Author Topic: Canadian Tire Mastercraft DMM New and old revision teardown  (Read 19412 times)

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Offline DIPLover

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Canadian Tire Mastercraft DMM New and old revision teardown
« on: January 26, 2015, 06:38:31 PM »
I agree with Dave that the sweet spot is to own 4 DMMs, so you can measure current and voltage in and out of your circuit all at the same time.

I believe you need one really good meter, and can get away with using cheap, serviceable meters for the other three.

My good meter is a Fluke 177 which is an absolute dream, and I get my cheap meters from a (large) canadian hardware store chain.

Canadian Tire has a full range of meters (6 or 7), from the $5 analog meter to the $50 and $60 manual and auto-ranging DMMs.

The top-end item is the $60 3 3/4 digits, 4000 counts auto-ranging model, which has OK specs :
DV Volts : 4V to 1000V ranges, 0.8% +5 counts
AC Volts : 4V to 1000V ranges, 0.8% + 8 counts
DC Current : 400uA to 10A ranges, 1.2% +5 counts
AC Current : 400uA to 10A ranges, 1.2% + 8 counts
Resistance : 400R to 40MR ranges, 0.8% +5 counts
Frequency : 4Hz to 400KHz, 0.2% +3 counts
Duty cycle : 0.1 - 99.9%, 1.2% + 2 counts
Temperature : -32-500 C, 1% + 6 counts
Capacitance : 40nF to 100uF ranges, 2% + 5 counts

It has 2 fuses (500mA and 10A) and a large backlight display.

I have compared measurements with the Fluke and with a 6.5digit Agilent benchtop meter and they have always been well within specs.

I think they are Decent meters for $60, but the real deal is they get heavily discounted (40-60%) about 3 times a year, so I bought mine for 30, 35 and 25(!) dollars in consecutive years.

They recently changed the model completely, while retaining the same product number (52-0052-2).

The specs and button layout are the same so at first I tought it was only cosmetic, but the new model uses 2xAAA batteries instead of the usual 9V, so I was intrigued enough to crack it open and see how much had changed (BEFORE I put batteries in and turned it on... >:D ).

Long story short : A LOT!.

I'll let the pictures speak for themselves. The PCB is much neater now, but the hardware (rotary wheel mainly) feels a bit cheaper. Also, the old model had a real removable holster while the new one is sleeker with a rubberized case and no holster.

I like that they now have small leds on top to indicate where to plug the red lead for a given setting.
What I don't like, is they now are rated for 20A with a disclaimer in a microscopic font that states that 20A should not be applied for more than 15 seconds in a given 30 minute period. That's BULLSHIT. Nothing in the meter's construction indicate it can withstand double the current from the older model. Shame on you marketing assholes, some dumb blocke is gonna get hurt because of this shit.

/rantover


 
« Last Edit: January 26, 2015, 06:41:47 PM by DIPLover »
 
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Offline retiredcaps

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #1 on: January 27, 2015, 06:44:32 AM »
Thanks for taking apart the meters and sharing the pics.  As a fellow Canadian, I'm interested in seeing the insides of the newer models.

The Mastercraft branded multimeters sold at Canadian Tire are made by Colluck.  See

http://www.colluck.com.hk/diyhp/9359/enus/l25520-0/Multimeters.html

The 52-0052-2 has undergone many iterations.  My friend has an even earlier version which uses two AAA batteries.

PS. The packaging for even the cheapest Mastercraft multimeter all have the UL symbol.
 
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Offline edpalmer42

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #2 on: January 27, 2015, 09:03:15 AM »
I bought this meter a few years ago at Canadian Tire for about $10 on sale.

http://www.canadiantire.ca/en/pdp/mastercraft-digital-multimeter-0520060p.html

For some reason I was using it with a large series resistor as a voltage divider, but the readings I was getting didn't make any sense.  I finally realized that the input resistance is only 1 Mohm instead of 10 Mohm!  Not a problem, just something to keep in mind!

Ed
 

Offline retiredcaps

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #3 on: January 27, 2015, 10:35:19 AM »
BTW, what is the part number of IC1 on the new version of the meter?  I can't quite make it out in the photos?
 

Offline DIPLover

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #4 on: January 27, 2015, 12:40:41 PM »
Just wanted to confirm I had paid $25 for the new version this past weekend.

