Odyssey:Video Output Notes

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The Magnavox Odyssey outputted video via an RF connection, using a proprietary Game Cable. There are currently options that allow you to output a better quality, or more reliable signal, however they may not be easy to obtain.

Original Video Cable & Odyssey RF Switch Box

Originally, the Odyssey Game Cable would connect to the console via a proprietary connector, which is not commonly used anymore. The original cable is approximately 15 feet in length. The other end of the cable (using the same type of connector) would then be connected to an old-style mechanical TV RF-switch box. This switch box had a slide lever that allowed the user to switch between using the Odyssey console and receiving signals from a remote television station. The RF switch box then connected to the television's antenna screws via a pair of fork connectors (Link).

This output method is arguably the worst available option, as it will be more prone to interference than an RF connection which is output directly from the console using RCA style connectors converted to coax. Additionally, these RF switch boxes (which were also used on second generation consoles such as the Atari 2600 and the Intellivision), are approximately 50 years old, with their metallic components being prone to rust and related damage.

Closeup of Odyssey proprietary connector.png

Odyssey Original RF Connection.jpg Odyssey vs Intellivision switch box comparison (front).jpg Odyssey vs Intellivision switch box comparison (rear).jpg

New RF Cable with replacement connector

Cable solution:

The original Odyssey cables and RF switch boxes may be difficult to find in standalone online sales, and may have to be purchased as part of a complete Odyssey console set. If this is prohibitive, the stock game cables can be replaced with good-quality replacements - as is the case with many older consoles which are RF-only. Well-shielded coaxial cable, such as the RG-59, or the later RG-6 models can work for this purpose. To ensure quality, upon stripping back the cable, the user should see that the cable has metal foil on the outside, as well as a wire mesh and a thick solid conduit in the middle, surrounded by foam.

A very high quality version of the above coaxial cable, such as the Belden 1505A RF Cable (from Blue Jeans Cable) may result in less RF interference on-screen. However these cables may be more expensive than arguably superior solutions, such as a good-quality composite mod.

Connector solution:

Once the user has obtained an appropriate length of RG-6 or other coaxial cable (the original Odyssey Game Cable is approximately 15 feet in length) and some heads, they will need to snip the end off the new cable, pull the foil back, attach a new connector and crimp them using a crimping tool. The difficulty level of this task should be somewhat lower than making DIY SCART cables, or CAT6 networking cable.

If the user has an original Odyssey Game Cable where the actual cable has been irreparably damaged but the proprietary connectors are in good condition, these connectors could be crimped to the brand new coaxial cable.

Measurement1.jpg Measurement2.jpg The diameter of these connectors varies slightly between 4.17mm and 4.39mm (see left).

Large measurement.jpg When the measurement includes the plastic casing around the connector, the diameter is approximately 10.95mm


Alternatively, the user will need to choose a modern replacement connector that will fit into the Odyssey's Game Cord port. The proprietary tip is somewhat similar to modern DC adapters, so a correctly-sized modern power adapter could in theory be adopted for this purpose, but the internal and external diameter of the new connector (i.e. the thickness of the metal part) should be measured with a calipers tool to ensure compatibility with the Odyssey's port. Then the user just needs to find the right DC female power plug to crimp to the coaxial cable.

Another possible candidate for this mod would be a Coaxial TV Aerial Connector Plug, as this is very similar to the original Odyssey connector, but without the outer metal section around the pin.

Replacement connector size from RazorX.png

It may be difficult to find a DC adapter (see above) that will fit securely into the Odyssey's Game Cord port; such a connector would have to be female, but I have sampled all eight DC adapters that came packaged with a Mercury Eco Universal Power Unit 1500MA 661403, and none of them fit securely.

The other end of the cable will output to a regular TV coaxial connection using any standard RF TV Coaxial F Plug Female Adapter, such as this unit designed for the Magnavox Odyssey or this similar unit marketed for the Atari 2600.

This could then output directly to an RF-capable television or to an RF Coax-to-composite demodulation solution such as a VCR (or a dedicated device).

New RF Cable soldered directly to the main board

That Tim Guy's Replacement Video Cable mod works similarly to the above solution except - instead of finding a replacement Odyssey-compatible connector to attach to the new coaxial cable, the cable is soldered to the back of the console's main board, and is fed through the Game Cord port on the rear of the console.

This should be a relatively simple modification, as the cable is soldered to the board at only two points. In the original video, the black wire is ground (the ground lane goes to all the major grounding points on the board), and the red cable is the video signal. A thin gauge (somewhere between 18-24) would be fine. An RF cable with a specific impedance of 75 Ohm would be suitable for this application. The user should also double-check its thickness to make sure it can fit through the Game Cord port.

While this may be a practical solution - it should be noted that if the voltage levels are not correct, soldering directly to the board in this way may potentially create an unsafe circuit that could damage the console. The user should go over a transistor and a capacitor, prior connecting the raw video signal to a TV, per Boojakascha's instructions in the attached video.

Composite Mod: Boojakascha's video board

TBC

Magnavox Odyssey 1 AV Mod (Sergei277)

TBC