Bob Parker ESR Meters

[Bob Parker]

Re: Silicone Chip's ESR meter kit @ DSE (AUS)

Just picked mine up (thanks for the tip), shop assistant said the $79.95 -> $24.95 price drop reflected the low interest in this particular kit project, hence it was his belief that this was a product run out special

So folks... come get 'em while they're HOT!

"Low interest"....? The guy's a fool. It's simply because DSE's management has made the executive decision to stop production of all kits and they're trying to get them all out the door so they can use the space for more phone answering machines, MP3 players and vacuum cleaners.
There's still a lot of interest in ESR meters!!

[Bob Parker]

Re: EVB ESR Meter (Bob Parker Design)

Humm a quick look at the meter comparison at Anatek reveled this....

Not sure if its in ref to MKI or MKII Kit maybe both



They were not specific as to what this "degradation in the components" was?
(apart from "Good, quality of components has degraded recently")

Still at $80 AU it might be something to winge about at $25 AU guess not

Anatek Comparison of ESR Meters HERE

Suppose the short answer is replace any parts you consider are lower quality with a better spec device.
If you think it really needs it.


I didn't see this info till now or other wise I would have posted it along with the original post on the $25 deal

All that's 'degraded' that I know about is that the 7 segment displays they've put in recent kits aren't very bright. For those lucky enough to be in the USA, Mouser Electronics sells Kingbright SC56-11EWA ones for about $1 each, which should be much better and they just plug into the socket.
I'm not sure if they're available Down Under....

[Bob Parker]

Re: EVB ESR Meter (Bob Parker Design)

welcome to crapcapland Bob!

thanks for designing the meter it brings troubleshooting to another level.

As I told kc8adu, I've been looking at what's going on here whenever I see a lot of visitors to my ESR meter web page coming from this forum. He talked me into joining up, so you can blame him for me making a pest of myself here!!
Before I forget, I really appreciate the nice things people have been saying about the little ESR meter I designed way back in the middle of 1995. It's that old now! Thanks!

[willawake]

Re: EVB ESR Meter (Bob Parker Design)

welcome to crapcapland Bob!

thanks for designing the meter it brings troubleshooting to another level.

[Spacedye69]

Re: EVB ESR Meter (Bob Parker Design)

Thanks for the info, Bob!

[Bob Parker]

Re: EVB ESR Meter (Bob Parker Design)

I will agree about the probes. The jacks seem to be pretty good, but the tension on the banana plug is low and the do not make a stable conection. I have to hold real still and wait 5-10 sec for the reading to stabilize.

If you've got some completely-evaporating contact cleaner like CRC CO, spray it all over the plugs and jiggle them around in the jacks before it evaporates. That usually helps. Also give the probe tips a brushing with a wire brush occasionally.
The problem is that on the bottom range, the meter's reading 1/100ths of an ohm, and varying contact resistance shows up real bad.

[starfury1]

Re: EVB ESR Meter (Bob Parker Design)

Hi all

Yes gdement you are right re the silkscreen being a mod for MKII according to info

Sorry to hear of your drama's

I have Both MKI MKII

The MKII I bought first few months ago see pics on page 2 its is marked as the MKII version PCB (10/03)
I think I got a dud cause it didn't have holes for the 220 uF Cap either
(I had to mount it on the back)
I paid $70 odd AU for it..it was $10 off normal price if memory serves me.

I bought the MKI for the fire Sale price it was the last one in the shop.

I don't think there is any component or circuit changes
(Haven't absolutely checked thought)

Apart from I knew firmware and the use of 1V5 batteries as opposed to the 9V one used in the MKI

MKII is the improved version of the MKI

As to your problems with the bannana leads, well see if you can source better quality plugs or leads is one idea.

If you go the other way, use a grommeted hole and a stain relief clip or you could possibly try on of those screw down cord clamps but you may not have enough room for one on them I think.

The zero function should take care of any spurious capacitance etc with the leads

if you want a pic of what I am talking about let me know.

I use my multimeter leads or the leads that come with my capacitance meter
Bit better quality then the cheapies supplied

So yeah best advice buy some good quality leads or plugs
(sockets and probes for that matter if you don't think they are up to it).

I suppose the big question then becomes were do you get decent quality connectors these days?

If you don't mind, Post some pics of the mod if you go with that
Thanks

Cheers

Per keep us posted mate

[Spacedye69]

Re: EVB ESR Meter (Bob Parker Design)

I will agree about the probes. The jacks seem to be pretty good, but the tension on the banana plug is low and the do not make a stable conection. I have to hold real still and wait 5-10 sec for the reading to stabilize.

[gdement]

Re: EVB ESR Meter (Bob Parker Design)

Congratulation's mate

WOW you got a silkscreened overlay should have make construction much easier for you so I am glad especially since this was your first kit I think you said.

The silkscreened overlay was one of the changes for the Mk2 version. If I understand correctly, you got the Mk1 so that wouldn't have had the silkscreen.

====

Mine arrived a couple days ago and is now working. I spent a crazy amount of time trying to debug something that wasn't broken - the startup diagnostic just isn't as easy to use as the directions make it sound. I thought it was frozen at the "-" but it really wasn't. I also had problems with the meter turning off when I tried to zero it.