And $10 with gas... I wish we had that deal here!
 

Offline BlueBill

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #5 on: January 27, 2015, 04:26:41 PM »
DIPLover, where did you get the Atlas ESR tester?
 

Offline poot36

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #6 on: January 27, 2015, 05:21:17 PM »
I have the old version of this meter (with 9V battery) that I have jumpered the 10A fuse with a screw and nut and can confirm that it will read upto 40A! (after that it displays ol (over load))  with the stock probes when testing a old 6 cell (2 parallel 3 series) li-ion laptop battery.  The only major problem that I have had is the capacitor tester function not working occasionally (have to wiggle and push down on the dial).  Another thing to watch out for is when the 9V battery gets down to around 3.5V to 3V the meter will start to act up.  The diode mode will only read up to 1V but will actually put out 1.3V or so so you cannot test LEDs (except maybe IR ones) with it.  It is also camping proof as well (great for checking fridge temp as well as deep cycle battery voltage and charging current solar or vehicle).  Also the temperature probe is liquid proof but watch out for the heat shrink on the end so that it does not come off (it may still be in our cars automatic transmission I don't know, I do know the car still works).
« Last Edit: January 27, 2015, 05:27:29 PM by poot36 »
 

Offline DIPLover

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #7 on: January 28, 2015, 07:36:15 AM »
DIPLover, where did you get the Atlas ESR tester?

I bought it last year from ABRA Electronics, a local shop in Montréal.
http://abra-electronics.com/peak.html?currency=CAN

Unfortunately, our money has morphed into Canadian Tire currency since then so the prices went up a bit.
I paid $155 at the time.
 

Offline BlueBill

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #8 on: January 28, 2015, 12:47:52 PM »
It's $174 CDn now, more than all your Mastercraft meters combined  ;)
 

Offline HammerJoe

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #9 on: April 09, 2015, 11:32:54 PM »
Is the new model a decent multimeter or should I stay away from it?
Its going to be on sale this weekend and I am thinking of getting one.
 

Offline retiredcaps

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #10 on: April 10, 2015, 09:31:33 AM »
Is the new model a decent multimeter or should I stay away from it?
Its going to be on sale this weekend and I am thinking of getting one.
I don't own this Canadian Tire(CT)  multimeter so I can't comment first hand, but based on the photos and some other factors, I would say it would be difficult to find something else in the $27 CDN + taxes ($59.99 CDN MSRP at 55% off discount).

Here are some comments on why $27 CDN + taxes could be a good deal for potential Canadian buyers.  Those not living in Canada will see a snapshot of the current environment.

On the plus side.

1) With the Canadian dollar at 79 cents on April 9, 2015 (compared to $1 USD), you will be paying more buying multimeters off ebay which is usually priced in USD dollars.

2) Buying a multimeter from ebay with free shipping from China takes 30 days or more to arrive and you may receive a bad/DOA one.  Who pays return shipping?  What happens if the multimeter is faulty after 30 days?  Is there warranty?  Remember free shipping from China to Canada does not mean Canada to China will be free or even economically feasible if the seller insists on a tracking number and signature.

3) Buying a bad/DOA multimeter from CT means going back to the store and getting a refund/replacement.  The multimeter according to the website states "This product carries a 1 year exchange warranty redeemable at any Canadian Tire store."  Check your local CT for terms and conditions as they may vary in different stores or provinces.

4)  As for the multimeter itself, there is a PTC, MOV and possibly a small power resistor for input protection on the volts/ohms input jack.  For the current jacks, there are two ceramic fuses.  It probably meets it CAT II rating, except for the fuses, given what I observed wrt to protection.

5) Compared to the older model, it looks like they reduced the number of components and calibration pots.  This could result in better reliability and long term accuracy and precision?

6) The leds are useful to remind newbies where to put in the probes.

7) For $27 CDN + tax, you get a lot of features like capacitance, temperature and frequency.

8] You are highly unlikely to find a name brand multimeter like Fluke, Agilent, etc for $30 used in working condition.  After 5 years of looking on kijiji, I have only seen 3 used Fluke multimeters sell for under $30 (Fluke 75, Fluke 23 and Fluke 12).

On the negative side.

1) The fonts are tiny due to bilingual requirements for Canada.

2) I think the older black on white text/lettering is easier to read than the newer white on black, but some would disagree.

