Product Review: Multimeters

Tuesday, January 24, 2023

Product Review: the MPJA 35042 TE and ZOTEK ZT-5566SE Multimeters

The MPJA 35042 TE Multimeter

TLDR; This is an affordable and handy multimeter with good talking functionality. Added bonus of built-in transistor testing. 

This is a review and description of the MPJA 35042 TE Multimeter. It currently (As of 01/2023) retails for $39.95 from the MPJA website. (It needs a 9V battery which is not included.) It works well as a basic multimeter and also has transistor testing sockets built-in. The test leads that come with the multimeter are simple pin tips. It does not have automatic range finding. While the speaker volume cannot be adjusted, the device can be triggered to read the current value by briefly pressing the “TRUE/AVG” button. Also, it is unclear how to replace the fuse, should it blow. Overall, this is a great multimeter for anyone to own, and it reads values aloud clearly. 

Usage:

• When you first turn the dial away from the vertical OFF position, the voice announces “already on.” 

• When not measuring a value, the display reads “0L”

• To read the current value: briefly press the “TRUE/AVG” button. (second from left)

• If the value is outside of the range, the voice will announce “SUPER RANGE”

• To Turn OFF/ON Voice; Press and Hold (~3sec.) "TRUE/AVG" Button (second from left) Note: the voice automatically is set to ON any time the multimeter is turned on.

• To Read Frequency: Select 750 V AC Range (7th option, clockwise on dial) - Press ”HOLD/SELECT" (left button)

• To Turn on Backlight for brighter display: Press & Hold (~3sec.) "HOLD/SELECT" Button (left button) Backlight will turn off after ~10 seconds

• Multimeter is auto OFF: will turn off after ~20 min.

Description:

The multimeter is approximately 18 cm by 9 cm by 5 cm, and is teal with a black face.

On the top of the front side, it has a 4 cm by 6.5 cm screen display with two brightness settings (ON or OFF). 

Below the display screen on the left side, there are two rubber buttons. The leftmost button is the “HOLD/SELECT” settings button and the button to the right is the “TRUE/AVERAGE” announce value button.

Below the bottom right corner of the display screen is the transistor tester. It features 2 rows by 4 columns of pin holes. The top row is for NPN transistors, and the bottom row is for PNP transistors. The pin holes are labeled E, B, C, E. This mode can be accessed through the hFE setting on the dial (immediately right of the OFF position.)

At the very bottom of the multimeter are four sockets. From left to right they are 10A red, mA red, COM black, then the last one is “V, Ω, Hz,” diode symbol, capacitor symbol, red.  

Between the sockets are a yellow danger symbol, danger symbol, and electricity symbol. 

The 10A red socket is labeled as linked to the COM black socket by “10 sec MAX, 10A FUSED.” The red mA socket is labeled as linked to the COM black socket as “MAX 200Ma FUSED.” 

The red V Ω Hz socket is labeled as linked to the COM black socket as “MAX 1000V DC, 750V AC, CAT IV 600V” ground symbol.

The dial in the middle of the device is divided into 5 main sections (clockwise from the vertical off position they are VDC, VAC, ADC, AAC, ohms) with some individual settings separating the sections. There are 27 positions total, including the OFF position. The dial itself has a recessed circle to point to the current setting. When you first turn the dial away from the OFF position, the speaker announces “already on.” The different positions have detents and beep as you change between them. The dial can be turned clockwise or counterclockwise continuously.

The vertical position is labeled white “OFF”. To the right of “OFF” is the yellow “hFE” setting. 

Next is the white V DC (direct current voltage) section. Clockwise the settings read “200mV, 2V, 20V, 200V, 1000V”. 

The next section is yellow and is V AC (alternating current voltage.) Clockwise the settings continue “750 V Hz, 200V, 20V, 2 V.” 

The next section is white and is A DC (direct current amperage.) Clockwise the settings continue “20μA, 2mA, 20mA, 200mA, 10A.” 

The next section is yellow and is for A AC. (alternating current amperage) Clockwise the settings continue “10A, 200mA, 20mA.” 

The next section is white and labeled “NCV”(non-contact voltage.) 

The next section is yellow and is labeled with the continuity (diode and soundwave) symbol. 

The next section is white and is Ω resistance. Clockwise the settings continue “200Ω, 2kΩ, 20kΩ, 200kΩ, 2MΩ, 20MΩ.” 

