From linley@netcom.com Fri Mar 3 21:43:17 1995 Received: from netcom7.netcom.com (netcom7.netcom.com [192.100.81.115]) by steroid.ecst.csuchico.edu (8.6.10/8.6.10) with ESMTP id VAA20859 for ; Fri, 3 Mar 1995 21:43:15 -0800 Received: by netcom7.netcom.com (8.6.10/Netcom) id VAA03891; Fri, 3 Mar 1995 21:42:54 -0800 Date: Fri, 3 Mar 1995 21:42:54 -0800 From: linley@netcom.com (Bruce James Robert Linley) Message-Id: <199503040542.VAA03891@netcom7.netcom.com> To: gchance@ecst.csuchico.edu Subject: UPDATE to 5200 switchbox info file Return-Receipt-To: linley@netcom.com Status: RO Pleace replace the 5200 switchbox info file with this one. It has only minor changes, but the current file on your URL is unreadable by some text based web browsers (esp. lynx). It seems that lines of text with a pipe (|) on the first line get eaten up by the browser so the diagram and the most critical part of the instructions are not seen. Sever people have emailed me to request a complete copy. Thanks. ----------------------CUT------------CUT-------------CUT------------------- Where do I hook up the power supply to my 4 port Atari 5200?! The early Atari 5200s came with an unusual switchbox which supplied power to the 5200 down the same wire the 5200 uses to send the video signal to your TV. The power supply plugged into the switchbox. Unfortunately, these switchboxes seem to have gotten lost over the years and are difficult to come by. Newer 5200s (the one with only two controller ports) had the power supply jack on the console itself. Fortunately, it is not difficult to construct your own RF/power supply box for the 5200. There is one difference, though. The original 5200 switchbox would automatically switch from your TV antenna/cable to the 5200 when you turned the console on. (This is probably the only reason why you would want power going into the switchbox.) With the RF/power box described below, you will need to use a standard game/tv switchbox to accomplish this function. What do I need to build the RF/Power box? The following parts are needed to construct the box. Where applicable, Radio Shack part numbers, and prices, have been provided. You may use another RCA jack in place of the F jack if you wish. I chose to use the F jack to avoid ever accidentally plugging the 5200 and TV cables in backwards, which would result in 11.5 volts DC going into your TV set, possibly damaging it. You can also wind your own choke (inductor) if you wish. RS# Part Price -------- ---------------------------- ----- 270-235 2"x2.75"x1.625" Aluminum Box $1.99 274-1563 Coaxial DC power jack $1.79 278-212 Cable TV type F jack (2 pack) $0.99 (optional, see above) 274-346 RCA type phono jack (4 pack) $2.49 272-131 0.01 uF Ceramic Disc capacitor (2 pack) $0.59 273-102 100 uH 2A Choke (inductor) $0.99 Total $8.84 + local tax And of course, you'll need a soldering iron or gun and some solder. How do I build it? Drill holes in the aluminum box for each jack to match the diagram below. The box itself forms the common ground connection to all three jacks. To reduce signal loss and ensure the common ground, I recommend using chrome or gold plated type jacks. F jack (to TV) __ +-------------I I-------------+ I I__I I<--- Aluminum box I I I I \ 0.01uF I Solder the leads of the capacitor to I \ _ Capacitor the center pins of the F jack and the I \/@I I RCA jack. Solder the leads of the I \/ I choke to the center pins of the DC I \ I power jack and the RCA jack. Screw the I Choke \ I box shut. You're done. See? That I ---I/////I---\ I wasn't hard at all was it? I _L _L I +------I I----------I I------+ I__I I__I DC power jack RCA jack (to pwr supply) (to 5200) How does it work? The capacitor transparently passes the video signal from the 5200 to the TV output jack, while at the same time preventing the DC power from the power supply jack from going into your TV. The choke (inductor) transparently passes the the 11.5 volt DC power to the 5200 via the RCA jack while at the same time preventing the video signal from escaping back down the power supply wire. The aluminum box itself helps keep the video signal confined to where it belongs to prevent possible interference and to ensure that as much of the signal as possible gets to your TV. For this reason, plastic boxes are discouraged. Power supply info (if you don't have one). The 5200 power supply is 11.5 volts DC @ 1.95 amps and has a standard type coaxial plug (center positive 5mm OD, 2.1mm ID). Feel free to drop me a line (at the address below) if you have any trouble or just to let me know how the project went. -- Reality (more or less)...........Bruce James Robert Linley |------------------| Internet...linley@netcom.com (linley1@aol.com if you must) | I run Solaris on | Postal.....3675 S. Rainbow Blvd. #107, Las Vegas, NV 89103 | my Atari 2600!!! | Amateur Radio.............KE6EQZ (-.- . -.... . --.- --..) |------------------|