neighborhood behind ralph's (monument canyon drive) market is Sprint dead zone, 1 bar at most, no 4g, 3g is extremely slow (350 down, 120 up). T-Mo cell phone has strong signal since 2008, haven't tested data speeds. Verizon appears to be okay as well based on mobile broadband bars on laptop stick. Again, this is the neighborhood surrounded by HILLS behind the Ralph's store and not necessarily the DB / Grand intersection itself.

I have been walking the same route for several years, and have never had a problem with reception until a couple of weeks ago. Now I can't get a decent signal at all. The only thing that has changed is a new cell tower that was recently built at Pantera Park. Who operates this tower? I know it is not Sprint, but am wondering if it is affecting my signal?

I have lived here for three years and some days are better than others. I live at the top of the hill so maybe that is why I could give it a score of 1 instead of 0. Basically if you even can receive or make a call, it doesn't stay connected long. Also, on Longview, there is absolutely no reception and if you turn left out towards Chino Hills you don't get any until you get up the hill past the cow field.

No Reception at all anywhere within the development. Could be caused by proximity to Hills nearby. The houses are built at the foot of the hills.

VERY GOOD RECEPTION - that's because of the combination of Sprint service and a Sanyo cell phone. Sprint has great service almost everywhere except San Dimas and Sanyo phones are VERY good quality when it comes to receiving reception and clear calls!

Last OCT 2004, I got ZERO reception at my home. For the last 3 months I have to call from outside of my home. But after AT&T join with Cingular,..PERFECT but you must change the Cingular sim card from 32k to 64k..then..volla! Full bar! Excellent! However, since AT&T and Cingular barely join together, the changing carrier from AT&T to Cingular has a dead zone spot. But after that, back to full bar. Anyway, I love my Cingular now. T-Mobile over this area suck too. Zero reception!

This seems to be a tough area for some carriers (I just saw someone report AT&T problems here). But Sprint is working solid at this intersection now.

Everyone seems to be switching companies. We have never had good reception even when we had TDMA phones. With so many users in this area I would think AT&T Wireless would do something.

I have never gotten good reception in Diamond Bar, especially in the center of town. With my Motorolla V60, I get a "no service" indication at Grand and D-Bar Blvd. Don't get ATT if you live here.

No reception at all. Avoid Cingular in Diamond Bar area. They are almost useless unless you live close to Freeway 60.