Channel B noisy on a 3205

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Channel B noisy on a 3205

Post by weihong1988 » Wed Dec 05, 2007 4:28 am

I have a 3205, and this morning when using it i observed that channel B produces a very weird noise signal of +/- 20 mv. Any measurements taken using channel B was invalid due to the noise signal, such as a square wave from a function generator. Strangely, the scope calibration signal from the 3205's internal signal generator was displayed OK.

I tried shorting the probe tip with the clip, yet i still see +/- 20mv of noise (no change). Unplugging the probe from channel B, and the noise goes away. It may be the probe, but i swapped channel A's probe with B and the noise was still there. Only channel B has this problem. Any help on this will be appreciated.

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Post by picojohn » Wed Dec 05, 2007 3:45 pm

Hello weihong1988,

If the problem is present on one channel only, then it is quite possibly hardware related.

If you recently purchased the unit, then you should contact the supplier or, should you wish to return the unit to us, then please send an email to with the following details:

Contact name
Unit & Serial No.
Brief problem summary

We will then issue a returns number and address.


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