Finally built the Bob Parker "Blue" ESR Meter

[jayjr1105]

Have wanted to build this for a long time ever since I saw Dave Jones use the old black and red one. It was fun to build and works great. What ESR meters do you guys use?

[Per Hansson]

There have been a few threads about this meter in the past if you want some history.
I still have mine, and I used it today at work!
Sure I have a couple of the Atmega based "transistor testers" that are all over eBay.
But this original Bob Parker design is special to me, I really like it!

https://www.badcaps.net/forum/showthread.php?t=1287
https://www.badcaps.net/forum/showthread.php?t=6535

[stj]

i didnt even know the Anatek blue was still being sold!

[jayjr1105]

Oh wow, the Bob Parker lurked on these forums, cool!

I love it. Just waiting on better probes. Wish the blue meter had the banana jacks like the old Dick Smith model had. Otherwise It's great and was fun to assemble.

[stj]

you could re-drill the endplate and fit a couple of 4mm shielded sockets.

[jayjr1105]

Originally Posted by stj

you could re-drill the endplate and fit a couple of 4mm shielded sockets.

They actually give you an extra endplate without any holes, I guess in case you want to do something like this. You'd have to re drill the hole for the power button but that's not difficult.

[redwire]

The Blue ESR Meter works great for me, it just plain works with no hassles and a good investment.

The Zilog Z8 MCU is obsolete and I wondered about the kit's supply.
I wanted to write firmware take the concept over to a newer MCU and find a way to add an extra digit, and read capacitance as well.

[jayjr1105]

Is the original code used for the Z8 closed source?

[stj]

i think so.

[bcstedt]

Thanks for the update and the pics!

I mostly use the Blue ESR (rev 1) and the DE-5000 (ver 8). I just got looking over the Blue ESR docs and found the self test section (it's been a long while) but have now found my meter is giving an FA error code. Can anyone else confirm their self test is working okay (.8.8 display)?

I've never noticed anything really 'strange' about the behaviour of my Blue ESR but now I'm curious. :/



From the manual:

Switch the meter on by pressing and continuing to hold the button down, regardless of what the displays are showing. After five seconds, they will go blank for a moment and then show a test result for two seconds. The meter will then switch off by itself after you release the button.

If everything is more or less OK, you’ll see “.8.8” on the displays (this shows that all the display segments and decimal point LEDs are working). However, if the microcontroller has detected a problem it will flash a fault code
consisting of an “F” on the left hand display and a character from 0-9 or an “A” on the right hand one.

...

FA: Q6 not switching on. Check around Q6 (2N3904), R24 (10kΩ) and pin 1 of IC2.

The microcontroller cannot perform detailed tests on every component, so it’s possible that your meter is malfunctioning even though the self-testing hasn’t shown up a problem. For example, if the meter is behaving strangely, “freezing” up or giving absurd readings on some values of test resistors, the most likely cause is a mix-up in the values of R6 (10kΩ), R8 (1kΩ) and R10 (100Ω). On the other hand, if the meter produces readings but there’s something wrong with the displayed characters, this is almost certainly due to one or more solder bridges between the pins of the displays or around IC3.

[Per Hansson]

Mine (an original Dick Smith Electronics K-7214 MK2) shows 8.8 for the self-test.
It could be that Q6 has been damaged from a charged capacitor.
You can check the area around it and ultimately try to replace Q6.

[bcstedt]

I've inspeced the board, checked the battery and voltage while running, reseated the Zilog (IC2) but no change. A damaged Q6 seems like a reasonable explanation I'm just surprised. :|

[redwire]

The Blue ESR meter firmware does show fault codes for many problems:
F0- Q11 not discharging Q10.
F1- C10 charging too fast.
F2- C10 charging too slow or not at all.
F3- Pulse amplifier bias Q8-C <0.44V
F4- Pulse amplifier bias Q8-C >1V
F5- Test current source is always on.
F6- Pulse amplifier has no output.
F7- Q3 not sourcing current.
F8- Q4 not sourcing current.
F9- Q5 not sourcing current.
FA- Q6 not switching on.


FA might be the input protection diodes D3 or D4 shorted. Those fail if you connect the unit to a big charged cap. Less likely the 22uF BP cap C6 has gone open.

[jayjr1105]

Bought some cheap modular probes for mine. Thinking about soldering in some thicker/longer wires into it, the ones that came with this probe kit to be exact. Probably don't want them too long right?

[stj]

huge probes!
i have several of these - i get a pair for every meter!
https://www.aliexpress.com/item/32848907433.html

[bcstedt]

Q6, D3 and D4 are not shorted and seem to test ok in circuit.
C6 measures 22uF in both directions, also in circuit.

Prefer not to remove components until I have a better idea what's going on. Maybe I'll see if I can contact Bob.

[bcstedt]

Originally Posted by stj

i have several of these - i get a pair for every meter!
https://www.aliexpress.com/item/32848907433.html

Those look pretty neat especially for the price. Do you use this seller specifically?

[bcstedt]

Component locations for those playing along.

[jayjr1105]

Originally Posted by bcstedt

Those look pretty neat especially for the price. Do you use this seller specifically?

Probemasters are some of the best probes you can buy and they are like $15 shipped. Highly recommend them.

[jayjr1105]

Originally Posted by stj

huge probes!
i have several of these - i get a pair for every meter!
https://www.aliexpress.com/item/32848907433.html

Not a ton of options when you need modular ones that will accept 4mm banana plugs.