• Freq Response  ?
• Signal to Noise  ?
• Speed turntable 20 rpm
• Motors 1
• Reels  none
• Time will record for 3 minutes
• Weight 22lbs
• Price ?

The recording material in this case is in the form of a 9-inch disc, and the sound track is a spiral running from an inner diameter of 5 inches to the outer edge. The recording track has a width of 0.014 inch, and the pitch of the spiral is 0.025 inch. Despite this close spacing, no noticeable crosstalk can be detected. The powder-coated paper discs can be folded and mailed like an ordinary letter. No guide grooves are provided on the coated discs.The turntable rotates 20 r.p.m., resulting in a total recording time of slightly over 3 min. This instrument deserves special mention because it presently represents the most simple and basically the most inexpensive mechanical and electrical design for a magnetic recorder that has been produced commercially. A single crystal headphone is used both as a recording microphone and as a playback earphone". radiomuseum.org

A reminder that the prices listed are what the item originally sold for in the year it was released.

• Freq Response  ?
• Signal to Noise  ?
• Speed 7.5 ips
• Motors 1
• Reels  7" w/Paper tape
• Timing accuracy
• Weight 42lbs
• Price $367.50

• Freq Response  ?
• Signal to Noise  ?
• Speed  3.75 & 7.5 ips
• Motors 1
• Reels up to 7""
• Timing accuracy
• Weight 42 lbs
• Price 289.50

• Freq Response  to 15,000
• Signal to Noise  40 db
• Speed  3.75 & 7.5 ips
• Motors 1
• Reels up to 7""
• Timing accuracy 0.3%
• Weight 33 lbs
• Price 289.50

• Freq Response  ?
• Signal to Noise  ?
• Speed 7.5 ips
• Motors 3
• Reels 10"
• Timing accuracy
• Weight 56lbs
• Price ?