3) The probes are likely to be crappy and highly unlike to survive 20A going through it without melting or catching fire?

4) The temperature functionality requires one probe in the uA/mA jack.

Note to NON Canadians.  There is very little choice in terms of brick and mortor/online for multimeters.  The big stores like Wal-Mart, Home Depot, etc carry multimeters but usually at full retail CDN price and rarely go on sale.  In addition, they are overpriced compared to the USA counterparts even when the CDN $ was at parity with the USD $.  For example, the cheap 830 sells for $15 CDN at Wal-Mart.  At Harbor Freight USA, you can usually get if free or on sale for $2.99 USD.

Buying multimeters from USA sellers (either ebay or online stores) yields more selection, but priority shipping + tracking number + signature can exceed $30 not including any customs taxes/fees.  In addition, FedEx and UPS may charge a "brokerage" fee of $35 or more for doing the customs clearance/paperwork.

Anything over $20 CDN via postal/courier is subject to customs fees/duties in Canada.  An excerpt.

https://www.canadapost.ca/tools/pg/manual/pgcustoms-e.asp#1382719

Customs duties and taxes
The CBSA collects provincial sales taxes (PST) on most taxable imports valued at over $20CDN entering Quebec, Manitoba, Saskatchewan and British Columbia. The CBSA also collects Harmonized Sales Taxes (HST) on most taxable imports entering Newfoundland and Labrador, Nova Scotia, Prince Edward Island, New Brunswick, and Ontario.

A handling fee of $9.95CDN per dutiable or taxable mail item is applied. This fee is in line with the government’s efforts to help recover costs from those who benefit from services, and is similar to arrangements in the United States and other countries.
« Last Edit: April 10, 2015, 10:33:30 AM by retiredcaps »
 

Offline Bud

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #11 on: April 13, 2015, 03:56:17 PM »
I have a Flike 87 V on my electronic bench but I was looking for a second lower grade multimeter for around the house work. Conveniently Canadian Tire put Mastercraft  052-0052-2 on sale this week so I went and bought one. Gosh, it was only CAD 25 sale price, which after tax is equivalent to about USD 23. As it turned out after my quick testing, it was a hell of a deal, even though it had its share of corners cut.

Overall build quality is very good for the price. Quality of plastic is OK to me. The halves of the casing are well molded, even though there were some minor blemished around the perimeter where they connect. The stand is somewhat flimsy though. It does the job but flexed too much on the bench as I was pushing buttons and operated the selector switch. I have a feeling it may break at some point.

This multimeter has curved casing and it is noticeably lighter then Fluke 87-V. It was much nicer feeling holding it in hand than 87-V. It is also a bit smaller. In terms of thickness it seems to be slightly bigger than 87-V. With the stand the tilt angle is smaller than 87-V and about 45 degrees, but in fact I liked it better, I never understood Fluke 87-V standing almost vertically on the bench. Also after checking the viewing angles it appears the tilt angle is actually optimal for the operator in sitting position and MC multimeter on the bench with the stand engaged. Pictures are attached below.

Backlight is pleasant with the LED color similar to Fluke 87-V. But turning backlight on/off is a bit akward because the same button activates Hold function. So you push the Hold/Backlight button for a sec and the backlight LED turns on but at the same time Hold function gets enabled, so you need to momentary press the same button again to disable Hold. Same thing when turning backlight off. Somewhat annoying.

The multimeter I got was a dual AAA battery model. Batteries were not included, so I opened the battery cover to install my own pair. Right off the batt I noticed a fuse which was not sitting properly in the holder. One of the holder contacts was sort of bent. Closer look revealed that apparently the fuse contacts soldered too close to each other (poor PCB footprint?) so the fuse could not be put in place so they had to bent one of the contacts. And it appears there not much  can be done to fix that. A picture is attached below.
Next I put the batteries in and had a feeling that the battery holder plastic is thin and may break if not careful when will be changing batteries. Quality of the battery holder could be better.
I tried to put the battery cover in place and found it does not fit anymore. It was because there was a square block of rubber foam glued to the back of the battery cover to push on the battery holder to hold it in place (it was already attached to the PCB using a sticky tape). But for whatever reason that piece of foam was too big and you cant close the cover with the batteries installed. A picture is attached below. To rectify this issue I removed half of the foam thickness with a knife and the cover closed.

