• sam. 20 janvier 2018

    EIP 545B RF Frequency Counter - Part 2

    I've started a discussion on the eevblog forum to gather a bit help for my project. And I did well since a few fellows did help me a lot on some aspects.

    I have now been able to run the power meter at full resolution (even if it's very out …

    • mer. 20 décembre 2017

      EIP 545B RF Frequency Counter

      I recently purchased a broken EIP 545B microwave frequency counter on ebay. It was very inexpensive (around 150€ delivered), but obviously, non working.

      The EIP 545B RF Counter

      The device was described as "does not power up", an is clearly not in very good condition. Quite dirty, battered, with the band 2 BNC connector ruined …

      • ven. 22 septembre 2017

        HP ZR24W PSU Repair

        A friend of mine had a problem with his (a bit old) 24" HP monitor: the device was working properly, but only for a while (few minutes at most).

        Looked like a good candidate for a quick repair, problem being most probably bad caps are so.

        The first step was …

        • mar. 03 janvier 2017

          HP3562A Dynamic Signal Analyzer

          One of my old test gears waiting for my attention in the cellar was a HP 3562A Dynamic Signal Analyzer. Back then I bought this device mainly for doing audio analysis (I was building my HiFi system, mostly based on Nelson Pass' schematics), mainly to display spectrum responses and compute …

          • mar. 03 janvier 2017

            HP3562A Dynamic Signal Analyzer - Part 2

            This is the part 2 of the series about my HP 3562A Digital Signal Analyzer, quickly describing the Digital Section of the instrument.

            Digital Section

            The unit is quite capable, since the main CPU is a 68000 (not exactly of small CPU for the time).

            The 8 boards are:

            • A1 …

            • mar. 03 janvier 2017

              HP3562A Dynamic Signal Analyzer - Part 3

              This is the part 3 of the series about my HP 3562A Digital Signal Analyzer, quickly describing the Analog Section of the instrument.

              Analog Section

              The analog section consist in 6 boards:

              • A30: Analog Source
              • A31: Trigger
              • A32, A34: Input ADCs
              • A33, A35: Input

              Analog Source

              This board is mainly …

              • mar. 03 janvier 2017

                HP3562A Dynamic Signal Analyzer - Part 4

                This is the part 4 of the series about my HP 3562A Digital Signal Analyzer, quickly describing the HP 1345A Digital Display unit as well as the repair I had to do on it.

                Display

                The display unit is a HP1345A Digital Display without the option 714 (wich adds a …

                • mar. 22 novembre 2016

                  HP 3456A Digital Voltmeter

                  A very long time ago, I bought a venerable HP 3456A Digital Voltmeter. Back then, I had no clear idea what kind of device it is; but it was cheap. It worked quite fine (it is indeed not calibrated), but I noticed for a while that it was quite unstable …

                  • dim. 18 septembre 2016

                    HP 34970A Data Acquisition Unit - communication protocol

                    In order to build a replacement display for the HP34970A data acquisition unit, I needed to understand the communication protocol between the CPU board and the front panel assembly.

                    General description

                    The unit is built with four boards:

                    • A1 is the main bard, with the PSU, the main controller and …

                    • sam. 17 septembre 2016

                      HP 34970A Data Acquisition Unit - part 4

                      After a summer pause, I'm back on my HP34970A replair project. In the previous post in this series, I've started to reverse ingineer the serial protocol between the CPU board and the fonrt panel, and implement a prototype of replacement display.

                      OLED display

                      I bought the bigest OLED display I …

                    « Page 2 / 4 »