I would like to know how to hook up a desktop PC to a regular TV so that I could have a larger and better picture to watch.

A:

This depends heavily on the video output port of your PC and the type of TV and its video input ports. If, by “regular TV,” you mean an older, analog model, you may be able to use an inexpensive cable that plugs into a standard computer video-out port, called VGA, and an older standard TV video input, which are called RCA, or composite plugs. You will also have to buy an audio cable. Another common type of video cable for older PCs and TVs is called S-Video. Newer digital TVs have standardized on a connector called HDMI, which combines high-definition video with audio so you need only one cable. Some newer PCs have HDMI ports, which easily connect to these new TVs using a common HDMI cable. Others have different types of digital outputs that require cables or adapters with a matching PC connector on one end and an HDMI plug on the other. If you’re going from an older PC with an analog port like VGA to a new HDMI-equipped TV, you’ll have to use an analog-to-digital converter box, unless your new TV has a VGA analog mode, as some do.

You can find Mossberg’s Mailbox and my other columns at the All Things Digital web site, http://walt.allthingsd.com. Email mossberg@wsj.com.

Apple’s second-generation iPad will likely have a front-facing camera and a rear-facing camera as well, both to be supplied by digital-imaging outfit OmniVision. That’s the word from Detwiler Fenton, which claims the former will be VGA and the latter a 5MP camera based on OmniVision’s CMOS sensor.

Seems a reasonable prediction–after all, the next iteration of the iPad is expected to support the company’s FaceTime video chat technology, and OmniVision is responsible for the camera in the iPhone 4.

That is changing. A new miniature-chip technology from Texas Instruments (TXN) called pico is making digital projectors truly portable, instead of merely luggable. For the past couple of weeks, I’ve been using two of the first pico-based projectors on the market, Dell‘s M109S and Optoma’s Pico PK-101.

The products are designed for different customers with different needs. Dell (DELL) positions the 13-ounce M109S as a notebook companion, best suited for work presentations. The four-ounce Optoma projector is designed more as an iPod or digital-camera accessory for watching movies and slide shows on the go.

The Dell M109S

Their portability requires compromises, most obviously in brightness and image resolution. The Dell and Optoma projectors, respectively, support 11 and 50 lumens — a standard measure of projector brightness. That’s far dimmer than top-notch projectors that offer several thousand lumens. So neither product excels in well-lighted rooms, where overhead and ambient lighting overpower their images. You can compensate somewhat for this weakness by placing the devices closer to the surfaces onto which they’re projecting — for example, a wall. But the darker the room you use, the better.

At about the size of a candy bar, the $399 Optoma device is the smaller of the two projectors and the one with the most intriguing possibilities for expanding the tiny screen sizes of mobile devices like the iPod.

It’s powered by a rechargeable battery that Optoma says lasts for an hour on full brightness or two hours on a power-saving setting (the projector comes with two batteries). The projector has a tiny speaker, but people who want decent sound will need to use headphones or external speakers.

In theory, the Optoma device is small enough to bring along on a camping trip to show a film on the side of a tent, or to a restaurant, where you could inflict a vacation slide show on dinner mates by projecting onto a napkin or tablecloth.

I tested it on a recent airplane flight by projecting an episode of “Mad Men” from an iPod touch onto the back of the seat in front of me. The seat was a dark blue with embossing on it, so it didn’t work very well. It’s best to project onto an unmarked, light-colored surface. The quality of the image was better when I lay in bed one night, projecting a video onto a white ceiling.

Even under the most favorable circumstances, however, I found the images from the Optoma projector very dark, muddling the outlines of characters and action on screen. Although Optoma says you can get up to a 60-inch image from the projector, 45 inches was about as big as I could make the image before it got too fuzzy.

Optoma says the projector will ship with an iPod-compatible connector cable when it goes on sale in the U.S. on Dec. 15, though the unit I tested didn’t come with one. I connected the device to my iPod touch using a $50 cable from Apple (AAPL).

Compared with the Optoma device, the $449 Dell M109S is a behemoth, yet it’s still only about the size of a short stack of drink coasters. Most projectors weigh at least a few pounds, if not more, which is big enough to make them a hassle to carry around. I barely noticed the Dell projector inside my laptop bag.

Unlike the Optoma projector, the Dell M109S has to be plugged into an electrical outlet to work. It comes with an unsightly set of connectors for plugging the projector into a video source, such as the VGA port found on most laptops and a composite video plug that is standard on DVD players. I was, however, able to plug my iPod touch into the Dell projector using the $50 Apple cable.

And unlike the Optoma, the Dell doesn’t have speakers. To get sound for a movie, you’ll need headphones or speakers, like those on a laptop.