The display is nice and big. I like it. Backlight is nice. The buzzer is soft and I at first liked it (to my taste buzzer on Fluke 87-V is too loud), but after I turned on my bench power supply and a signal gen, the buzzer sound was masked by their fan noise, so on the bench  the buzzer would probably be too weak. It should be OK when doing work around the house though.

The test leads are usable around teh house but the probes made from hard plastic and the tips are not sharp. Also because it is hard plastic, the lead wires may eventually break. The wires are OK though, they are as silky smooth  as the probe wires on my 87-V but rated 80 degrees C. I have a spare pair of Fluke test leads and I used them to test this multimeter.

I will post next some test results how the multimeter tracked my Fluke 87-V and my bench HP 3456A.

Pros:
- good accuracy in tested modes: DC voltage, DC mA/uA current, Resistance (AC not tested)
- nice backlight
- big display digits !!
- soft wires on probe leads
- very good value for the price
- feels good in hand
- fairly light

Cons:
- selector switch somewhat clunky
- backlight function is awkward, coupled with the Hold button
- while probes wires are nice, probes themselves could be better (plastic and tips)
- weak buzzer
- weak stand
- small print fonts and somewhat confusing location of button annotations
- battery fuse holder seems to be improperly soldered, so the fuse does not sit properly.

In general, I'd say it is a very good multimeter for the value (heck, only USD 23 for its good accuracy). So if you are in Canada see if you want to drop by your local Canadian Tire store and grab one while it is on sale.
 

Offline SeanB

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #12 on: April 14, 2015, 06:10:21 AM »
Panasonic branded batteries, those I see here are not exactly the best advert for Panasonic, seeing as they only last a month in a wall clock, and a week in the one with continuous sweep.

In a DMM they probably will last the usable life of the meter.......
 

Offline Bud

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #13 on: April 14, 2015, 11:17:48 AM »
That is right, not the best batteries, just had a spare pack of them handy, bought I think for a $1 for a pack of 4 at a dollar store for my LED flashlight. I will replace with a decent pair of batteries to avoid changing them for as long as possible, as I said the battery holder plastic is not of best quality so better not touch it.

Anyway, I've ran the meter against Fluke 87-V on DC volts and uA/mA. This Mastercraft multimeter agreed with 87-V  well, especially on DC volts. Pictures are attached below for measuring 1V DC and 1mA DC.

Other measurements :

- resistance was tested against Fluke 87-V and HP3456A

R      Mastercraft   Fluke     HP
=====================================
1 Ohm    0.9        1.0        1.04
10 Ohm   10.0       10.0       10.08
100K     100.3K     99.99K     99.94K
1M       1.046M     1.04M      1.038M


- Frequency was tested using a HP8656B synthesized signal generator as the source.

F       Mastercraft    Fluke
==============================
100kHz      99.98      100.00

Sensitivity,  1.3       0.09
V p-p


Mastercraft meter was off a bit but well within specification. However its sensitivity was 1.3V peak-to-peak which is OK for digital circuits but may be insufficient for analog stuff. Fluke in this regard was more than an order of magnitude better. As to me I never use multimeters to measure frequency, so this function is not important to me.

- Capacitance was tested using a 39pF ceramic disk capacitor, 1000pF polypropylene cap, and a 100uF aluminum electrolytic cap.

F       Mastercraft    Fluke
==============================
39pF      0.045 nF     0.04 nF
1.0 nF    1.128 nF     1.00 nF
100uF     101.1        97.8

Mastercraft's meter readings of capacitance seemed to be on high side vs Fluke, but I do not have another meter to reference the test capacitors.

The meter also has LEDs by V/A test sockets, indicating where you should connect the test leads depending on the selected measurement mode. This may be of a help to a beginner. I do not need it and it was more of a worry that the LEDs consume extra battery power.

Overall I am happy with the meter, it is pretty accurate except for may be some more demanding work on the bench, and it was bought as a grab and go tool for working around the house. And heck, hard to beat it for USD $23.
 

Offline HammerJoe

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #14 on: April 16, 2015, 01:55:41 AM »
Great reviews so far that seem to confirm that its a decent device and the sale was a great deal.

For those that got one can you please confirm something about the screen?

I got one and the screen when looked in a certain way has a yellowish tint on the top right of the screen, its like that are got alot of heat.

