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 Post subject: Electronic Futures, Inc. Program Control
PostPosted: Nov Tue 14, 2006 2:05 pm 
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Joined: Jan Thu 01, 1970 1:00 am
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Location: Warner Robins, GA
I have an Electronic Futures, Inc. Program Control made probbably in the middle to late 60's. The internet has nothing on this company or this device (has no model#). I'll describe it the best I can since I don't have pictures. On the left front it has a listen jack(headphone) and underneath that it has a listen/talk jack (headphone/mic). Next to that you have a 4 position switch that determines which of the four channels you are listening to through the listen jack. under that you have 4 on/off switches that control which channels receive the mic signal from the listen/talk jack. next to that is the power switch. I will only descrobe one channel as the other 3 have the same controls and indicators. near the top of the front panel there are 2 neon indicator lights. One which is clear indicates the level of the program. the other which is red indicates when you have reached the max level the unit can handle without distortion. under that you have a level control and under that you have an on/off switch which controls whether that channels signal is present or not. On the back of the unit there are the signal connectors for each channel. I will describe one channel since they are all the same. You have a power connector for an Audio Notebook (whatever that is). Then you have an RCA jack labeled audio notebook/mic and a 1/4 jack labeled high input. On the left you have a fuse for the audio notebook power and a mains fuse. You also have a cable labeled loop which terminated into an old style 4 prong telephone plug. Each channel also has a small RF transmitter which is located on each channels PC board. The boards themselves which are removable are located on separate sub-chassis which are held to the main chassis by 2 screws (accessed from the bottom of the chassis which slides out of the cabinet). To remove each board you disconnect two 9 pin plugs (looks like standard 9 pin tube base) from each board and loosen the two screws from the bottom and slide the board back slightly and lift up. The same applies to the power supply board with the exception that you remove 3 plugs instead of 2. What this device does is it sends the RF modulated program info over a separate wire for each channel which I assume was a loop that went around the inside of the store where this was once used with one end tied to ground to provide signal to each receiver. Each board in the unit transmitted on one of four frequencies (which is determined by the crystal you had installed on the board) in the 119 KHz to 250 KHz range (at least that is the range that my particular unit transmitted in). All four boards are the same except for the crystal. It has a number on the bottom of the main chassis which may be a serial# or a service#, but I don't remember the number right off hand. I'll look at it tonight and get the number off it. Sorry for the long post, but I wanted to describe everything I know about the unit. Any info would be greatly appreciated.


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PostPosted: Nov Thu 16, 2006 8:46 pm 
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Joined: Jan Thu 01, 1970 1:00 am
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Location: Warner Robins, GA
I found out that this unit was used in classrooms for hearing impaired students. check this out. http://www.pa-shhh.org/ross/ross69.html


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