Power Supply Pinouts
The external power supply of the 99/4A supplies only AC power to the console, in other words it is just a transformer. DC conversion and regulation takes place inside the console. The voltages /currents are:
- Pins 1-2: 16V AC 2A
- Pins 2-4: 8V AC 0.16A
- Pin 3 is not connected.
Video Output Signals
This is a little more complicated. There are two versions of the TI. The NTSC (US) version has a five pin DIN socket, that outputs composite video signal and audio. It is very easy to construct a cable to connect this to the front video /audio inputs of a modern TV set and get superior picture quality. Keep in mind however this composite video is NTSC so you need a TV set which is NTSC compatible. Latest european models are able to decode NTSC video signals fed to front inputs. Of course, if you leave in the US you have no problem!
The European version of the TI has a six pin DIN socket. It does not output composite signal, but a much more complicated type called R-Y, B-Y, Y. This cannot be easily converted to composite video. Actually, a circuit is needed to convert it to RGB signal. It can then be fed to the SCART input of a TV set. I am in the process of designing such a circuit, and will publish details on this site when available. The socket also supplies 12V DC and audio.
- Audio (Modulator cable: Yellow)
- B-Y Video (Modulator cable: Green)
- R-Y Video (Modulator cable: White)
- Y Video
- (Modulator cable: Blue)
- +12V (Modulator cable: Red)
- Ground (Modulator cable: Violet)
The modulator cable colors maybe different in different versions of the modulator. These are taken from my original PAL modulator (constructed in Italy for TI, by SIEL Electronics)
Pinout of the US Console (Socket View, Plug Side)
- Composite Video (NTSC)
Cassette Tape Interface Pinout
The tape interface is very straight forward, and it should be no problem to construct an interface cable yourself. You will need a 9 pin DB female connector and two 3.5 inch mono jacks. (And a 1/8 inch jack for the motor remote if you need it). You may substitute the mono jacks for stereo ones if you plan to connect the cable to a stereo deck (or even a minidisc!) In this case, make sure you feed the signal to both the left and right channels (short circuit the left and right pins on the jack)
Female Connector (on cable)
(Female connector view, front)
- Remote Ground
- Microphone Ground
- Earphone Ground
Pins 4,6,7 are used for the second cassette recorder (CS2). Why would you ever want to connect a second recorder to the TI eludes me. Isn't the first a pain already?
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