2022. január 26., szerda

HP E1300A Front binding posts 1.

Have you ever fall into the situation when you feel you have a quick and easy project, and at the day you realize it took tremendous amount of your time?

This is that kind of project.

Back to the beginning, I'm working on repairing, programming my HP E1300A VXI mainframes (actually I've three of it). The look of the front panel is a joke. A big beige panel with almost nothing on it.

The other thing I don't like on this instrument that it has binding posts for the integrated DMM just on the back side.

I don't want to modify the unit the way it can't be undone, but I need the binding posts to the front panel.

What I almost certainly know, I'll never use the space for the floppy drive for anything. The faceplate can be easily removed, and put something into it's place.

So I designed a small breakout board, with front panel, mounting hardware here. There were missing library parts, modules, 3D models in the KiCAD, first time used FreeCAD for the final assembly, made a millimeter misalignment during the design, and various additional problems. This made a week project from the one I planned for a single evening.

Here is the result:

I think there is not too much additional thing to write about it.

The design files are located here: 


I'm just thinking loudly. Is there a demand for this unit? Maybe it could be my attempt after a few years to sell one of my designs on the eBay or Tindie.

2022. január 20., csütörtök

Keithley 2001

 I bought a Keithley 2001 DMM 1,5 years ago. It has a problem: calibration lost.

Tried to extract the contents of the calibration EEPROM, unsuccessfully (finally I realized, that the type I configured on the TL866 was different, so I'll never know if the EEPROM was faulty or not), so I exchanged it to a new one. This time I also added a socket to it, so it will be easier to exchange next time.

Also burned a set of new EPROMs with the latest firmware available.

Added the Dallas NVRAM option. Later realized, that a cheaper, better option would be available:

Next time!

As you see the range down button is broken. Also time-to-time some buttons are stuck, when pressed.
Ordered a new front panel button set (https://pakahuszar.blogspot.com/2022/01/new-arrivals-2.html) and replaced it.

The multimeter looks up and running, except the calibration. I'm looking for a service to recalibrate it.

2022. január 19., szerda

New Arrivals 2.

As I planned, continue the new arrivals series

Keithley buttons

I've a Keithley 2001 multimeter. It had some issues with the front panel buttons. One broken, a few others stuck a bit when pushed. I ordered it long time ago. Unfortunately they sent a set for the 2000 one, what has different button labels.

As I also have Keithley 2000 multimeters I kept that one as spare part and reordered once again. Finally the correct one arrived.

I just bought a few J107 J-FETs, nothing interesting in it as such. I'm planning a rather interesting project with those what intend to solve one of my old electronics puzzles in my head.
Also bought 2A 6.3x32 fuses for the new power inlet module in the E1300A.
I made a mistake here. I checked the fuse holder in the old module, but the new use 5x20 fuses:

Keithley 2010 / HP 34401A
This was a local catch. Found a Keithley 2010 and a HP 34401A multimeter locally. Fortunately below the eBay prices. Had not enough time to test them yet. But the first tests looks promising.

2022. január 8., szombat

New arrivals 1.

I decided to write a "mailbag" like posts.
Here is the first one.
What arrived recently.
As I wrote previously, the mains inlet of the E1300A VXI mainframe blown. The replacement arrived. Unfortunately I got one out of the ordered two. I plan to install it in the next few days.

The boards for the USB-RS232 and the new USB-GPIB arrived. Not yet know, when can I build from it.

A local catch. I bought a "few" Kingbright 15x15mm four element LED bars. Altogether more than 500pcs. It was around ¢15 each. I don't have too much idea what to build from it yet (just some cloudy ones).

This is for this week (I intend to continue on the next)

2022. január 4., kedd

HP E1300A - EPIC Fail

In the last few days I was working on my instrument control software. I wanted to test, what I achieved with an SCPI compliant device also (now I mainly use my Keithley 199 DMM for the tests).

The first SCPI compliant device I found around is a HP E1300A B-size WXI mainframe with DMM and switch cards (I've three of this).

First I wanted to clean it up, repair if it necessary.

(Read further, text continue after the first set of pictures)

Everything is clean, the dead battery pack exchanged to a battery holder. The only thing still need exchange the old Papst fan. Actually the same fan still in production but it cost insane $60 (I got the two E1300A units as a gift, and bought my first one for  $15). This one if it is new has 36dB noise level. I found a Noctua model, with the same airflow 17dB noise level. I know it is not the "industrial" one, but the unit will be lightly used in my lab, so it will be good enough. Even the fan isn't installed yet.

Just for the try switched on the unit connected a GPIB adapter and checked if I can communicate with it. Looks everything fine after assembly.

Switched off the unit and went to the bathroom. I hear some weird noise from there. Went back to my room. Thick smoke coming out from the switched off unit and stinking like hell. Pulled out the mains cable and didn't understand what happened.

Disassembled the whole unit once more:

The filter in the mains outlet blown.

At least this indicate, that probably the unit itself doesn't has further issues as result of this failure.

New outlet ordered, I'll finish the assembly when arrived.