Mercurial > whatever / changeset

--- a/content/hp3562a.rst	Thu Nov 10 16:46:54 2022 +0100
+++ b/content/hp3562a.rst	Thu Nov 10 17:26:20 2022 +0100
@@ -29,6 +29,7 @@
 Here is the beast:
 
 .. image:: {static}/images/hp3562a/front.jpg
+   :alt: Front view of the HP3562A DSA
 
 I said the beast, because despite being an amazing piece of test
 equipment, it's also very big (576mm x 426mm x 222mm), very heavy
@@ -47,6 +48,7 @@
 as I know) with my device: the dimm display.
 
 .. image:: {static}/images/hp3562a/front_open.jpg
+   :alt: Inside the HP3562A DSA
 
 The unit consist in mostly 4 parts:
 
@@ -95,14 +97,17 @@
 
 
 .. image:: {static}/images/hp3562a/a18_psu.jpg
+   :alt: Picture of the HP3562A A18 PSU PCB board
 
 The primary capacitors are huge Sprague caps (1400µF 250V):
 
 .. image:: {static}/images/hp3562a/caps.jpg
+   :alt: Picture of the HP3562A main filter capacitors
 
 The power line filter is also pretty impressive:
 
 .. image:: {static}/images/hp3562a/filter.jpg
+   :alt: Picture of the HP3562A line filter module
 
 The PSU generates:
 

--- a/content/hp3562a_2.rst	Thu Nov 10 16:46:54 2022 +0100
+++ b/content/hp3562a_2.rst	Thu Nov 10 17:26:20 2022 +0100
@@ -20,6 +20,7 @@
 of small CPU for the time).
 
 .. image:: {static}/images/hp3562a/cpu.jpg
+   :alt: Picture of the main 68000 CPU of the HP3562A
 
 The 8 boards are:
 
@@ -52,6 +53,7 @@
 noise figures, bursts, sweeps, and so on.
 
 .. image:: {static}/images/hp3562a/a1_digital_source.jpg
+   :alt: Picture of the A1 Digital Source PCB of the HP3562A
 
 The Timing Control section looks like:
 
@@ -92,10 +94,12 @@
 processing of the instrument.
 
 .. image:: {static}/images/hp3562a/hp3562a_a2_block_diagram.png
+   :alt: Blocke diagram of the A2 board of the HP3562A
 
 The main CPU board, with the beautiful MC68000P9 DIP64 package:
 
 .. image:: {static}/images/hp3562a/a2_cpu.jpg
+   :alt: Picture of the A2 CPU board of the HP3562A
 
 It comes with 2 populated M5M256BP static ram chips (32k x 8bits), for
 the CPU, but seems to be capable of holding 4 more of them. The CPU
@@ -116,12 +120,14 @@
 ------
 
 .. image:: {static}/images/hp3562a/a38_memory.jpg
+   :alt: Picture of the A36 memory board of the HP3562A
 
 This board is described as an "extension of the read only memory of
 the system CPU board" and read/write memory used by most of the other
 assemblies.
 
 .. image:: {static}/images/hp3562a/hp3562a_a38_memory_block_diagram.png
+   :alt: Block diagram of the A38 memory board of the HP3562A
 
 The ROM section stores most programs for the HP 3562A except the
 startup routines (which are on the ROM ships of the A2 CPU
@@ -131,6 +137,7 @@
 used. ROM density is selected by placement of jumpers.
 
 .. image:: {static}/images/hp3562a/hp3562a_a38_rom_block_diagram.png
+   :alt: Block diagram of the RAM/ROM selection mecanism on the A38 board of the HP3562A
 
 
 The RAM section of the assembly consist of 4 32k by 8 bits static RAM
@@ -139,6 +146,7 @@
 Display, FPP and the system CPU).
 
 .. image:: {static}/images/hp3562a/hp3562a_a38_ram_block_diagram.png
+   :alt: Block diagram of the memory bus pipeline of the HP3562A
 
 The Display Controller section also lies on this A38 board.
 
@@ -154,9 +162,16 @@
 (synchronized with the sample rate). The sinusoidal signal is
 generated from a table of values stored in the ROM.
 
