Q I'm trying to build a home theater in my garage. Do you have any recommendations for HD projectors? I'd like to keep the price around $500. I found a Sharp XV-Z12000 for about $375, with about 200 hours of use on the lamp. Do you think it is a good buy?

A The Sharp XV-Z12000 was an OK projector in its day, and it seems like a fair deal for $375. But you have to look at the big picture (no pun intended).

The projector was introduced in 2005, making it a six-year-old design. It has a DVI input, not HDMI, so you need an adapter. That's easy to work around, but still not ideal and gives you an idea of how old of a projector it really is.

Also, how do you know for sure how many hours the lamp has been used? Is there a timer in the projector, and are you sure it is referring to that specific lamp? When the lamp does need to be replaced, the cost is stiff -- almost $500, more than the used projector. And DLP projectors like the Sharp can have color wheels that fail with time.

Finally, you can get a new projector for a few hundred dollars more than the cost of the used one.

Given all of these considerations, I wouldn't risk buying the used one.

Consider a new projector such as an Optima HD66 or an Epson Powerlite 705HD 720p. Both are available for about $600, and replacement lamps are about $200.

Don't forget that you will need a screen. There are some great do-it-yourself designs on the Web. I'll be writing more on the topic soon.

HDMI switch will work

Q I have a 6-year-old Panasonic HDTV receiver, the TU-PT700U, which has only one HDMI input. Is there a way to input several HDMI components into this single HDMI port on my receiver?

A You can use an HDMI switch box to use multiple HDMI connections with a single HDMI input. Make sure you get a powered switch box that supports HDCP. In the past, I've recommended models from Monoprice (www.monoprice.com) with good success. They sell for about $30.

Have receiver cleaned

Q I bought a vintage NAD 7175PE receiver for my turntable system about a year ago. There's now a recurring issue with the left channel intermittently cutting out. It is not cutting out entirely but going much quieter and then jumping back up to full level, along with some static. Could this be a bad relay?

A That sounds like dust in the dials and switches and is a common issue with older gear. A thorough cleaning will get rid of it. You can try contact cleaner yourself or, better yet, take it to your local audio repair shop for a thorough cleaning. Afterward, your receiver will be good to go for years.

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