The final setting (directly to the left of “OFF”) is 20mF. 

Overall, clockwise from “OFF” (vertical) the settings are as follows: hFE, 200mV, 2V, 20V, 200V, 1000V, 750 V Hz, 200V, 20V, 2 V, 20μA, 2mA, 20mA, 200mA, 10A, 10A, 200mA, 20mA, continuity/diode, 200Ω, 2kΩ, 20kΩ, 200kΩ, 2MΩ, 20MΩ, 20mF.”

The two test leads are identical and labeled “1000V CAT III 10A” double insulation symbol. They have simple pin tips 12 mm long. The cables are approximately 3’ long. The other end is a right-angle banana plug. The handle of the lead is 10 cm long, and the overall lead is just under 14 cm. The leads are 10 mm in diameter, with a 15 mm diameter flange to stop the user from contacting the tip of the lead.

On the back side of the multimeter, at the center top, there is a 12 mm wide opening to hang the device off of a screw or nail. To either side of the opening are slots for the test leads. (The wide flange on the lead has a horizontal slot for it, about ⅔ of the way down the vertical slot.) Lower down is a flap that can serve as a prop stand to stand the device up vertically. Underneath that flap is a warning “WARNING TO AVOID ELECTRICAL SHOCK REMOVE TEST LEADS BEFORE REPLACING BATTER OR OPENING CASE” Below that are the symbols for danger, double insulation, and WEEE. Below those symbols is the serial number of the device. Then below that is the Philips-head screw (which can be removed to access the 9V battery, and part of the PCB labeled RCAL 20.) The 9V battery has its terminals at the top with the positive terminal on the left side.

The ZOTEK ZT-5566 SE Desktop Multimeter 

TLDR; Skip this purchase. We couldn't get any of the talking functions to work; even so, many functions wouldn't talk even if they were working according to plan; the BT app isn't very accessible with VO: It can read the measured value in English, but it speaks in Mandarin for many of the other functions.

(As of 01/2023) The ZOTEK ZT-5566 retails for $94 on amazon.

 It is auto-ranging and also features Bluetooth speakers and displays the ambient temperature and time. It has a basic companion app (BluetoothDMM) that will display the values of the multimeter on your phone over bluetooth. It comes with a relatively comprehensive printed manual, rechargeable batteries, a charging cord (USB to USB mini-b,) and two test leads. 

The device is supposed to be able to read measurements out loud. We were unable to make this feature work successfully. It appears that there is no other way to trigger the value reading announcement other than by pressing the button on the test lead, and since the button on our lead appeared to be non-functional, it couldn’t read any of the values audibly. (The lead did correctly measure values, however.) 

Others have had more success with getting it to read the value out loud (note youtube videos) however it should be noted that even when functioning, the device won’t read anything aloud besides the measured values. (So it will not read the time, temperature, volume/range settings, battery level, etc.) It will also not read the frequency when measuring AC voltage, and won’t read the duty cycle percentage when measuring the frequency, even though those values are displayed on screen. It will also not read values when using the diode/led mode. 

The fuse is replaceable (but requires significant disassembly.)

Overall, this model is probably not worth the money, unless you aren’t reliant on the speaker for all your measured values, and really want bluetooth speakers combined with your multimeter to listen to music.

Usage:

• Don’t forget that any time you replace the batteries, the multimeter will need to be plugged in to charge in order for it to turn on. 

• When you press the buttons along the top, it will beep.

• Supposedly, to read the current value aloud: briefly press the button on the black test lead. 

• To switch from DC to AC, or from continuity mode to diode, press the given button twice. 

• Frequency and duty cycle % appear on the right side of the display.

• When not measuring a resistance value, the display reads “0L”

• The device does not beep if the vol/range is pressed. You use this button to change the function of the dial (between speaker and measurement range) but note that the only evidence of doing so is displayed on the screen on the dial (no beep, or announcement to indicate what mode the dial is in)

• The clock time can be changed by pressing the mode button on the back of the device, with up and down arrows. (again, display screen visuals only)

• The display brightness can be adjusted with the up and down arrows on the back of the device.

• The app displays the values from the multimeter on your phone, as well as a graph of the value over time, which can be saved, or you can share the entire display over text, email, etc. There are buttons on the app to control “AUTO”, “°C/°F”, capacitance, diode/continuity, NCV, Hz, ZERO, and AC A/mA. The graph and the dial showing the value can each be double tapped to enlarge the display.

