I forgot to post this a few months ago, but I just thought I would share my experiences with getting my RD fixed.
After talking with some of the people on here I surmised that my detector wasn't picking up Ka band. I bought the rd on eBay (my mistake) and I guess it had some issues to begin with. One day it flashed a service code that resetting wouldnt fix. So I called Bel's service line and spoke to some lady who asked me for the Serial number, and then said something to the effect that to refurbish it was around 50 bucks (she gave me the exact price, I just don't remember what it was). She also said that I could either pay this now, or send the RD in and they would call me back once they receive it and look at it. Now call me crazy, but I think paying for a service before someone has even looked at the equipment is not the way to do it. I mean it might have gotten to them in 6 pieces or something, which would mean they would have to refund me minus the amount to ship it back. I opted to have them call me back. I also asked if they were able to replace the lenses and if that would cost anything extra. She said she would put it in the work order, but normally the techs do it anyway. She gave me an RMA number and an address. I thanked her and waited for a call back.
Two weeks later after not hearing anything I called them back. I got the same exact lady (who this time wasn't as friendly for some reason) and told her I was wondering what the current status of my RD was. I gave her my RMA number and she hastily replied (in a condescending tone) "We're awaiting payment", to which I condescendingly replied, "You never called me back." Some nervous typing on her end ensued, and she eventually said "Well, the total cost to fix it will be around 50 dollars." (once again I don't remember the exact amount). I gave her my credit card info, and it took another week and a half or so to get it back. It came with a nice little card of the techs name and what he did. I think it said "Replaced Radar Dome," or something like that. On the plus side the work came with a 90 day warranty on what was fixed, along with a new windshield mounting bracket, and a cigarette lighter cord. the display lens was replaced, but the front lens wasn't. It's not the biggest deal in the world though since it only had a few scratches.
So judging from my experiences, if you do send your bell in for service (although I think it's retarded) you may want to pay upfront.