Published By
Created On
1 Jan 2020 18:06:15 UTC
Transaction ID
Cost
Safe for Work
Free
Yes
#47 - Datron 1071 7.5-digit multimeter repair
A vintage metrology grade meter was repaired, calibrated and tested for stability. Not much was wrong with it: a couple of faulty caps, a stuck switch, and corrupt calibration data. The display is bad as well, but usable, so it can be tolerated for now. The loss of calibration is, of course, a big deal since I don't have appropriate equipment to calibrate a 7.5-digit meter, but I have done what I could given the circumstances. Then I run the meter together with HP 34401A for about 28 hours taking measurements of 10V from Fluke 341A calibrator over GPIB and plotting the data using Octave 4 with instrument-control package. The results look good: just a few ppm of drift over a wide temperature range, and the meters stayed within about 2.5 ppm from each other.
Forum: http://www.eevblog.com/forum/metrology/datron-1071-repair/
Datron 1071 Service Manual: https://drive.google.com/file/d/0B3NWgPtazb_tMUhKbkZpYXlUQTg/
Fluke 341A calibrator repair: https://youtu.be/mxz3-fGs1Lk
...
https://www.youtube.com/watch?v=jcCC867gKXE
Forum: http://www.eevblog.com/forum/metrology/datron-1071-repair/
Datron 1071 Service Manual: https://drive.google.com/file/d/0B3NWgPtazb_tMUhKbkZpYXlUQTg/
Fluke 341A calibrator repair: https://youtu.be/mxz3-fGs1Lk
...
https://www.youtube.com/watch?v=jcCC867gKXE
Author
Content Type
Unspecified
video/mp4
Language
Unspecified
More from the publisher
Controlling
VIDEO
#80 -
80-servicing-hp-8563e-spectrum-analyzer
This analyzer needed some servicing. The key pad had to be cleaned. And there was a hope that display focus could be improved, which did not quite happen, but it was not too bad. In the process some capacitors in the power supply were found to be bad, so all of them have been replaced.
EEVblog RIFA capacitors video: https://youtu.be/XAbrU17hLTM
...
https://www.youtube.com/watch?v=v9KSWkZIqzk
Transaction
Created
1 month ago
Content Type
Language
video/mp4
Controlling
VIDEO
#65 -
65-mackie-thump-th-12a-active-speaker
One of these Mackie speakers did not power up. The problem was traced to a pair of power diodes in a TO-220 package that had two pins broken off. I am quite puzzled as to how this happened. Perhaps, the speaker was dropped, and the board flexed so much due to relatively heavy transformer. Strange things happen.
...
https://www.youtube.com/watch?v=5zkEzjyKNjg
Transaction
Created
1 month ago
Content Type
Language
video/mp4
Controlling
VIDEO
#128
128-high-end-pioneer-elite-sc-09tx
This hi-end beast stopped turning on. It is very complex and weighs a ton. It was quite tricky to investigate the fault. Even a DSLogic USB logic analyzer by DreamSourceLab was used (perhaps was not necessary, but was fun anyway). It was found that the clock generator of the main MCU was not running. Also a reset was needed, which takes a secret combination of buttons on the front panel.
...
https://www.youtube.com/watch?v=-80m7mpBbhY
Transaction
Created
4 weeks ago
Content Type
Language
video/mp4
English
Controlling
VIDEO
#34 -
34-tektronix-tds-540a-oscilloscope
This scope suffered from the classic problem for this line: leaky electrolytic capacitors. All 96 capacitors were replaced, and a few broken PCB traces restored. A backup of Dallas DS1650Y NVRAM was made as well.
Schematics: http://hakanh.com/dl/kits.htm
Service manual: http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/TEK%20TDS%20520A,%20524A,%20540A,%20544A%20Service.pdf
Discussion: http://www.eevblog.com/forum/testgear/tektronix-tds-540a-repair/
Followup video: https://youtu.be/iJt2O5zaLRE
...
https://www.youtube.com/watch?v=7V0LCL4mL-8
Transaction
Created
1 month ago
Content Type
Language
video/mp4
Controlling
VIDEO
#16 -
16-cordoba-c5-ce-guitar-with-b-band-t35
I got a good deal on a great guitar Cordoba C5-CE, which is a classical guitar with a cutaway and electronics. I have seen several versions of this guitar made in different years and different places, and equipped with different preamps. This one has B-Band T35 preamp. The good deal was possible because the preamp didn't work. It turned out that someone messed up the electronics quite a bit. I was lucky that all essential parts still worked fine, so I managed to restore the guitar at no additional cost.
B-Band page about pickups and preamps: http://www.b-band.com/index.php?page=guitar-systems
Cordoba C5-CE page: http://cordobaguitars.com/p/c5-ce
...
https://www.youtube.com/watch?v=jK_VuPOakxQ
Transaction
Created
1 month ago
Content Type
Language
video/mp4
Controlling
VIDEO
#30 -
30-keithley-614-electrometer-repair-and
Vintage Keithley 614 electrometer was picked up on eBay as non-working. The unit was repaired and adjusted. The old-fashioned 2-lug triaxial connector on the front panel was replaced with a 3-lug one. The process was explained in some detail.
Discussion: http://www.eevblog.com/forum/testgear/keithley-614-electrometer/
Manual: http://exodus.poly.edu/~kurt/manuals/manuals/Keithley/KEI%20614%20Instruction.pdf
ESI DB-62 resistance decade box: http://www.ietlabs.com/esi-tegam-db62-decade-box.html
Agilent 34401A specs: http://cp.literature.agilent.com/litweb/pdf/5968-0162EN.pdf
...
https://www.youtube.com/watch?v=txH6EpqN5V0
Transaction
Created
1 month ago
Content Type
Language
video/mp4
Controlling
VIDEO
#5 -
5-agilent-6612c-repair-and-testing
Repairing of Agilent 6612C power supply, which was bought on eBay. It was sold "for parts or repair", and was cheap enough so that I couldn't resist.
Agilent 6612C key features:
Output ratings
Voltage: 0 to 20 V
Current: 0 to 2 A
Programming accuracy at 25°C ±5°C
Voltage: 10 m V
Current 0.05% + 1 mA
Ripple and noise (20 Hz to 20 MHz)
Voltage rms: 0.5 mV
Voltage Peak-to-Peak: 3 mV
Normal mode rms: 1 mA
Service manual: http://cp.literature.agilent.com/litweb/pdf/5962-8200.pdf
...
https://www.youtube.com/watch?v=HUSMUtIgP3E
Transaction
Created
1 month ago
Content Type
Language
video/mp4
Controlling
VIDEO
#141
141-krk-rokit-7-speaker-repair
The speaker did not power up. It turned out to be a very simple and boring electrolytic capacitor problem. At least we could take a look inside of this speaker.
...
https://www.youtube.com/watch?v=K3DhikDltEg
Transaction
Created
3 weeks ago
Content Type
Language
video/mp4
English
Controlling
VIDEO
#24 -
24-do-it-yourself-openevse-level-2
I built myself a level 2 charger for my Nissan Leaf explaining many details of the design and implementation in the process. It turned out that 2012 Nissan Leaf only takes 16A. The next step is to find an enclosure, and, perhaps, add more features like LCD display and current sensor. I am going to post a part two video soon.
OpenEVSE project page: https://code.google.com/p/open-evse/
Discussion: https://groups.google.com/forum/#!category-topic/openevse/general/duK18BFt8C8
Part 2: https://youtu.be/to4eYCJ4ZfM
...
https://www.youtube.com/watch?v=JVhBMvj4KuA
Transaction
Created
1 month ago
Content Type
Language
video/mp4