-.. image:: {static}/images/hp3562a/hp3562a_a4_block_diagram.png
+.. figure:: {static}/images/hp3562a/hp3562a_a4_block_diagram.png
+   :alt: Block diagram of the A4 local oscillator board of the HP3562A
+   
+   Block diagram of the A4 local oscillator board of the HP3562A
 
-.. image:: {static}/images/hp3562a/a4_loc.jpg
+
+.. figure:: {static}/images/hp3562a/a4_loc.jpg
+   :alt: Picture of the A4 bloard of the HP3562A
+   
+   Picture of the A4 bloard of the HP3562A
 
 
 
@@ -244,19 +259,29 @@
 FFT
 ---
 
-.. image:: {static}/images/hp3562a/hp3562a_a9_block_diagram.png
+.. figure:: {static}/images/hp3562a/hp3562a_a9_block_diagram.png
+   :alt: Block diagram of the A9 FFT board of the HP3562A
+   
+   Block diagram of the A9 FFT board
 
 The FFT board performs windowing, FFT and Inverse FFT directly from
 and to the RAM.
 It's built around a TMS230 microprocessor runningat 5MHz
 
-.. image:: {static}/images/hp3562a/a9_fft.jpg
+.. figure:: {static}/images/hp3562a/a9_fft.jpg
+   :alt: Picture of the A9 FFT board of the HP3562A
+   
+   Picture of the A9 FFT board
+
 
 
 Keyboard
 --------
 
-.. image:: {static}/images/hp3562a/hp3562a_a15_block_diagram.png
+.. figure:: {static}/images/hp3562a/hp3562a_a15_block_diagram.png
+   :alt: Block diagram of the keyboard processor
+   
+   Block diagram of the keyboard processor
 
 
 Next

--- a/content/hp3562a_4.rst	Thu Nov 10 16:46:54 2022 +0100
+++ b/content/hp3562a_4.rst	Thu Nov 10 17:26:20 2022 +0100
@@ -22,6 +22,7 @@
 dedicated display controller (which is on the A38 memory board):
 
 .. image:: {static}/images/hp3562a/a8_a17_display.png
+   :alt: Block diagrams of the HP1345A A8 and A17 boards
 
 The unit is a 6 inch monochrome display producing true vector graphics
 with a resolution of 2048x2018 points. It can display up to 3226
@@ -31,6 +32,7 @@
 on the screen (it's not a pixel based display).
 
 .. image:: {static}/images/hp3562a/hp1345a_raster_vector.png
+   :alt: Picture of the raster vs. vector display principle
 
 It can diplay:
 
@@ -51,20 +53,26 @@
 Allowing more brightness control of the vectors.
 
 .. image:: {static}/images/hp3562a/hp1345a.jpg
+   :alt: Picture of the HP1345A vector display module
 
 
 If not connected with a controller, it shows a test pattern for
 adjustments.
 
 .. image:: {static}/images/hp3562a/hp1345a_test_pattern.png
+   :alt: Picture of the HP1345A test pattern
 
 The unit looks like:
 
 .. image:: {static}/images/hp3562a/hp1345a_side.jpg
+   :alt: Picture of the HP1345A vector display module (side view)
 
 .. image:: {static}/images/hp3562a/hp1345a_side2.jpg
+   :alt: Picture of the HP1345A vector display module (side view)
+
 
 .. image:: {static}/images/hp3562a/hp1345a_top.jpg
+   :alt: Picture of the HP1345A vector display module (top view)
 
 
 Adjustment and repair
@@ -89,6 +97,7 @@
 to desolder (at least one end): A1C45 and A1C48.
 
 .. image:: {static}/images/hp3562a/hp1345a_dead_caps.jpg
+   :alt: Picture of the 2 shorted tantalum capacitors
 
 
 These 2 small (tantalum) caps near U3 were short. Not sure why they
@@ -111,13 +120,18 @@
 -----------------
 
 .. image:: {static}/images/hp3562a/hp1345a_block_diagram.png
+   :alt: General block diagram of the HP1345A display unit
 
 .. image:: {static}/images/hp3562a/hp1345a_stroke_generator.png
+   :alt: Block diagram of stroke generator of the HP1345A display unit
 
 
 .. image:: {static}/images/hp3562a/hp1345a_ramp_generator.png
+   :alt: Block diagram of the ramp generator of the HP1345A display unit
 
 
 .. image:: {static}/images/hp3562a/hp1345a_vector_processor.png
+   :alt: Block diagram of the vector processor of the HP1345A display unit
 
 .. image:: {static}/images/hp3562a/hp1345a_vpc_architecture.png
+   :alt: Block diagram of the VPC architecture of the HP1345A display unit

--- a/content/hp8662a.rst	Thu Nov 10 16:46:54 2022 +0100
+++ b/content/hp8662a.rst	Thu Nov 10 17:26:20 2022 +0100
@@ -44,6 +44,7 @@
 
 .. image:: {static}/images/hp8662a/dirty_hp.jpg
    :class: image-process-large-photo
+   :alt: Very dirty inside view of the HP8662A
 
 
 And I must say that if most of the unit is very easy to service due to the
@@ -54,17 +55,21 @@
 
 .. image:: {static}/images/hp8662a/top_before_2.jpg
    :class: image-process-large-photo
+   :alt: Top view of the inside of the HP8662A
 
 .. image:: {static}/images/hp8662a/bottom_before.jpg
    :class: image-process-large-photo
+   :alt: Bottom view of the inside of the HP8662A
 
 .. image:: {static}/images/hp8662a/front_after.jpg
    :class: image-process-large-photo
+   :alt: Fromt view of the inside of the HP8662A
 
 Also, there are hundreds of screws in this unit! it's insane.
 
