ESR meters and the Bob Parker unit revisited

[willawake]

Re: ESR meters and the Bob Parker unit revisited

thats a good price for the EVB unit.

[Per Hansson]

Re: ESR meters and the Bob Parker unit revisited

Is the EVB unit the black one with red LED and kinda blocky design?
If so that's the one I have and that is a very very good price for it!
Hope you like it when you get it, I sure love mine!

Thanks Bob Parker!

[Bob Parker]

Re: ESR meters and the Bob Parker unit revisited

Is the EVB unit the black one with red LED and kinda blocky design?
If so that's the one I have and that is a very very good price for it!
Hope you like it when you get it, I sure love mine!

There are pictures of the various versions at http://members.ozemail.com.au/~bobpar/esrmeter.htm

Thanks Bob Parker!

You're extremely welcome. I'm not used to getting this kind of attention.

[willawake]

Re: ESR meters and the Bob Parker unit revisited

i can only compare the EVB and the Blue units.
The EVB has a few problems : the two parts of the case are attached with plastic tabs. if you are not careful it is possible to break them. The button has a plastic tube on it which makes it reach the hole in the case. this can get pushed down a bit and then the button doesnt work too good. To change or remove the battery need to open the case.

These could all be solved by getting a new case and installing a new button. The EVB comes without probes so these need to be purchased to measure caps in circuit. it may be possible to use leads from a multimeter if they fit.

The EVB has high voltage protection.

The Blue doesnt have any of the problems. but it can tolerate moderate currents not 400v. leads are included but not the probe ends or alligator clips which are extra. it would be possible to use the unit without these as the leads have plugs on them. but that wouldnt be optimal.

in usage the units are identical.

[Bob Parker]

Re: ESR meters and the Bob Parker unit revisited

Anatek told me that the Blue meter is so tough that it's possible to grab its leads, swing it over your head and smash it onto a bench and it will still work! I haven't tried it, but that plastic case is very tough and it seems believable.

[willawake]

Re: ESR meters and the Bob Parker unit revisited

shit i just tried that and i broke my meter. thanks

[Krankshaft]

Re: ESR meters and the Bob Parker unit revisited

The EVB has a few problems : the two parts of the case are attached with plastic tabs. if you are not careful it is possible to break them. The button has a plastic tube on it which makes it reach the hole in the case. this can get pushed down a bit and then the button doesnt work too good. To change or remove the battery need to open the case.

These could all be solved by getting a new case and installing a new button.

From pics I've seen the EVB also uses Lelon caps and some other brand I can't remember. Sure they're not under any real stress and will probably be fine. But there is something ironic about checking for bad caps with bad caps .

While the blue uses Nichicons all around.

[Bob Parker]

Re: ESR meters and the Bob Parker unit revisited

The electrolytic caps in the ESR meter are working at room temperature with only a tiny level of ripple current, for short periods. They have a real easy life (except in the meter which Willawake smashed. ) compared to the unfortunate ones in hot-running switching power supplies and motherboard CPU voltage regulators etc. So it's unlikely that they will cause any problems for a very long time, if ever.

[sofTest]

Re: ESR meters and the Bob Parker unit revisited

The EVB has a few problems : the two parts of the case are attached with plastic tabs. if you are not careful it is possible to break them. The button has a plastic tube on it which makes it reach the hole in the case. this can get pushed down a bit and then the button doesnt work too good. To change or remove the battery need to open the case.

These could all be solved by getting a new case and installing a new button.

I either of this problems should surface, a cable tie around the unit and a drop of glue for the button tube would solve it for me.

And yes, thanks to Bob Parker for making this affordable design available.

[Per Hansson]

Re: ESR meters and the Bob Parker unit revisited

A cheers, then the one I have is this one "Dick Smith Electronics K-7214 kit"
I really enjoyed assembling the kit, sorry to hear they stopped selling that one
Anyway, good luck with your ESR meters!

[Huckfinn]

Re: ESR meters and the Bob Parker unit revisited

KeriJane and other kit builders:

I hope you have fun building the Blue ESR kit. I really enjoyed building my kit.

On the same subject, I have some tips for those of you on the Badcaps Forum who haven't assembled kits of this type before. [If these tips do not apply to you, just skim over this stuff].

While a temperature controlled soldering pencil [or "handpiece" as we call them in the pro grades] would be nice, for the purposes of the Blue ESR kit, a basic low cost 15 Watt soldering pencil [small iron] will do OK. If you have not done much soldering of small line width new copper foil PC boards, practicing first on a practice board with practice components is quite helpful in getting a much better result from your main meter project. If you have access to a Radio Shack or equivalent store, they have some real nice small line width pre-etched PC boards that are used in prototyping work, and most of them are low in cost. Radio Shack also has lots of small transistors, etc.. in small packs to use for practice at low cost.