I thought it was a defect and it was bothering me (the numbers were fine) so I took it back and replaced it another and it has the same thing.
I checked it at the store and didnt see it.

This second one also when I use the backlit function it looks like a tiny bit of the screen is dirty for lack of a better word.
The numbers display fine so I guess I will just have to learn to ignore it. :)
 

Offline Bud

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #15 on: April 16, 2015, 01:21:54 PM »
I checked mine after 10min and could not see any tint on the screen.
 

Offline HammerJoe

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #16 on: April 17, 2015, 01:06:02 AM »
Here's two pics of the halo effect on mine. I had it replaced and this one has the same display so it's either normal or I'm just unlucky. :)
It's nothing major but it's one of these things that once you see it you can't unsee it.


And then the other one that's visible when the backlight is on where the V is displayed


 

Offline Bud

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #17 on: April 17, 2015, 03:49:18 AM »
Did you take the halo picture in daylight of electric light? You sure it is on the lcd and not on the internal side of acrylic cover?
 

Offline macboy

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #18 on: April 17, 2015, 07:31:16 AM »
Well, this is currently (to end of today) on sale for $25 CDN so I thought maybe I'd buy one. Then I thought, the last thing I need is another multimeter. So I bought one.

The physical build quality isn't so great. The input jacks are poorly made and are not on standard spacing, so things like BNC-banana adapters won't fit. This meter will never see mains voltage nor anything over 100 VDC on my bench, but it has its uses.

The specs on the package indicate 4000-count ranges: 4 V, 40 V, etc., but actually this is a 6000 count meter (6200 to be precise), so the ranges are 6 V, 60 V, etc. I guess they didn't update the specs when they updated the meter.

I quickly tested the 6V, 60 V, 600 uA, and 6 mA ranges, and all agree to within 2 counts (at full scale) with my Keithley 2001 7.5 digit meter(s). The math will show you that the overall error is less than 0.05%. This is very impressive for a device so cheap it is practically disposable. Capacitance readings are within a few % of my DE-5000 (tested a 470 uF and a 47 nF cap), not too bad. This was in a nice comfy 21 degC room; outside in the heat or cold, the accuracy may not be so good.

The frequency counter works all the way to 15 MHz (limit of my function generator) with just 800 mVRMS input. That is truly impressive; most multimeters will not measure that high. It displays up to 9999 count before up-ranging.

The AC volts measurement is - almost unbelievably - True RMS! And accurate! 1 VRMS measured at 1 VRMS. Amazing. Unfortunately, the frequency response starts to roll off rapidly after 1 kHz. This means that even True RMS readings need to be taken with a grain of salt since it isn't responding to anything remotely high frequency. But indeed, a 100 Hz, 1 VRMS triangle wave measures as exactly the same voltage (within 1 count) as a 100 Hz, 1 VRMS sine wave. Another cheap meter that I know is not true RMS showed about 980 mV.

I also picked up the K type thermocouple probe designed for this meter. It seems to be within a few degrees agreement to the Keithley 2001 using a type T thermocouple over 0 C to 350 C. The Keithley has sophisticated processing that linearizes the thermocouple readings to within a fraction of a degree.

The specification for the capacitance measurement tells us it goes up to 100 if, which is on part with a cheapy multimeter cap test. However, I can confirm that it measures up to 60000 uF. That is not a typo: sixty thousand microfarad. My trust B+K goes up to "only" 50000, and it takes much longer to return a reading at those high ranges. This one returns the first reading within around just 5 or 6 seconds.

I will update as I test more.
« Last Edit: April 19, 2015, 11:24:58 AM by macboy »
 

Offline Paul Moir

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #19 on: April 17, 2015, 08:26:34 AM »
Canadian Tire is a bit wise to cheap multimeters I think:  a couple years ago they recalled one of their meters.  Unfortunately this was a inexpensive little DC & AC clamp meter.  It looks like it was some fault in the voltage measurement range which did it in.  Wish they wouldn't even bother with those on clamp meters.  :(

Thanks for the heads up, I think I'll run out and grab one to replace my old (pre CAT) DMM which I managed to blow the current source out of.
 

Offline HammerJoe

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #20 on: April 17, 2015, 08:34:26 AM »
Did you take the halo picture in daylight of electric light? You sure it is on the lcd and not on the internal side of acrylic cover?