 .. image:: {static}/images/hp8662a/top_after.jpg
    :class: image-process-large-photo
+   :alt: Top view of the many shielded compartments of the HP8662A
 
 Whatever, I finally got to a point I could clean most of the parts of the unit,
 so I started to reassemble it. Unfortunately, I did not took enough pictures
@@ -73,13 +78,15 @@
 
 .. image:: {static}/images/hp8662a/reassembling_2.jpg
    :class: image-process-large-photo
+   :alt: General view of the HP8662A case
 
-Once I had the structure of the generator back togother, with the back plane in
+Once I had the structure of the generator back together, with the back plane in
 place but no other board nor module plugged in, I started to take care of the
 PSU.
 
 .. image:: {static}/images/hp8662a/reassembling_1.jpg
    :class: image-process-large-photo
+   :alt: General view of the bottom of the HP8662A case with the main mother board
 
 The PSU
 =======
@@ -96,6 +103,7 @@
 
 .. image:: {static}/images/hp8662a/PSU_simplified_schematic.jpeg
    :class: image-process-large-photo
+   :alt: Simplified schematics of the HP8662A PSU
 
 The 4 boards the PSU is made of are:
 
@@ -116,6 +124,7 @@
 
 .. image:: {static}/images/hp8662a/PSU_block_diagram.jpeg
    :class: image-process-large-photo
+   :alt: Block diagram of the HP8662A PSU
 
 So I gave a close look at thes boards, beginning by the main board, the I found
 the culprit for the smoke: the input protection thermistor. Strangely, it still
@@ -128,6 +137,7 @@
 
 .. image:: {static}/images/hp8662a/smoking_thermistor.jpg
    :class: image-process-large-photo
+   :alt: Picture of the smoked thermistor
 
 After this first step forward, I was not confident enought to plug the boards
 back in place and try again (I am always worried when I repair switching
@@ -149,6 +159,7 @@
 
 .. image:: {static}/images/hp8662a/PSU_inverter_schematic.jpeg
    :class: image-process-large-photo
+   :alt: Full schematic of the PSU
 
 Looking at the schematics and the boards, I did find several failure points:
 
@@ -163,9 +174,11 @@
 
   .. image:: {static}/images/hp8662a/broken_choke.jpg
      :class: image-process-large-photo
+     :alt: Pictures of broken choke coils
 
   .. image:: {static}/images/hp8662a/replacement_choke.jpg
      :class: image-process-large-photo
+     :alt: Picture of the replacement choke coils
 
 - there are 2 small 400mA fuses on the inverter board to protect the base of
   the 2 switching (bipolar!) transistors (first time I see the base of an NPN
@@ -178,6 +191,7 @@
 
   .. image:: {static}/images/hp8662a/fuse_replacement.jpeg
      :class: image-process-large-photo
+     :alt: Picture of the hacked replacement fuse
 
 
 After these fixes, I reassembled the PSU and tried again: the result was quite

--- a/content/hp8662a_2.rst	Thu Nov 10 16:46:54 2022 +0100
+++ b/content/hp8662a_2.rst	Thu Nov 10 17:26:20 2022 +0100
@@ -27,6 +27,7 @@
 No surprise: these keys were missing their famous (well, for some at least) spring:
 
 .. image:: {static}/images/hp8662a/key_missing_springs.jpg
+   :alt: Picture of the 2 missing springs in the kayboard
    :class: image-process-large-photo
 
 As you can (not) see, the "Status" key as well as the "Increment Set" key have
@@ -50,9 +51,11 @@
 the same as original keys:
 
 .. image:: {static}/images/hp8662a/key_hack.jpeg
+   :alt: Picture of the spring replacement hack
    :class: image-process-large-photo
 
 .. image:: {static}/images/hp8662a/key_hack_anim.gif
+   :alt: Animated picture of the spring replacement hack
 
 I cleaned all keys using some deoxit contact cleaner which also lubricated
 those noisy springs making the keys nice ans smooth again.
@@ -72,3 +75,4 @@
 
 .. image:: {static}/images/hp8662a/encoder.jpeg
    :class: image-process-large-photo
+   :alt: Pictures of the rotary encoder