Bicycle Mechanics - Computer problem

Is it normal for a bike computer speed readings to jump around?
I've got a Ascent Delta R, wireless. Sometimes there are no problems, other times the speeds change at random. I'll hold my speed steady and watch the reading jump from 17 to 25 to 6 and back. I tried moving the magnet closer, but nothing changed. The distances pretty much match up with what I know of my regular routes, so the average speed is close to correct.
Should I give up and get a new computer?

Try cleaning the contacts on the back of the unit and on the mount with a pencil eraser.

Aaron:)

Try cleaning the contacts on the back of the unit and on the mount with a pencil eraser.

Aaron:)

Two other suggestions:

1. The obvious one: Batteries?

2. Are you using something that interferes with the signal. HID lights are notorious for interfering with wireless computers.

Do the glitches happen at the same place? There have been a number of people noting that power lines and radio transmitters cause problems with wireless computers.

I had the same problem with my new wirerless Trek icite. I called them up and they said that was normal for a wireless. I just got another computer(Sigma wireless) and no problems yet. The person at Trek said the wired ones are more accurate. I don't know about that,good luck.

Well it's obvious the wired ones will be more accurate. There's no chance for the signal to drop from the sensor to the computer.

My wireless will occasionally show a weird max speed - - usually in the 70s . . . just seems to jump all of a sudden. Wish I was going that fast, but not quite . . . I've heard wireless computers can be subject to certain radio interference, etc. The total miles, avg. speed, etc. don't seem to be affected - - just the max.

Thanks

Both batteries were replaced in August when the problem first appeared. Worked for the 3 months before that. Worked better with new batteries but the problem didn't go away.
Not using a headlight during day rides and have no other electronics. Keeping a clear line between computer and sensor.
Happens in different locations, at random, and sporadically. Location, road conditions, weather, etc don't seem to make a difference.

I'll try cleaning the contacts again. Q-tip with alcohol.

May just keep it and put up with it. At least the clock works.
If I replace it, I may go wired.

Thanks

Both batteries were replaced in August when the problem first appeared. Worked for the 3 months before that. Worked better with new batteries but the problem didn't go away.
Not using a headlight during day rides and have no other electronics. Keeping a clear line between computer and sensor.
Happens in different locations, at random, and sporadically. Location, road conditions, weather, etc don't seem to make a difference.

I'll try cleaning the contacts again. Q-tip with alcohol.

May just keep it and put up with it. At least the clock works.
If I replace it, I may go wired.

Try a little emery cloth on the contacts. Some of my wired computers get a little strange when I change the battery and that usually sets them right.