My current problem is the probes. I figured out that the meter is working fine when I put pieces of wire or resistors directly into the banana plugs, but the probes produce wildly unstable readings making the meter unusable.

I've decided to solder them directly to the board, but I'm trying to figure out how best to provide strain relief. I don't want the probes to get yanked off the PCB.

[Per Hansson]

Re: EVB ESR Meter (Bob Parker Design)

Got mine yesterday, will assemble it in the weekend and post pics, mine too had a silkscreen...

[starfury1]

Re: EVB ESR Meter (Bob Parker Design)

Congratulation's mate

WOW you got a silkscreened overlay should have make construction much easier for you so I am glad especially since this was your first kit I think you said.

Yours might well have been an early production run since it appears to be 1 or 2% resistors

The overlay on the PCB should help others who like me weren't lucky enough to get one.

Cheers Mate, may it serve you well and save you lots of time

[Spacedye69]

Re: EVB ESR Meter (Bob Parker Design)

I am now an owner of a WORKING ESR meter! WOOHOO!

I started by making sure all the parts were there, and they were. I checked the board for bad/ missing traces, bridges, etc. I then began to install components, starting with the resistors. I found it easier to keep track by installing values that had multiples, then worked my way down to singles. I did the same for transistors

When all the components were on the board, I just followed the testing procedures spelled out in the instructions. To my amazement, everything worked the first time!

Calibration with the supplied resistors and instructions was fairly straight forward. This was the first device I have assembled from a kit, so I was pleased overall.

[willawake]

Re: EVB ESR Meter (Bob Parker Design)

well i think they should offer both. bob should go into business himself for this product.

[starfury1]

Re: EVB ESR Meter (Bob Parker Design)

There is a pole running on Bob's web site about the possible demise of the Kit from DS

Apparently Dick Smith Electronics have stopped making ESR meter kits
(some are still in stock).
I need to know if people prefer a kit meter or a fully-built one,
to know how we're going to fill future demand for them.
Please take the time to vote in my little poll. Thanks!

(scroll down a bit if you don't see it)

So please go "Vote your preference on this matter Bob's site Here

I don't know of anything cheaper then the Kit for a Digital one
but could be wrong too.

For those who don't have a Variable DC supply
Here's Bob's page on how to do it


Cheers all

[starfury1]

Re: EVB ESR Meter (Bob Parker Design)

Further to willawakes.... question here the info from the manual.

Please also note:
The typical ESR values are different on each meter for value of capacitance, reflecting improve technology in making them from the blurb on the MKII manual.

So Testing and Calibration....this is much the same (if not exactly) for the MKII version.

For Calibrating, Battery low a DC PSU Variable would be ideal but if you haven't got one there are ways to do it without have to buy one.

Cheers all

[starfury1]

Re: EVB ESR Meter (Bob Parker Design)

Hi Willawake, All

It came with 2 resistors
(1% think they are suppose to be)
5R6 and 82R
You adjust VR2 from memory
(Bit of a procedure to it)

BTW the above method of placing components leads is NOT the Accepted correct method

They should be flush (flat) to the PCB pad and yeah there would be technical reasons as to why.

Since I am the only idiot ever going to fix this and its mine I did it that way for 2 reasons.

Easier and less chance of PCB damaged if I have to remove a component.
Less chance of solder bridges.

Thats my excuse

cheers

[willawake]

Re: EVB ESR Meter (Bob Parker Design)

how did you calibrate it?

[starfury1]

Re: EVB ESR Meter (Bob Parker Design)

Hi all ok

Finished building the ESR Meter MKI EA Version So here are a few photos of the construction.

If you are building the Silicon Chip MKII Version see the photos of in my post way above.

Yes I made a few Boo Boo's so make sure you check your work...

It all working fine now

I highly recommend you have a Mag glass and or Jewelers loupe

First off I checked I had everything

DS forgot 1 resistor....(good thing I had one)

Then gave the PCB a good going over to make sure of no dags or broken tracks.

if you are not sure of a resistors value measure them

I next mounted Resistors (id start with the 1% ones) Diodes Sockets Transistors/Reg Capacitors LED's
IC's are left till last and thats after testing for +5V DC on correct pins of sockets.

These can be damaged by static so so take usual precautions with CMOS.

Check you work as you go along,
it really is very easy to make a mistake or create a solder bridge.
(why I scanned the PCB above, for reference)

A photo of both version is below too.

As the CMOS Cook Book says ...

Blame Your Self First and the IC's Last!

Good luck


Bob Parker's Design

Electronics Australia Version
ESR\Low Ohms Meter MKI

[starfury1]

Re: EVB ESR Meter (Bob Parker Design)

Thanks Guys for the update

BTW with the MKII I build I had to put the 220 uF cap on the back of the PCB
Next To the two 1N4004's
Pads were there but no holes in the pcb I got.

Haven't started construction of MKI yet but will soon

Cheers

[Per Hansson]

Re: EVB ESR Meter (Bob Parker Design)

Think Per was the other person that said he ordered one...
let us know how you go too Per.

Cheers

It was shipped the 6:th

So it'll probably be arriving any day now...