Magnavox Odyssey 300
 | |
| An Odyssey 300, with one knob for each player | |
| Specifications | |
|---|---|
| Manufacturer | The Magnavox Company |
| Type | Dedicated home video game console |
| Released | 1976[1][2] |
| Intro price | US$69[1] |
| CPU | None; one game chip, Magnavox IC1 612114 (General Instrument AY-3-8500)[3][2][1] |
| Memory | None |
| Storage | — |
| Display | Black and white, RF output on VHF channel 3 or 4[4][5] |
| Sound | Built-in speaker; no on/off switch[5][3] |
| Power | Six C cells or a 9 V AC adaptor[5] |
| OS / Firmware | — |
| Successor | Magnavox Odyssey 2000 |
| Model no. | BG7500[5] |
The Magnavox Odyssey 300 (model BG7500) is a dedicated home video game console made by Magnavox from 1976. It plays Hockey, Tennis and Smash in black and white, with on-screen scores, an automatic serve and three skill levels, and each player has a single knob that moves the player up and down.[5][6][1] Where the Odyssey 100, 200, 400 and 500 use several Texas Instruments chips, the 300 is built around one General Instrument game chip, the AY-3-8500, which Magnavox lists as IC1, part 612114-1.[2][1][3]
History
[edit | edit source]Pong-Story describes the Odyssey 300 as Magnavox's answer to the Coleco Telstar, the first console built on the General Instrument AY-3-8500. Magnavox brought it out in 1976 while the improved Odyssey 200 with digital scores, which became the Magnavox Odyssey 400, was still in development.[2] Wikipedia gives an announcement in May 1976 and a release in October at US$69.[1] Magnavox's service manual for the BG7500 is dated October 1976.[5] Magnavox also built the equivalent of an Odyssey 300 into a colour television, the model 4305.[2]
Hardware
[edit | edit source]Circuit
[edit | edit source]The board carries IC1 and four transistors. Q1 is the voltage regulator for IC1, Q2 the 2 MHz oscillator that clocks it, Q3 the sound amplifier and Q4 the RF oscillator inside the shielded RF section.[7][3] Pong-Story notes that the AY-3-8500 needs little else: the controls, a clock circuit and the parts that combine its video outputs and modulate them onto a television channel.[2] On the BG7500 the wall, player and ball video leave IC1 on pins 24, 10, 9 and 6 and are combined through diodes D2 to D5.[7]
| Ref | Function (schematic) | Magnavox part |
|---|---|---|
| IC1 | Game chip | 612114-1 |
| Q1 | Voltage regulator | 610224-1 |
| Q2 | 2 MHz oscillator | 610139-2 |
| Q3 | Sound amplifier | 610232-2 |
| Q4 | RF oscillator | 610139-2 |
| Z1 | Zener diode for the regulator | 530073-1039 |
Power
[edit | edit source]The console runs from six C cells in a battery holder or a 9 V AC adaptor that plugs into a socket at the top back of the case. Magnavox's booklet advises taking the cells out if the console is normally run from the adaptor, to prevent damage from leaking cells.[5][6] Q1 drops the 9 V supply to about 6.4 V for IC1 pin 4, with its base held by the zener Z1. Magnavox's schematic notes that early consoles used a 6.8 V zener with a diode, D9, in series, and later ones a single 7 V zener.[7]
Controls
[edit | edit source]The centre panel has the GAME switch (Smash, Tennis, Hockey), the SKILL switch (Novice, Intermediate, Expert) and the three-position POWER/RESET switch: off, on, and a spring-loaded reset that clears the score.[6][3] Each player's knob is a 500 kΩ control, R10 for the left ("visiting team") player and R8 for the right ("home team") player.[3][8] The channel switch is inside the case on the board.[6] There is no sound switch; Magnavox states that no provision was made to turn the sound off.[5]
The SKILL switch sets the ball speed, player size and ball deflection together:[6]
| Skill | Switch position | Ball speed | Player size | Deflection angles |
|---|---|---|---|---|
| Novice | Bottom | Slow | Large | Two |
| Intermediate | Middle | Slow | Small | Four |
| Expert | Top | Fast | Large | Four |
Scoring and serve
[edit | edit source]The score is shown on screen. The ball is served automatically from the side that won the previous point, and after either side reaches 15 points the ball keeps being served but neither player can return it, until the game is reset.[5][6] A different tone sounds for a hit on a player, a hit on a wall and a point.[5]
Troubleshooting
