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Entry  Thu May 19 03:13:54 2011, kiwamu, Update, Electronics, REFL11 not working 1305799561ZgerKtrd.gif
    Reply  Fri May 20 11:37:44 2011, Koji, Update, Electronics, REFL11 fixed (REFL11 not working) REFL11_transimpedance.pdf
       Reply  Thu Jun 2 23:10:10 2011, Koji, Update, Electronics, REFL11 test results (Re: REFL11 fixed) REFL11_test.pdf
Message ID: 4747     Entry time: Thu May 19 03:13:54 2011     Reply to this: 4756
Author: kiwamu 
Type: Update 
Category: Electronics 
Subject: REFL11 not working 

I took REFL11 out from the AS table for a health check because it wasn't working properly.

The symptoms were :

   - a big offset of ~ -3 V on the RF output. No RF signals.

   - The DC output seemed to be okay. It's been sensitive to light.

I did a quick check and confirmed that +/- 5V were correctly supplied to the op-amps.

It looks that the last stage (MAX4107) is saturated for some reasons. Need more inspections.

At the moment the REFL11 RFPD is on the bench of the Jenne laser.

 

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