--- a/content/hp3456a.rst Wed Oct 16 21:52:38 2019 +0200 +++ b/content/hp3456a.rst Wed Oct 16 21:53:47 2019 +0200 @@ -30,7 +30,7 @@ but the readings were quite disappointing. I was considering implementing a signature analyzer using a Nucleo STM32 board, since I have several of them for my `HP 34970A display replacement project -<{filename}/hp34970a.rst>`_. +<{static}/hp34970a.rst>`_. Suddenly, I realized I did not even check the power rails! And bingo, the +33V was dead (something like 5V). @@ -38,20 +38,20 @@ Ok, much better, a power supply failure is a way better news. Especially since this kind of device uses a linear power supply: -.. image:: {filename}/images/hp3456a/psu.jpg +.. image:: {static}/images/hp3456a/psu.jpg :alt: HP 3456A's power supply board Yes, it is very dusty. The culprit appeared in plain sight as soon as I removed the power supply board (A10) from the unit: -.. image:: {filename}/images/hp3456a/psu_C7.jpg +.. image:: {static}/images/hp3456a/psu_C7.jpg :alt: failing caps on HP 3456A's power supply The schematic is very straighforward; few bridge rectifiers, some capatcitors, some regultators, nothing fancy: -.. image:: {filename}/images/hp3456a/psu_schematic.svg +.. image:: {static}/images/hp3456a/psu_schematic.svg :alt: schematic of the power supply board The dead capacitor is C7 (47µF, 50V, Sprague). I also checked the @@ -69,19 +69,19 @@ Whatever, after this quick recap, the 3456A is back alive: -.. image:: {filename}/images/hp3456a/1.0011v.jpg +.. image:: {static}/images/hp3456a/1.0011v.jpg :alt: 1.0011V And even better, it look much more stable than it used to be! For example, here a plot of my Geller Voltage Reference a few month ago: -.. image:: {filename}/images/hp3456a/geller_2016_02.svg +.. image:: {static}/images/hp3456a/geller_2016_02.svg :alt: 10V and now: -.. image:: {filename}/images/hp3456a/geller_2016_11.svg +.. image:: {static}/images/hp3456a/geller_2016_11.svg :alt: 10V