The GRUNDIG TK 20 Tape Recorder is simple to operate. It operates on twin tracks at a speed of 3 3/4 ips. This unit allows for reusal of tape through erasing recordings, and the old recording is automatically wiped out with each new one. This tape recorder can be used on 50 or 60 cps AC mains with voltages of 117, 200, 220, and 240. Recordings are played back by first sending the tape back to its original spool, then once the recording is ready to be played back it is heard through the unit's internal loudspeaker.
The GRUNDIG TK 46 Tape Recorder is deemed the all purpose stereo tape recorder, rated as one of the outstanding tape recorders in the world in its day. It records and plays back both mono and stereo. It is a four-track recorder and has three tape speeds: 1 7/8, 3 3/4, and 7 1/2 ips. It uses 7 inch reels, and has up to 16 hours of recording and playback time. It features 3 separate heads, to erase, record, and playback or monitor the recording. It can be used on 50/60 cps with 110-240 volt AC.
The GRUNDIG TK 200 Tape Recorder is designed for home and family recordings. It has two speeds, 3 3/4 and 7 1/2 ips. The system has dual tracks and uses 7" reels. It has a recording and playback capacity of up to 4 hours, with a built in "lock" that minimizes the chance of accidental erasure during a recording. Recordings can be played back through the famous GRUNDIG permanent dynamic hi-fi speaker, or through an external speaker with the use of a connecting jack.
The GRUNDIG TK 830 Tape Recorder has two speeds: 3 3/4 and 7 1/2 ips. The faster speed (7 1/2 ips) is designed to be used with the Dynamic Microphone for high quality musical recordings, while the slower speed (3 3/4 ips) is more suited towards recordings that do not need to be of such a high caliber, such as speeches or radio plays. The slower speed allows for an extra hour of recording and playback time, as each one of the dual separate tracks runs for 30 minutes at the faster speed and 60 minutes at the slower speed. This tape recorder is regarded as being suited for setting amateur films to music.