 diode replacements); printed circuit board amplifier.

• Amplification & Speakers — Built-in mono amplifier; permanent magnet dynamic (moving coil) loudspeaker; low output power (~1–2 W); basic volume/tone controls.

• Inputs — Microphone (DIN terminal, low-level; often supplied with dynamic mic like EV 7016/20 in related models); possible line in limited.

• Outputs — Internal speaker; DIN for external amp/headphones (limited); monitoring while recording possible.

• Features —Push-button/push-up controls (record, play, rewind, fast forward, stop).
  VU meter/level indicator (some variants).
  Transparent protective cover over mechanism/controls.
  Portable design with leather carrying case option.
  Optional AC mains adapter (e.g., separate EL3766 PSU for home use).
  No auto-reverse or advanced editing.
  

• Power — Battery: 6 × 1.5 V (D cells / LR20; total 9 V); optional AC mains via external supply (EL3766 or similar). Low consumption for extended field use.

• Build & Dimensions — Compact plastic case (often grey/beige); approx. 265 × 190 × 95 mm (10.4 × 7.5 × 3.7 inches); weight ~1.8–2 kg without batteries (very portable for era).

• Manufacturing — Primarily Belgium (Hasselt Philips facility) or Netherlands (Eindhoven); variants produced regionally (e.g., Germany as RK5).

Performance & Legacy Context

The EL3585 excelled as a rugged, battery-operated portable for journalists, students, or travelers—up to ~2 hours recording/playback on long-play tape with 4" reels (e.g., 2×45 mins double-play). Sound quality suited speech/voice (clear but limited bandwidth at 1⅞ ips), with surprisingly good reliability from transistors (no tube heat/filament issues). It was not hi-fi (no 7½ ips or stereo), but practical and ahead of its time in portability.

It influenced later portables and indirectly the cassette push (its success in Hasselt spurred cassette development). Variants like Norelco Continental 100 appeared in North America.

Common issues today: Belt/pulley degradation (Philips rubber turns to goo/tar—messy clean/replace), electrolytic capacitor drying, germanium transistor aging/leakage, dirty heads, battery corrosion (if stored with cells), and mechanical wear on controls. Restorations focus on belts (modern equivalents available), recap, cleaning, and alignment. Service manuals exist (e.g., 1961 dated PDF on KevinChant.com, Elektrotanya, AudioCircuit.dk; HiFi Engine has user manual).

Compared to series siblings:

• EL3586 (1964+): Similar portable but often AC/battery hybrid with slight upgrades.

• Earlier EL35xx: Mostly mains-powered, larger reels/speeds. The EL3585 stands out as an early all-battery, all-transistor open-reel portable.