Anatek ESR Meter - VK1OD implementation

This article describes the VK1OD implementation of the Anatek 'Blue' ESR meter designed by Bob Parker.

The meter is designed to measure the equivalent series resistance of electrolytic capacitors.

The meter was purchased as a kit set from the Australian distributor Trans Electronics. The kit was complete (though some parts had different designations to the documentation), documentation was not included, and Trans Electronics were very slow in shipping the goods.

Fig 1:

Fig 1 shows the ESR meter in application, measuring the ESR of an old electrolytic capacitor.

Fig 2:

Fig 2 shows the component side of the assembled PCB. It can be seen that the PCB is single sided, and all simple through hole components.

Fig 3:

Fig 3 shows the solder side of the board. The assembled board has been cleaned and given a coat of acrylic clear PCB lacquer. Quite straightforward construction.

Basic use

The instrument was assembled, calibrated and tested. It seems quite reliable and straightforward in use. From the instruction manual:

1. Insert the probe terminator of your choice into the shrouded plugs. A croc clip works well for out of circuit
   capacitors, a probe for in-circuit.
2. Press the button so the “-” symbol appears on the display.
3. Hold the test probes tightly together – the test lead resistance is displayed.
4. With the probes still together, press the button again to give a zeroed reading of “.00”. You can repeat this at
   any time.
5. Measure the capacitor’s ESR (it should be discharged first). A reading of “-” indicates a reading greater than
   99!. Compare the reading to the graph on the front label. Good capacitors will have ESR below the graph lines,
   bad above.
6. When you’ve finished measuring, press the button with the probes separated. The meter switches off when
   you release the button.
7. When the battery is getting low, “b” flashes once per second and the display dims to conserve the remaining
   battery capacity.

Suggested improvements

All in all, a dated but good design well implemented. If anything, the wider use of switched mode power supplies makes the instrument more relevant than in earlier times.

 Nevertheless, some things I would suggest:

• Bootlace terminals are very effective in preventing conductor strands spreading under the screws of the supplied banana plugs.
• Provision for an external power jack for occasional users where the internal battery is just a nuisance. I have made a small adapter from the 216 cell header to a line 2.1mm DC jack and made a small notch om the cover to accommodate the adapter cable.
• Assembly instructions refer to parts designators (eg R10, R11 etc) but they are not marked on the PCB overlay, rather the values are shown. My preference is for the part designator.
• Update the instructions for the parts actually supplied.

Links

• Anatek
• Bob Parker's ESR page

Changes

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