Description:

The Desktop multimeter is approximately 20 cm by 13 cm by 11 cm, and has built-in speakers on the left and right sides. On the bottom side, it has 4 small rubber feet and two flaps that can be propped up to elevate and angle the device upwards if desired. (These are a bit difficult to deploy.)

On the front face of the multimeter there are buttons for all the measurement modes, ports for the test leads, a volume/range button, a display screen, and a dial for the volume and range that displays the time, temperature, battery charge, bluetooth status and mode that the dial is in. 

Along the top of the front face are 9 rubber buttons. From left to right they are “VAC Hz”,”mVAC Hz”, “Ω ohm”, capacitance symbol, continuity (diode and soundwave) symbol, “AC A  mA AC”, “HOLD”, “MAX/MIN”, and “REL.” Below this row of buttons, on the left labeled “DIGITAL MULTIMETER & BLUETOOTH SPEAKER” is a 11 by 4 cm display.

On the lower left side of the front face are 4 sockets/ports. From left to right they are red, black, red, red. The leftmost port is labeled “V, Ω, capacitance symbol, diode/continuity symbol, Hz”.  The port second from the left is black and labeled “COM.” The port second from the right is labeled “mA”, and the port on the far right is labeled “A.” The red mA socket is labeled as linked to the COM black socket as “MAX 200Ma FUSED.” with a danger symbol. The red A socket is labeled as linked to the COM black socket as “MAX 20A FUSED.” with a danger symbol. There is also a danger symbol between the leftmost red port and the COM black port. To the right of these ports is a red rubber button labeled “VOL/RANGE” 

There are two test leads, with approximately 100 cm of cable length, with simple 19 mm pin tips. The red lead is labeled “CAT II 1000V” CE, double insulation symbol, danger symbol, electricity symbol. The handle of the lead is 11 cm long, and the overall lead is just under 15 cm. The leads are 10 mm in diameter, with a 15 mm diameter flange to stop the user from contacting the tip of the lead. The other end of the red lead is a banana plug labeled “16A 1000V CATIII”, double insulation symbol, danger symbol. 

The black test lead is identical apart from having a tapering 13 mm diameter handle, 18mm diameter flange, and a small square rubber button located just above the flange. It does not have any labels or symbols on it. It also has a protective metal sleeve over the banana plug.

On the front of the multimeter, to the right of the rectangular display is a red dial, approximately 5 cm in diameter, with a display screen on it, below which is labeled clock/temp. Above the left side of the dial is a symbol of a person talking (there is no accompanying button). Below the dial on the left is a plus symbol followed by 5 dots around to the right side of the dial where there is a minus sign. Below this is the manufacturer label. 

On the rear of the device there are 4 screw holes in each of the corners (holding the body together) and 4 small protrusions so that the device could be stood on its back end if desired. 

There is a central panel labeled “WARNING TO AVOID ELECTRICAL SHOCK REMOVE TEST LEADS BEFORE BATTERY OR OPENING CASE” with a warning, double insulation, and WEEE symbol below.

Below that is a philips-head screw. If that screw and the panel are removed, two 2000 mAh lithium ion rechargable batteries (18650) are revealed. The further/upper battery terminal has the negative end on the left.

On the lower left of the back of the device (facing towards the back) is a larger rubber button followed by 4 smaller rubber buttons. From left to right they are labeled “POWER”, ”MODE”, up arrow, down arrow, and “°C/°F.”

On the lower right of the back face is a rubber flap/cap labeled DC5V 2A, covering the mini USB-b port. 

Above this port is a sticker with a QR code to download the companion bluetooth app. Below the code is the message “WARNING. 1. AVOID MEASURING HIGH VOLTAGE DURING CHARGING. 2. PLEASE UNPLUG THE CHARGING CABLE WHEN THE BATTERY IS FULLY CHARGED. 3. PLEASE COVER THE CHARGING CAP WHEN NOT CHARGING. 4. THIS CHARGING PORT IS NOT USED AS DATA TRANSMISSION. 5. AFTER INSTALLING THE BATTERY, YOU NEED TO CHARGE THE BATTERY TO ACTIVATE IT.” Below this is the serial number.