The first pic was taken in daylight and to see have to manouver the dmm just right to see it in full glory. The second picture its only visible with the backlight on.

And yes its on the LCD because the digits bars cover it so its underneath it.

No biggie, I just have to learn to ignore it.



Thank you Macboy for your tests. It seems that this is a good deal afterall for $25.00.
 

Offline retiredcaps

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #21 on: April 17, 2015, 09:10:41 AM »
BTW, what is the part number of IC1 on the new version of the meter?  I can't quite make it out in the photos?
I'm still curious what this IC1 is if someone takes theirs apart?
 

Offline Bud

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #22 on: April 17, 2015, 09:16:01 AM »
Thanks for the heads up, I think I'll run out and grab one
They also have (eev)blogger knife

http://m.canadiantire.ca/en/pdp/yukon-gear-x-large-bowie-knife-9-in-0753516p.html
 ;)
 

Offline Paul Moir

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #23 on: April 17, 2015, 09:28:54 AM »
BTW, what is the part number of IC1 on the new version of the meter?  I can't quite make it out in the photos?
I'm still curious what this IC1 is if someone takes theirs apart?

DTM0660L

Full markings:
H208
DTM0660L
R414K.B

Google says have a look at this:
http://www.eevblog.com/forum/testgear/new-trms-uni-t-ut139c-dmm-is-available-now/30/
Which says it's a Hycon HY12P65 http://www.hycontek.com/e-page2-HY12P.html
:D

J8 goes to the TST/EUART RC/Psomthign so maybe for calibration?  Gotta trace out the EUART TX...


Damn, forgot to pick up the knife too.  :) 
« Last Edit: April 17, 2015, 09:50:11 AM by Paul Moir »
 

Offline Paul Moir

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Re: Canadian Tire Mastercraft DMM New and old revision teardown
« Reply #24 on: April 17, 2015, 04:36:36 PM »
Hey, this thing is pretty awesome for a cheapy, and I should know, I've owned an awful lot of cheapies.  :)

The LEDs are awesome.  No one bats 1000 and I know the little "LEADS" display on my Fluke has saved my fuses a number of times.  If you don't have a probe in the correct socket, a little light next to the socket lights up.  If you have it in the wrong socket, it beeps at you.  Almost as good as that Gossen Metrawatt.  Oh how I wish this thing was rated more than CAT II:  it could be a great field meter.
The LEDs and alarm are activated by little switches that contact the shrouds.  Unfortunately the LED burns about 1.5ma, so it'll knock back battery life a bit if you're using unshrouded banana jacks.  I measured about 2.2 mA measuring / 3.7mA with LED.  Course backlight and beeper consume more and some ranges are different. 
Continuity and Diode measuring voltage checked as 3.2V, which is great for me because my Fluke 175 is a LV CMOS destroying 7.5v.
Backlight works I guess.  I still don't get why multimeters have them, but whatev.
Hold is the typical useless type.  It'll even hold a blank screen while autoranging for you!
Continuity is near perfect.  The Fluke can catch shorter transients but this one is pretty darn fast. 
Input impedance of this model appears to be 11Mohm - manual claims 10Mohm. 
Amps default to DC as God intended.
Update rate is pretty snappy; got to be 10Hz or maybe more?


Not so good:
The uA range has a 100 ohm shunt so I guess 100mV/mA?
No mV range.
No bargraph.  You don't get a bargraph for 24.99.  :)
EUART TX goes into IC2, which appears to be an amplifier for the beeper and LEDs.  No data on it I'm afraid.
J8 when jumpered puts the meter into CAL mode.
Case *almost* fits AA batteries.  Pretty obvious the mold was made to use a 9v battery. 

Can't say more about accuracy than what macboy said with his excellent equipment.  I get a bit of a mismatch on the TRMS with a square wave, but sine and triangle are very good.  Also I noticed when at lower voltages (~1v or less) the freqency will drop out if there's some DC offset + or -.  Seems fine at 2v.  No big deal though.
Meter beeps 2 beeps when started with the backlight switch down, and 5 beeps with the multifunction switch held down.  Haven't figured out the function yet though.
(EDIT holding the backlight switch at start *may* turn off the auto-backlight-off.)
« Last Edit: April 17, 2015, 04:58:34 PM by Paul Moir »
 


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