Slow Networks Experiment 4: Videotelephony

still of "The End" from movie "Mary Poppins" shown on Mitsubishi videophone

Continuing on from “Slow Networks Experiment 1: Over-Air Tranmission” and “Slow Networks Experiments 2 & 3: VHF Radio Transmission,” this time we experimented with videotelephony or videophones – the ancestor of today’s Skype and Zoom. Details below.

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Date:
Dec. 18, 2020

Location:
Media Archaeology Lab, 1320 Grandview Ave., Boulder, CO 80309

Participants:
Lori Emerson, libi striegl

Network Type: 
One-to-one
Wired telecommunications via 300? Baud model 
Videophone
Self-contained mini network

Materials:
Mitsubishi Visitel (1988)
12V/2.5 amp/RJ-11 combination power and transmission cord
Panasonic Videophone (Visual Telecommunication System) Panasonic WG-R2 2 Way Telephone Visual Communicator (1989?)
Panasonic 13.5 AC/DC power supply
RJ-11 cable
6P2C connector 

Procedure:
We ran the built-in 12V/2.5 amp/RJ-11 combination power and transmission cord from the Mitsubishi Visitel to the wall outlet and to the input jack on the Panasonic Videophone. We then ran a 13.5 V/2.5 amp power supply from the Panasonic to the wall outlet. We connected a second RJ-11 cord from the output jack on the Panasonic to the input jack on the Mitsubishi. We then sent images of ourselves back and forth between the Panasonic and the Mitsubishi videophones. Both automatically saves images so we scrolled through and pressed the reset button to clear the memory. We noted that the Mitsubishi has a smaller memory that allowed us to save about 5 images. The Panasonic allowed us to save about 12 images. We also noted that both senders/receivers would need an analog phone line in addition to the videophones as they’d need to use a phone to dial a number and send/receive.

We also hooked the Panasonic up to the VCR using a standard AV cable with RCA connectors plugged in to “video in” on the Panasonic and “video out” on VCR. The Panasonic was also connected to the Mitsubishi via the combination power and RJ-11 cord. We used the Panasonic as a display screen and transmitted stills of the movie Mary Poppins to the Mitsubishi

We also hooked the Panasonic up to an NES game console using a standard AV cable with RCA connectors plugged in to “video in” on Panasonic and “video out” on the NES. The Panasonic was also connected to the Mitsubishi via the combination power and RJ-11 cord. We played “Super Mario Bros. 3” using the Panasonic as a display and transmitted images of the game to the Mitsubishi.

Results:
We learned that the Panasonic is basically a very low resolution TV with a built-in modem and a camera. Also, videophones do not send video but rather they send stills. We were able to capture video in stills but, again, we were not able to send video out.