DROK Transistor Tester LCR Meter, Mosfet Transistor Capacitor Tester, Mega328 NPN PNP Transistor Diode Resistor Inductor Capacitance MOS SCR ESR Meter Automatic Checker Detector

The Drok tester is similar to many units, but is better built than most. The product includes a zero insertion force socket which may be plugged into the header socket holes protruding from the front of the unit. The fit of the ZIF could be firmer, and it probably would have been just as well to mount the ZIF to the circuit board and not bother with headers.The operation is pretty straight forward and the unit had no trouble identifying various types of thyristors, junction transistors, MOSFETs and diodes I tried. The only device which tripped up detection was a 50 Amp Schotty diode, which showed as “no component.” To be fair, that diode also eluded an expensive tester. I know the diode is good because it behaves properly under load.I believe this tester is a handy addition to have on the work bench as long as you keep your expectations realistic about what it can do.

Works fast. DOES NOT test unijunction transistors, silicon unilateral switches, or silicon controlled switches (old analog exotic devices). DOES test JFETs, SCRs, MOSFETs, BJT's and diodes.

I rated this item three stars as I found that it is handy and works pretty nice. I’ve tested several items thus far and found that it is accurate and easy to use. Three cons on this device worth knowing. (1) It eats up batteries fast, and these 9v batteries ain’t cheap. (2) The fast insert device is nice, and pretty much necessary, but falls out easily. Mine has become a floor dweller on more than one occasion, because it will not stay inserted in the device. (3) Price - I found the same device on TEMU.com for $12.00! This is a Chinese company, and it will take two weeks to get the item. But all these inexpensive test fixtures are coming from China. And for $12.00 I can wait the two weeks.

I would have given this 4 1/2 stars if I could. The only CON I have found is the mounting of the ZIF socket. It tends to be a little "wobbly" at times and requires care in inserting/removing components. Other than that one issue, this device is amazing for the price. As far as accuracy goes, it is certainly sufficient for "go/no go" testing of most electronic components. I tested several resistors, diodes, transistors, capacitors, and inductors. For all of the components I tested, the results were within similar ranges measured using other instruments on my workbench. This is a great little tool for pre-checking components before installing them. The biggest PRO I can name is the simple fact that you can place any component in almost any orientation in this device and it will automatically detect the type of component and report the proper measurement. For the price, this is a great little tool. The only other complaint I might have is the size of the screen; with my older eyes, reading glasses are a must when using this.

I acquired this after sending back another cheaper solution...twice. This one measures great so far - resistors, capacitors, diodes and transistors. Like other comments, the extra socket is a bit of an afterthought that tries to pop out when you push the lever down. For anything with two leads I've been using some jumpers that have mini-hooks on one end. One product suggestion: if they have anything to do with it, put the logo on the device label and put the website address in the manual. The startup delay is annoying and I don't really want to see it every time I power on.

I needed to match several transistors for hFe and the multimeter I had was giving me random readings so I purchased this dedicated transistor and couldn't be happier! Works very well and you don't have to worry about transistor orientation as it detects automatically. Readings are repeatable which is important.

There are a bunch of these Testers on Amazon. They started as kits, then some mfgs decided to build an enclosure to house the components for a more professional look.They seem to have 2 basic designs, this one and the other "thicker" unit with the "lead clamper" matrix built-in. I purchased both to see which one I liked better. This DROK Tester looked more "professional" with the "hand-held calculator" formfactor.However, when I actually used it, there were some serious issues. Obviously the ZIF (the aqua rectangle with the lever) was an afterthought. It fits in the socket, but the usual bumps on the underside of the ZIF (used to keep it above the PC board so solder can flow under it) keep it from seating properly. When moving the lever to clamp onto the leads of the component to be tested, the entire ZIF tips to the left. Unless you hold the ZIF in-place, the lever will unseat the pins on the right-side as it tilts to the left. Feels really wiggly, and very unprofessional. It could be glued in-place, but that seems like a ghetto work-around. The other option is to NOT use the ZIF and just put the leads directly into the socket. This would work, but it required forcing all leads into the socket holes simultaneously. For 2-lead components, this is fine, but for transistors or others with 3+ leads, this is much more time consuming. The ZIF allows the leads to be inserted "loose", and the lever does the clamping. Much more convenient! And that is why they added the ZIF to this Tester, even though it is an afterthought.It uses a 9-volt battery for power, not included. It displays the voltage of the battery on the screen. In fact it takes up the bottom 20% of the display, which is a bit of a waste. I would rather see more room for info about the component being tested than the onboard battery.Speaking of batteries, it eats batteries. I ran maybe 10 tests of different components. The battery started at 9.3v, and was drained to 9.0v. If a typical session requires the testing of 20 components, I would need to keep a spare battery around, or purchase pricey rechargeable 9v batteries. Conversely, the Aideepen Tester has a rechargeable battery on-board.The deal breaker for me was the display. Although I like how "clean" it looks, it doesn't display the data as well as the other Test unit. (Please refer to the screen shots.)On the left is the display from this DROK Tester. On the right is the competing Tester from Aideepen:https://smile.amazon.com/dp/B07RZRSBC5?ref=ppx_yo2ov_dt_b_product_details&th=1Both Testers are testing the same component, which is a simple transistor.The part I do NOT like about the DROK display is the pins are labeled as "123=EBC", which means I have to translate the pins to the EBC (Emitter, Base, Collector) pins of the transistor.A better way to display this information is to place the EBC next to the pins (1, 2 & 3) in the diagram. This is shown in the screen shot on the right. Much less mental gyration required to correlate the pins to the EBC of the transistor.If the DROK Tester were the only game in down, I would keep it, but I like the way the other Tester displays the information. Though it has a more "toy like" appearance, it is a good design ergonomically.Both are about the same price, around $30. Frankly, I would expect a Tester this sophisticated to be closer to $100. They are a bargain, considering trying to test components without one is an Easter Egg Hunt. Knowing a component's true values (vs. the published ones) is so much easier! :-D