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Message ID: 3604     Entry time: Fri Sep 24 00:56:35 2010
Author: koji, tara 
Type: Update 
Category: Electronics 
Subject: testing TTFSS 

We found that a transistor was broken from yesterday spark too. We partially fixed TTFSS, and it should be enough for  testing purpose.

 

From yesterday test, we found that the RF amplifier for LO signal was broken. There was no spare at the electronic shop at Downs,

so we shorted the circuit for now.  Another part which was broken too was a transistor, Q3 PZT2222A, on D0901846.

It was removed and two connections, which are for Q3's 1 and 3 legs, are shorted. Now the voltages out from the regulators are back to normal.

 

We are checking a MAX333A switch, U6A on D0901894. it seems that the voltage that controls the switch disappears.

There might be a bad connection somewhere. This will be investigated next.

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