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Message ID: 1955     Entry time: Mon Oct 23 15:11:50 2017
Author: Craig 
Type: DailyProgress 
Category: FSS 
Subject: North TTFSS Box Common Path Feedback Resistor Repaired 

Today I was starting measurements of the North TTFSS, when I noticed that the 100Ω metal film feedback resistor on the Common Path was bent (R3 on the TTFSS Common Path schematic).  When I touched it further, the pad it was soldered to came out.  I believe this is the cause of awade's poor measurements of the North TTFSS this weekend.

I repaired the North TTFSS by soldering a 100Ω black surface mount resistor that was taped inside the box into the feedback resistor spot, and connecting everything with a hunk of solder.  Not the best practice, but it works even though the pad and trace from R5 to R3 is gone.
 

Attachment 1: NorthCommonPath_FeedbackResistorGone.jpg  1.689 MB  | Hide | Hide all
NorthCommonPath_FeedbackResistorGone.jpg
Attachment 2: NorthCommonPath_FeedbackResistorPostRepair.jpg  1.459 MB  | Hide | Hide all
NorthCommonPath_FeedbackResistorPostRepair.jpg
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