For my unit, I chose not to use the included sockets from the kit, but substituted some nicer gold plated machined contact sockets made by the likes of Augat or Mill-Max. The socket strips furnished with the kit for the displays are actually the machined contact style that I like, however the ones included with my kit were not gold plated, so I subbed gold plated ones. The "wiping contact style" sockets for the two IC chips that came in my kit were not as good as a machined contact style so I also subbed those out. In obtaining gold plated machined contact sockets, keep in mind that you can use the exact socket size you need OR cut from a socket strip and place two rows of the correct number in the PC board holes. For my meter, I used a similar socket strip to the ones furnished in the kit, but with two improvements. I used gold plated in place of the ones provided,and I used a LONGER strip along the bottom in the display area so that the strip covers ALL of the holes, including the holes for the blue led decimal points. I can plug in both digital display units, both decimal leds, and both IC chips without having to expose thermally sensitive blue leds and thermally sensitive IC chips to the soldering process. Now it is true that soldering in components gives a better connection than your average low cost "wiping contact" style socket, BUT a gold plated machined contact socket [or socket made up of two strip rows] gives as good a connection as soldering, but WITHOUT the heat stress to components that soldering causes. The rest of the components will tolerate soldering better than the ICs and display pieces, provided you do not go "gonzo" with the heating process.[What is or is not "gonzo" of course is a matter of experience]. Also keep in mind that if an IC should get damaged due to a transient spike from a cap or static electricity, changing the IC out is MUCH easier when it is in a nice quality socket.

The assembly manual is very good for this meter, however, read it over first a couple of times before proceeding. If you have any doubts, or some of the steps do not seem clear, PM me or Bob Parker and get more info, so you can proceed with confidence.

For those of you that have temperature controlled soldering equipment, I suggest a setting of around 620 degrees Fahrenheit [ about 320 degrees Centigrade]. Use only high quality electronic grade solder, NOT acid core plumbing or craft grade! Carefully check the orientation of components before soldering them to the board [or plugging them in]. Polarity and orientation matters on electrolytic caps [ one electrolytic , C6 is bipolar and can be placed without regard to polarity orientation]. Orientation matters on both IC chips, both display digits, and both decimal leds. [All of these can be mistakenly installed 180 degrees flipped]. Orientation is not relevant on resistors and the non-electrolytic capacitors. Also, do not mix up the correct positions of the two trimmer resistors, they are of different values.

Have fun building the kit!

Huck

[KeriJane]

Re: ESR meters and the Bob Parker unit revisited

Thank you Huckfinn.

I'll try my best. I do have a temperature controlled iron and a handy Weller 18w "Pro Series" iron with a headlight in it.
http://www.cooperhandtools.com/brand...c=037103227348

Probably I'll use the temp controlled one as you suggest.

Have Fun,
Keri

[Huckfinn]

Re: ESR meters and the Bob Parker unit revisited

KeriJane;

That is a really neat Weller unit, however 900 F with a 60W equivalent performance might de-laminate the copper from the PC board. You are correct in picking your Temp. controlled unit to use on this project. The foil runs are rather delicate, but certainly do the job well for this meter.

Huck

[Bob Parker]

Re: ESR meters and the Bob Parker unit revisited

It should be made illegal to use uncontrolled temperature soldering irons on circuit boards. Or to operate temperature-controlled ones at temperatures far above or below what's appropriate.

Building the ESR meter isn't rocket science and it's not hard. As boards go, it's quite a simple one. Just get in there with a reasonably small controlled iron at about 340 degrees C, double check the position and orientation of the components including measuring the 1% resistors with a meter to confirm their value, and solder them in place with appropriate electronics grade solder.

Clip off the component wires after soldering (not before because the mechanical shock can damage some parts). Always lift the iron tip vertically away from the joint; don't 'wipe' it sideways because that makes solder whiskers which cause many problems. Pay attention that you're not accidently bridging separate solder pads with molten solder. Make sure you've earthed yourself before handling the static-sensitive displays, LEDs and ICs.

When you've finished, examine the copper side of the board with a magnifier and fix any joints that aren't perfect. If you've been half-way careful, it will work first time.

If after calibration the meter can read the 5.6 ohn and 82 ohm test resistors reasonably accurately and zero out the test lead resistance, there's nothing wrong and you can start checking all those suspect electrolytic caps you've been saving for this moment.

