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The Whole Enchilada
Updated: 14-Aug-98
Status: Being reviewed

Please Note: The information in this document has just been translated over from the printed version (14-Aug-98) and is being reviewed. There are errors! This notice will go away once all the obvious errors are corrected. From there, this document will be upgraded over time.

ACOUSTIC COUPLERS

The older acoustic couplers become available from time to time from individuals selling off their Model T stuff. The same is true for the newer acoustic cups. Below is the Model 100 acoustic cups story, and a tip for using acoustic cups, successfully.

Almost from its beginnings in 1983, Tandy offered an acoustic coupler for use with its fast-selling, journalists-loved Model 100 laptop computer. Journalists, world wide, used these acoustic couplers with their "issued" Model 100 to transmit stores into all the famous newspapers--and those not so famous. The point is ... these acoustic couplers worked from just about every phone booth in the world. And, journalists, generally speaking, swore by them, not at them.

The original acoustic cups used round I.D. couplers. These were replaced in the mid '80s by square I.D. couplers to match the square ends of modern phones ... to improve the fit. In both cases, they incorporated an 8-pin DIN suited to the non-standard specs of the 8-pin DIN socket of the Model 100.

When using acoustic couplers, have a coat or towel available. Start by seating the mouth-end cup to the phone's hand piece. This will save you time. Then, make the call and wait for the high-pitched modem tone. Seat the ear-end cup to the phone's hand piece, then wrap the whole thing in a coat or towel. This will help keep unwanted noise out of the acoustic signal. Also, if possible, do not lay the computer on the same surface as the cups. It's amazing how the sound of typing fingers cuts through sound insolation.

ACOUSTIC COUPLER SPECS

Applicable Telephone Type ..... Type 500 (Rotary Dial)/Type 250 (Pushbutton)
                                with standard or European-style handset
Communications Mode ........... Full/Half-Duplex
Modulation Type ............... F.S.K.
Data Rate ..................... 300 baud
Operation Mode ................ Originate/Answer

Transmitting Frequency  Originate .. 1070 to 1270 Hz
                        Answer ..... 2025 to 2225 Hz
Receiving Frequency     Originate .. 2025 to 2225 Hz
                        Answer ..... 1070 to 1270 Hz
Transmitting Sound Pressure Level ..... Less then 1 N/M^2 (0.3 to 3.4 kHz)
Carrier Detection Level Half-Duplex ... -40 dBm
                        Full-Duplex ... -30 dBm

Environmental Noise Allowance . Less then 80 dB
Operating Voltage ............. +5V
Power Comsumption ............. Less then 30 mW
Operating Temperature Range ... 40oF to 104oF (5oC to 40oC)
Operating Humidity Range ...... 20% to 80% RH (non-condensing)
Dimensions .................... 3" (diameter) X 3-1/8" (height) 78 mm
                                (diameter X 79.5 mm (height)
Weight ........................ 13 oz (380 g) including cable

If you're looking for acoustic couplers, call Club 100. We can usually find a set or two within our resources.