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Mohawk 400 → ← 44 (BR-1)
Portable tape cartridge audio recorder
- this page is a stub
Midgetape 300 was a portable transistorised
audio tape cartridge recorder,
introduced in 1957 by Mohawk Business Machines in New York (USA)
as a solid state 1 successor of the valve-based Midgetape 44.
Although initially intended as a dictation machine, it was also used in
surveillance as it could easily be hidden on the body. This was further promoted
by the availability of a wristwatch microphone and a shoulder holster.
It is known that these devices were used by the CIA.
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In late 1957, the Midgetape 300 was succeeded by the nearly identical
Midgetape 400 'Chief',
which added Automatic Volume Control (AVC) when recording.
At the same time, accessories were released to make the device
even more suitable for surveillance and covert recording [G].
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In this context, solid-state means that it is built with transistors
instead of valves (tubes).
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Device Miniature audio recorder Purpose Dictation, covert recording Model Midgetape 300 Manufacturer Mohawk Business Machines Year 1957 Predecessor Midgetape 44 (BR-1) Successor Midgetape 400 Medium Tape, Dupont Mylar base Width 6.35 mm (1/4 in) Speed 4.76 cm/s (1 7/8 in/s) Cartridge 45 min/side Input ≥ 1 mV, 2000Ω Output 10 mW into 2000Ω Response 150 - 5000 Hz W&F < 0.7% S/N 42dB Bias 20 kHz Transistors 4 Dimensions 220 x 100 x 55 mm Weight 1.2 kg Price US$ 250 (1957)
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- 1 x GT81
- 1 x GT-82
- 2 x 2N406
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401 Leather carrying case 402 Internal Power Amplifier with built-in speaker 403 Mains power supply unit (for 110V AC only) 404 Transcribing Control [5] 405 Cowhide briefcase concealment (with hidden microphone) 406 Same as 405, but without hidden microphone 407 Telephone pick-up coil 408 Wristwatch microphone 409 Concealable lapel microphone 410 Throat microphone 411 Standard microphone/speaker with clip stand 412 Shoulder holster 420 Car battery converter (12V) 421 Stethoscope-style earphones 422 Combined speaker/microphone with PTT RL-60 Tape cartridge 2 x 30 min. RL-90 Tape cartridge 2 x 45 min. T-12 Motor battery (12-15 hours) T-50 Motor battery (50+ hours)
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© Crypto Museum. Created: Thursday 09 June 2022. Last changed: Monday, 12 February 2024 - 15:06 CET.
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