Don't try out the self-diagnostic function unless you really need to. And don't use a 9V battery with the diagnostic function because it will report an 'F2' fault which probably doesn't exist. It must be powered by 6.5V to work properly.

Good luck.

[Krankshaft]

Re: ESR meters and the Bob Parker unit revisited

Don't try out the self-diagnostic function unless you really need to. And don't use a 9V battery with the diagnostic function because it will report an 'F2' fault which probably doesn't exist. It must be powered by 6.5V to work properly.

Good luck.

Yeah for the heck of it I ran that diagnostic function off the battery and got the same error code . Did some digging in the manual and it said what you just did.

Plugged it into my bench supply dialed in the proper voltage and got the all good code (can't remember what it was).

[Bob Parker]

Re: ESR meters and the Bob Parker unit revisited

Yeah for the heck of it I ran that diagnostic function off the battery and got the same error code . Did some digging in the manual and it said what you just did.

Plugged it into my bench supply dialed in the proper voltage and got the all good code (can't remember what it was).

If the microcontroller is happy with the things it can check, all you'll see is the displays go blank for a fraction of a second, followed by all display segments and both LEDs turning on for a couple of seconds (which shows up any which aren't working), and then it turns off.

[KeriJane]

Re: ESR meters and the Bob Parker unit revisited

Yay!

I got the Blue ESR kit today.

I put it together, tested it and calibrated it all in one night.

It seems to work ok, right from the start.

It seems that I only got one IC socket, so that's all I used.

Testing a few of the OST caps I recently pulled out of a Shuttle revealed a reading of .02 on most of them. I think that's probably ok, isn't it?

A blowed-up Fuhjyyu read "- " Surprise!

Have a look at my clumsy amateur soldering.... though a bit crude, there aren't any bridges and not much flux residue. (really thin rosin core electronic solder was used)

Not having a handy variable power supply, the low battery warning was set to 6v supplied by two 2032 CMOS batteries instead of the recommended 5.5v.

The instructions are pretty good, but kind of skipped over some of the details.... I suppose that's ok as anyone building one of these things probably doesn't need all the details. The thing that almost tripped me up was the part where it said "(Do not install the integrated circuits until after performing the Initial Checks.)"...umm.... the "Initial Checks" section appears to be a power on test with the system fully together!

Another thing that almost fouled me up was that the board positions for the electrolytic caps are marked with a small "+" ... almost mistook that for a dot indicating negative. But I didn't.

It's a nice kit. Thank you, Bob Parker.

Have Fun,
Keri

[Huckfinn]

Re: ESR meters and the Bob Parker unit revisited

KeriJane:

The initial checks are indeed done with the unit assembled but without installing IC 2 and IC3. Once the initial checks come up as OK, the Zilog micro and the digital display driver IC are then installed and further items are checked. The reason for this order is that in case the kit builder makes a significant mistake, IC 2 & 3 will not get wiped out. The idea here is that if the initial checks fail, the kit builder will hunt down the problem so that the initial checks will pass, and IC 2 & 3 will be spared from damage.

A technique you can use to fine tune your low battery level adjustment is to use the two 3 volt lithium cells like you did, but add a regular plain silicon diode in series with your 6 volt source. A 1N4001 or equivalent will do. [ 1N4002 through 1N4007 etc... will also work just fine]. Connect the anode end to the plus side of your battery stack, and use the cathode end of the diode [the end marked with the paint band ] as your plus feed to the meter. The diode is biased on in this mode and will drop very close to a half of a volt across it, giving you a power source doggone close to 5.5 volts [and of course the negative end of the battery stack you connect as you did before]. The six volt supply [with a series diode to bring it to 5.5] can also be done with a four cell penlight battery holder with batteries.

Congrats on assembling the meter successfully!

Huck

[Huckfinn]

Re: ESR meters and the Bob Parker unit revisited

Blue ESR meter kit builders:

As an additional thought triggered by KeriJane's comment about probably not needing to consider all of the stuff in the assembly manual, I would have to say that in the case of this Blue meter, no superfluous stuff was included, so I advise heeding all of the instructions.

Huck

[Gianni]

Re: ESR meters and the Bob Parker unit revisited

Congratulations KeriJane

I jump in this thread to ask a question: it is enough to measure the cap ESR?
If I'm not wrong this "tester" measure only ESR and not cap value, so is it possible that a cap with bad value tolerance, let's say a 1000uF which is dropped at 600uF, has still an ESR within tolerance?
If this is possible, is it a limit to measure only ESR?

I hope I have not asked a stupid question.

Ciao
Gianni

P.S.: next time I change bad caps and I can measure their value I will check also the datasheet to check how much ESR/Value have changed from spec.