[edit | edit source]Magnavox's service manual has no symptom chart. It gives a voltage chart for IC1, transistor voltages on the schematic, and two adjustments: the 2 MHz oscillator and the channel 3 and 4 RF oscillator. Symptoms and checks are on Magnavox Odyssey 300 Troubleshooting Guide, the adjustments on Magnavox Odyssey 300 General Maintenance and the three electrolytic capacitors on Magnavox Odyssey 300 Capacitor Replacement Guide.[5][7]
Documentation
[edit | edit source]Magnavox Service Manual No. 6504 for the BG7500 and the Odyssey 300 instruction booklet IB 2984-1 are hosted on the wiki and described on Magnavox Odyssey 300 Documentation.[5][6]
Gallery
[edit | edit source]-
The GAME, SKILL and POWER/RESET switches -
The AC adaptor socket at the back of the centre panel -
Main board, component side (Service Manual No. 6504, pp. 6504-5 and 6504-6)
.jpg)
Related pages
[edit | edit source]- Magnavox Odyssey 300 General Maintenance
- Magnavox Odyssey 300 Troubleshooting Guide
- Magnavox Odyssey 300 Capacitor Replacement Guide
- Magnavox Odyssey 300 Documentation
- Magnavox Odyssey 2000, the four-game model that followed it
- Magnavox Odyssey 400
References
[edit | edit source]- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Wikipedia, "Magnavox Odyssey series" (retrieved 2026-10-19), section on the Odyssey 300: announced in May 1976 and released in October for US$69, the AY-3-8500 chip, single control knob, three difficulty levels and digital on-screen scoring.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 David Winter, Pong-Story, "Other Magnavox Odyssey systems" (retrieved 2026-10-19): the Odyssey 300 of 1976 as Magnavox's answer to the Coleco Telstar, its General Instrument AY-3-8500 chip, the 2 MHz clock and the few other parts the chip needs, and the Magnavox 4305 television with an Odyssey 300 built in.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Magnavox, Service Manual No. 6504, October 1976, p. 6504-2: BG7500 replacement parts list (coils, capacitors with type, value, rating and part number, controls and switches, semiconductors, miscellaneous), antenna/game switch parts list and cabinet parts list. Hosted as File:Magnavox Odyssey 300 Service Manual 6504.pdf.
- ↑ Nerdly Pleasures, "Sears (Atari) Tele-games Pong vs Magavox Odyssey 100 - Battle of the First Pong Consoles", 7 August 2022 (retrieved 2026-10-19): the later Odyssey models, with the 300, 2000 and 3000 in black and white; and the faults the author fixed on an Odyssey 100 (a noisy channel switch, dirty power and ball reset switch contacts, a broken battery holder contact). Owner's hands-on report.
- ↑ 5.00 5.01 5.02 5.03 5.04 5.05 5.06 5.07 5.08 5.09 5.10 5.11 The Magnavox Company, Service Manual No. 6504: BG7500 Odyssey, first issue, October 1976, p. 6504-1: general information (6 C cells or an optional AC to DC 9 V adaptor; Hockey, Tennis and Smash; Novice, Intermediate and Expert skill levels; on-screen scoring, automatic serve, 15-point game; a different tone for each hit or point and no provision to turn the sound off), the service adjustments (2 MHz oscillator; channel 3 and 4 RF oscillator) and typical operation. Hosted as File:Magnavox Odyssey 300 Service Manual 6504.pdf.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 The Magnavox Company, Odyssey 300 Installation and Game Rules, IB 2984-1, 1976: introduction and automatic features (p. 2), the antenna-game switch and game cord (pp. 3 and 4), battery installation and the channel switch (p. 5), the control panel (p. 6), the power/reset, game and skill switches and the player control (p. 7), Smash, Tennis and Hockey (pp. 8 to 10). Hosted as File:Magnavox Odyssey 300 Installation and Game Rules IB2984-1.pdf.
- ↑ 7.0 7.1 7.2 7.3 7.4 Magnavox, Service Manual No. 6504, October 1976, pp. 6504-3 and 6504-4: BG7500 schematic diagram, with the transistor voltages marked on it, the note on the early and late production regulator zener, and the IC1 voltage chart with its notes 1 to 8. Hosted as File:Magnavox Odyssey 300 Service Manual 6504.pdf.
- ↑ Magnavox, Service Manual No. 6504, October 1976, pp. 6504-5 and 6504-6: main P.C. board viewed from the component side (board 211077-1) and a drawing of the console's controls. Hosted as File:Magnavox Odyssey 300 Service Manual 6504.pdf.