Despite its extra bulk, the Dell M109S literally outshines the Optoma projector. It produces a bright image that I found very watchable, even if it wasn’t high-definition. I projected the movie “James and the Giant Peach” onto an interior wall of my house, creating an image that was about 7 feet, measured diagonally.

The Dell M109S includes a capability called keystone correction, a standard feature in most projectors that adjusts a projected image to give it the proper dimensions, rather than the trapezoidal shape that results when a projector is angled upward. The Optoma projector doesn’t have this feature. To get a normal rectangular movie image, I had to hold the projector level, toward the projection surface.

For business travelers who do presentations or for people who want to create a theater-like experience in a hotel room, vacation house or against a sheet in the backyard, the Dell projector would be a good fit. For now, the Optoma projector is a good idea that needs refinement.

• Email Nick.Wingfield@wsj.com. Walt Mossberg is on vacation.

This will continue to be obvious even after Apple (AAPL) announces “iPhone 2.0″ at this week’s conference for Macintosh and iPhone software developers. This new device, of course, is the updated version of the path-breaking model that was launched a year ago amid a blizzard of hype.

I continue to be an iSkeptic of sorts. I don’t own an iPhone, and even if all the rumored new features appear they probably won’t be enough to overcome Apple’s still-unfortunate choice of AT&T (T) as its telecom carrier partner.

True, no other device does exactly what the iPhone does. Conversely, the iPhone doesn’t come close to matching the most valuable features of the devices I do use, namely Research in Motion’s (RIMM) BlackBerry Curve and Nokia (NOK) N95. Let’s look at each to see why.

My primary device is the BlackBerry, for two major reasons. First, using T-Mobile’s clever UMA technology, which does a voice hand-off from cell to WiFi–something that works on several T-Mobile handsets, but not the BlackBerry Curve on other networks–I can use the phone (and save cell minutes and money) using voice over IP. This is especially helpful at home where the cell signal is weak, but also helpful given that it works with just about any WiFi network. AT&T hasn’t built UMA into its own network, and Apple’s first iPhone did not permit VoIP in any case.

Just as important, the BlackBerry’s physical keyboard–small keys that are nonetheless accurate and have a nice tactile response–makes it a mostly excellent email tool.

Mostly, but not completely–because BlackBerry’s email capabilities are designed around Microsoft Exchange. I do use Exchange for one email account, but IMAP on several others. And the BlackBerry has no IMAP client software that even understands how to flag a message as having been replied to, much less an understanding of folders.

I would pay good money for a solid IMAP client for the BlackBerry, but no one seems to care enough to create one. I suspect there’s a serious market for the first company that does this.

If the iPhone had a tolerable keyboard–and I find the virtual, screen-bound keypad nearly useless–it would be a vastly better email device than the BlackBerry, especially because it absolutely gets IMAP and is about to work with Exchange servers.

The iPhone’s camera is roughly equivalent to the one on the Curve: inadequate at best, with relatively low resolution and no video mode. Nokia’s N95, by contrast , is a great camera, with a 5 megapixel still resolution and 30-frame-per-second VGA video recording and playback.

I can “tether” the N95 to my laptop and use it as a modem; no such common-sense usage with the iPhone. The N95 also has WiFi (and handles VoIP) and 3G, invaluable for international travel; strong rumors say the iPhone will remedy the 3G situation in the new version.In fact, the N95 has almost too many high-end features, a key reason it has especially poor battery life. GPS is another N95 advantage; again, there are strong indications that the iPhone will also have it–and the large screen on the Apple device makes maps a joy to use and view.

I do love the iPhone as a media playback device, however. That’s why I bought an iPod Touch, which is roughly the same size and has become my portable media system of choice, especially on airplanes. And when it comes to Web browsing, it’s absolutely no contest: The iPhone blows away the Blackberry and N95.

Apple raised the bar in a serious way when it comes to software. While Nokia’s operating system has been much more open than the iPhone’s (or BlackBerry’s)–something Apple has halfway remedied with its semi-open new development model–Nokia has a long way to go to get even close to Apple in basic usability. The BlackBerry is quite easy to use, but still far behind Apple in many respects.

Will I buy an iPhone when the new models hit the stores? I still don’t know. Apple’s insistence that legitimate software will only be available through its online store is part of the company’s typical arrogance. And its continued lock-in with AT&T is close to a deal-killer no matter how good the device may be.

Of course, you can “jailbreak” even the current iPhones. And it’s looking as though the new ones will be even more malleable, at least theoretically.

No matter what Apple introduces, the compromises will continue, however. But the time is almost in sight when we’ll have just about everything we want–not just what we absolutely need–in our handhelds. Not real soon now, but sooner than we might expect.