The Sega Genesis connects to a TV in much the same way as other consoles of similar vintage. But there are some dangers unique to the Genesis that give you an opportunity to damage either the console or your TV. We certainly don’t want that. Here’s how to hook up a Sega Genesis to a TV without damaging either.
Some Genesis parts are interchangeable with other systems, but not universally. That means it’s very important to verify the AC adapter you plan to use, as well as the AV cable you want to use, to avoid damage to your console, your TV, or both.
How to hook up the Sega Genesis power supply and controllers
Let’s get the more straightforward part out of the way first. If you already know this stuff and just need to connect the TV, feel free to scroll down about five paragraphs. But I do encourage you to read the caveat about the AC adapter.
The power supply brick plugs into the round connector on the back of the unit. The connector on a first-generation Genesis is the same as a Nintendo NES, but while a Sega adapter works with an NES, a first-party Nintendo adapter will damage a Genesis. I have more tips on Genesis AC adapters if you need them.
You can get a semi-universal adapter that works with the SNES, original NES, and first-generation Sega Genesis if you lost yours. The cost on these adapters has really come down in recent years due to the resurgence in popularity of retro consoles, so it’s easy to get one for under $10 now. But always verify any AC adapter you use is outputting center-negative DC voltage, not AC. One of these adapters makes it really handy if you have multiple vintage consoles you want to swap in and out.
The second-generation Genesis uses a different power adapter. Nintendo adapters don’t fit that connector, so that’s a good thing.
Cartridges plug into the slot in the top of the unit. Never plug or unplug a cartridge with the unit powered on. Power off the unit first.
Controllers plug into the front of the unit. If you’ve lost your controllers, replacements are also available. Much like other consoles, the first-party units tend to be better. If you have a choice, look for the later Sega controllers that have six buttons.
How to hook up a Sega Genesis to HDMI
Some newer TVs don’t have composite inputs. That makes connecting a Sega Genesis to those types of TV more difficult, and the HDMI mods for some consoles cost more than the console is worth. But there is one HDMI solution for the Genesis that isn’t mega expensive.
My favorite all-around HDMI option for the Genesis is the Hyperkin HDMI adapter, which costs around $30. The quality isn’t as high as the HDMI options for some other consoles, but unlike those, this one doesn’t require internal modifications. The conversion does introduce a bit of lag and the color isn’t always 100% accurate, but overall it’s a good solution that doesn’t cost a fortune.
To connect the Hyperkin HDMI adapter, plug the round DIN connector into the AV port on the back of the Genesis. The Hyperkin comes with an adapter to convert the Gen 2/3 connector for the Gen 1 Genesis, so plug in the adapter if you need it. Then plug the HDMI connector into the back of your TV. You’ll also need to connect a phone charger to the Hyperkin adapter for power. Plug the charger into the wall, and the USB connector into the Hyperkin.
One other option at this point is to simply use a modern Genesis mini console with HDMI. The mini version has an HDMI connector in the back that plugs straight into an HDMI connector on a TV with a standard HDMI cable. If you already have a vintage Genesis console, a $30 HDMI adapter is cheaper. But a mini is more affordable than a vintage Genesis plus an adapter plus some games. This will probably be either your favorite or least favorite option, but it’s an option.
Connecting a Sega Genesis to S-Video or component video
You may run across some websites or Ebay listings claiming easy ways to connect your Genesis to S-Video. There are no S-Video signals on the Genesis AV port. It is possible to fake S-Video from composite well enough to get a picture. Radio Shack used to sell an adapter to do just that in a pinch. And these modern cables do something similar. But the video quality isn’t the same as S-Video. So while the Genesis/S-Video cables may work, they won’t give any improvement over just using composite, and the picture can actually degrade. It’s really better to save your S-Video input for a system that can use it.
Component video poses a different challenge. The RGB signals on the Genesis are really intended for late 80s computer monitors like a Commodore 1084.
In the interest of honesty, go with composite or HDMI.
How to connect a Sega Genesis to a TV via composite video
Composite was the optimal option for a lot of us in the 1990s, and millions of TVs have composite outputs, so this is an option likely to be available to many people. To connect a Sega Genesis to a TV via this type of connection, all you need is a Genesis composite video cable. Be sure to get the right type for your model of Genesis. The earlier Gen 1 Genesis has an 8-pin full-size DIN connector. Later Gen 2 and Gen 3 Genesis models use a smaller connector with 9 pins.
