Grundig TK 220

The Grundig TK 220 (also known as TK220 Automatic or TK 220 de Luxe in some variants) is a mid-1960s open-reel (reel-to-reel) tape recorder produced by Grundig Radio-Vertrieb in Fürth, Germany. Manufactured primarily from 1964 to around 1967, it was a compact, mid-range mono domestic machine aimed at home users and hobbyists seeking reliable performance with dual speeds and a 7-inch reel capacity.

The TK 220 was priced originally around £50–70 in export markets (equivalent to roughly 500–700 DM in Germany), positioning it as a solid mid-tier option in Grundig's TK series. It was valued for its push-button operation, automatic features in some variants (e.g., level control), and decent sound quality for dubbing radio broadcasts, family recordings, or basic music.

Key Technical Specifications

Track System: 2-track (half-track), single-channel monaural (monaural record/playback; records on upper half of tape in one direction, lower half in reverse)

• Tape Speeds: Two speeds — 9.5 cm/s (3¾ ips) and 19 cm/s (7½ ips); switch-selectable (higher speed for improved fidelity and detail)

• Reel Size: Maximum 7 inches / 18 cm (standard domestic capacity; supports NAB/international hubs)

• Heads: 2 heads — combined record/playback head + erase head (permalloy construction; no separate playback head or off-tape monitoring)

• Motors: 1 motor (capstan drive; single-motor design with mechanical reel assistance; reliable induction-type motor typical of mid-1960s consumer machines)

• Drive System: Mechanical transport with push-button controls; constant tape speed; foil-sensing automatic stop at tape end; basic tension regulation suitable for standard and thinner tapes

• Frequency Response: Approximately 50–14,000 Hz (at 7½ ips; respectable for a dual-speed mono recorder of the era, with good clarity and extension for voice and music)

• Signal-to-Noise Ratio: ≈45–55 dB (typical; good for mid-1960s consumer mono, aided by quality circuitry)

• Wow & Flutter: ≈0.2–0.3% (acceptable for domestic use; single-motor designs had tolerable variations)

• Equalization: CCIR/European standard for the period (some export versions note NARTB compatibility)

• Inputs:Microphone: Low-level (dynamic mic via DIN or proprietary socket; often supplied external mic)
  Line/Radio: High-level input via DIN connector (Grundig 5-pin standard)
  Phono/Grammophon: Additional high-level input for record players
  

• Outputs: Built-in loudspeakers (2 loudspeakers in some variants for improved dispersion); line out via DIN socket; output power ≈4 watts

• Power Supply: Alternating Current (AC) mains — 110; 130; 220; 240 V (multi-voltage taps for export); power consumption around 55–80 W; no battery option (mains-only domestic/portable hybrid)

• Dimensions: Approximately 410 × 200 × 340 mm / 16.1 × 7.9 × 13.4 inches (W × H × D) — compact suitcase/portable form factor with handle

• Weight: Around 10–12 kg (22–26 lbs) — portable yet substantial due to metal chassis, transformers, and tubes

• Electronics: Valve/tube-based (typically 5 tubes; common complement includes EF86 preamp, ECC81 phase splitter/driver, EL84 output (push-pull), EM84 magic eye level indicator; metal rectifier for power supply)

• Other Features: Magic eye (EM84) recording level indicator (glow for level monitoring); mechanical tape counter; automatic tape-end stop; pause function; recording time ≈60–120 minutes total (depending on speed and tape thickness) on 7-inch reels with standard tape

Design and Performance Notes

The TK 220 was a practical mid-range domestic recorder with a focus on versatility and sound quality: dual speeds provided flexibility—7½ ips for higher fidelity (better transients and extension) on shorter reels, and 3¾ ips for longer runtime. The tube circuitry delivered a warm, musical tone suitable for radio dubbing or home entertainment, with improved frequency response over earlier single-speed models—modern vintage ratings place it around 6–7/10 for sound (solid mono performer) and 7–8/10 for build reliability/durability.

The drive mechanism was durable and straightforward, with minimal electronics complexity. Common long-term service needs include:

• Tube replacement/check (EF86 microphonics; EL84 output wear)

• Cleaning heads, capstan, pinch roller, and tape path

• Replacing electrolytic capacitors (leakage common after 60+ years)

• Lubricating mechanisms and checking drive belts/pulleys

• Magic eye alignment and rectifier checks

Historical Context

The TK 220 was part of Grundig's foundational 1950s–1960s TK series that popularized open-reel recording in Europe and export markets. It followed models like the TK 20–TK 25 and preceded later multi-speed/stereo machines (TK 14x, TK 24x, etc.). Surviving examples are collectible today, often in good cosmetic condition due to sturdy construction, but most require tube and capacitor restoration for reliable operation. They represent an accessible entry into vintage tube-era open-reel collecting, especially for those interested in mid-1960s German audio engineering and dual-speed mono designs.