Find great deals for Datron DIGIT Selfcal Digital Multimeter – Faulty. Shop with confidence on eBay!. Wavetek/Datron Multi-Product Calibrator .. The from Wavetek/Datron is a high performance, 8½ digit bench top multimeter. It can measure direct voltage. Datron repair. «on: January 26, , am». Hey. «Last Edit: February 02, , am by whatamidoing». Logged.
|Published (Last):||1 April 2015|
|PDF File Size:||19.56 Mb|
|ePub File Size:||4.51 Mb|
|Price:||Free* [*Free Regsitration Required]|
Possibly one of the daughterboards was failing? After going over all cable connections nothing obvious was found.
It appears that the two outside connectors were placed in the opposite location. Its voltage was measured at 3.
Heatshrink was added to the P and N wires. It is the same make as the first but an adapter board had been designed with FRAM so it was going to be installed in this meter first after it has been tested.
All information posted here is hosted just for education purposes and provided AS IS. It was also found that a plastic spacer dattron sits between the board and one of the standoffs was no longer in place.
DATRON 1281 8.5 DIGIT Selfcal Digital Multimeter
Replacement of battery was performed with unit powered on and a battery powered soldering iron was used to avoid loosing calibration constants and SRAM data. In out units refereces were enclosed in black epoxy, and would be troublesome to remove from PCB for teardown.
The serial number was still correct as was the line frequency, as expected. Patent data Secondary outputs of this low voltage transformer are rectified and regulated with usual LDO s to provide clean analog supply voltages. Both meters show zero errors after tests. The remaining capacitors had no additional gotchas. While testing optocouplers with second Datronit was noticed that error codes were different on second meter if optocouplers were left out of circuit.
Other repairs The lithium battery was not replaced.
Datron 1281 8.5 DIGIT Selfcal Digital Multimeter – Faulty
Paint on handles did not last well, having visible peeling now. The current source was tested using Keithley Model as control meter. Most likely the calibration constants are too far off. But first things first, power supply checks. During reassembly of the bottom half of the meter, it was discovered that the Current assembly had some difficulty with the three connectors at the front of the pcb.
Datron photos CH amplifier. Decision to make this article public was done to aid other owners of these precision multimeters from Datron. A quick reconnection and all the ranges appeared to respond as expected with the short on the input. All but two capacitors were replaced on the DC board 12 of If you do have any questions, jump in comments! The Ohms assy was installed in the previous and a fast self-test was performed without errors. It looked good with the input shorted, however the OHM s readings were open.
All tests completed now without errors. Error was added after repairing Digital and DC assys. No signs of burning though.
Datron DIGIT Selfcal Digital Multimeter – Faulty | eBay
Testing Steps If the instrument is smoking or has a bad smell coming from it turn it off immediately and contact us for further instruction. Looks at all those transformers!
Service manual decode message for states: Testing should only be performed by qualified technicians. The other two capacitors were surrounded by other parts preventing them from being changed easily. All seven capacitors were changed with only one gotcha.
Meter was failing with error message — C03 immediately after power on. No issues with front panel or display.
| Datron DMM repair and calibration worklog
All the feedback is valued and can be added into article. Age — Very old instruments can suffer from age related failures caused by normal deterioration of components and assemblies over time. Normal 128 1k resistor gain noise.
That likely caused some excessive currents flow thru webs and poor bug, causing measurement issues.
Compressed air was used to clean the dust and debris from the DC pcb. Not good, as this shows someone was diagnosing an issue that required the board to be possibly removed from the frame. Fuse Tests Fuse is open circuit. The Digital board, however, has no markings and does not match the component layout datroj in the service manual. All credits with discussion and raw content, photographs and testing go to him.
The original three errors were gone, but a new error had been added from the Datrln assy. DMM rear face Teardown Datron and lesser brother using interesting arrangement for primary power supply with two big toroidal transformers.
No repair required here. It is even more amazing to see just few problems with both DMM s, most of which were resolved after simple capacitor replacement and reassembly. A quick test of the inguard supplies on the DC board showed the following values: Power up the and let it warm up for 30 minutes. There are no official man manufacturer service for this old DMM s anymore, so hopefully we will not need custom unobtainable components, as that can easily put repair into BER.
DMM rear face Display: A few solder joints on the board were suspicious and reflowed.