Simply plug this cable into the round AV output in the back of the Genesis, then plug the yellow video lead into the yellow RCA jack in the back of your TV, and the red and white audio leads into the red and white jacks in the back of the TV. If your TV doesn’t have two audio inputs, or your cable doesn’t have two leads, just use whichever one you have and leave the second one disconnected.
On some televisions, the set of component inputs does double duty as composite as well. On a TV like that, one of the jacks will probably be green and yellow. Try using that jack.
After connecting to composite inputs, select the composite input with your TV remote and turn on your Genesis to play.
A word of caution about cheap AV cables
There are a lot of DIN cables floating around with four RCA jacks on the end. These cables can be very useful, but in the case of the Genesis, they’re dangerous. There is a pin on the Genesis AV connector that outputs 5 volts. Plugging this into an audio or video jack on your TV has the potential to damage the set, as the set is really expecting 1-2 volts on those plugs. If you’re going to use a random AV cable, double check the voltages with a multimeter before using them. Here are some tips on that.
Also be careful about Commodore and Atari video cables. They use a similar looking connector, but the pinouts aren’t the same. It’s really best to just buy a Genesis AV cable, then label it. Also label your AV cables for other systems so someone doesn’t inadvertently use them on the wrong system someday and damage something.
How to hook up a Sega Genesis to RF
Last and least, you can hook up a Sega Genesis to RF if you don’t have any other options. A good number of TVs can still accept the broadcast analog signal that the Sega Genesis RF connection used. The options vary depending on whether you have the original model or the later 1997 cost-reduced model. The Sega Genesis came with an RF cable, but if you lost yours, the Genesis can use an original NES RF video cable, exactly the same way as the original NES.
You can also use a cheap F connector plug, which monopolizes the antenna input but gives a higher quality display. If you want to be sure you’re getting the right thing, look for an Atari F plug adapter. If you’re willing to hunt, you may be able to get a better price if you search for an RCA female to male F connector. Just make sure whatever you buy looks like the picture to the right. It’s OK if the color doesn’t match, but the connectors need to look the same. The price can vary a bit of course, but you should be able to find one for around $6. In addition, you’ll need an RCA video cable if you don’t have one.
The caveat with using RF, besides the lower quality, is also lower reliability. The capacitors in Sega’s RF modulators are starting to fail. So a Genesis may work fine over AV but not reliably over RF.
Making the connection to RF
If you’re using an RF cable, connect RCA plug on the cable to the RCA jack on the back of the Genesis, then connect the round end to the antenna connector on your TV. Connect your antenna or other video lead into the round antenna connector on the Genesis’ RF cable.
If you use an F connector, connect the adapter to the antenna input on the TV, then connect an RCA cable between the adapter and the RF output on the back of your Genesis console.
Next, insert a cartridge and turn on your Genesis, then perform a channel search on your TV using its remote. Your TV hasn’t seen an analog signal on channel 3 or channel 4 since 2009, if it ever did, so you have to instruct it to look. After the channel search finishes, you’ll see your Genesis output on either channel 3 or channel 4. There is a switch on the back of the Genesis to change between channels. You may get a better picture on one or the other.
Connecting two RF switch boxes together
As tempting as it may be to connect two or three RF switch boxes together and run Atari on channel 2, Nintendo on channel 3 and Sega on channel 4, that doesn’t work. The multiple switch boxes conflict with each other.
If you can’t get your Genesis to work over RF, you probably missed the channel search step, or didn’t have your console powered on when you performed the search.
The convenience factor
With analog television having come to an end in 2019, this isn’t an option that we can count on forever. But on a TV that doesn’t have any other connections besides HDMI, this option is the one most likely to work. Assuming your Genesis’ RF modulator hasn’t given up the ghost. But if this method works, it’s certainly convenient. You can use the same RF adapter with an NES and SNES, and get an AC adapter that works with all three, so you can swap consoles by changing only two cables.
But there are other options for connecting those consoles too. So if you have those consoles, I recommend you read my blog posts on connecting an Atari, NES, SNES, and N64. They have a lot of similiarities, but each console has a quirk or two. You may be able to take advantage of those quirks to connect multiple consoles to the same TV and reduce or even eliminate swapping.