I sometimes buy inexpensive test equipment, perform a quick review and then post the results on my w3afc.com web page. I do this for the benefit of the HAM Radio operators who want to repair their own equipment, but who are on a fixed income. I''ll post a full review with...
I sometimes buy inexpensive test equipment, perform a quick review and then post the results on my w3afc.com web page. I do this for the benefit of the HAM Radio operators who want to repair their own equipment, but who are on a fixed income. I''ll post a full review with photos there in a couple weeks. This review is for the typical homeowner or DIY hobbyist who wants an inexpensive but full-featured meter. For comparison, I tested this meter against a much more expensive Amprobe AM-570.
- The dual, plastic coated magnet on the back is very useful. I can stick it to the face of one of my vintage HAM radios while I''m doing some testing and it will stay there.
- It has a large, easy-to-read display.
- DC and AC RMS readings are well within the claimed specifications. Spot-on, in fact.
- Resistance, DC current, and Diode forward voltage readings are accurate. I haven''t tested the Duty Cycle or Temperature functions.
- The build quality is above average for a meter in this price point.
- According to AstroAI, this meter can read voltages as high as 1,000VDC (CAT II) and 750VAC, but they don''t emphasize that. I have yet to use it to measure the 900VDC plate voltage on one of my Swan 700CX tube transceivers, because I want to get some use out of the meter first before I risk blowing it up. Plus, I plan to use this primarily for testing circuits in cars, and solid-state HAM radios. I had a UEI 384 that claimed a max DC voltage rating of 1000 volts, but when I tested the Swan plate voltage (at rest, no modulation) the UEI blew up - literally. I found another one online for 20 bucks used, and tried it again. THAT meter also blew up. So I tend to take the voltage ratings on these cheap meters with several grains of salt.
- The manufacturer claims that this meter will read capacitance up to 600 micro-farads (uF). But the one I''m testing has measured up to 2200uF with good accuracy. Perhaps they meant 600uF within the stated accuracy.
NOTE: I''VE CORRECTED MY RATING based on the fact that this meter is rated at 60,000 uF. The largest value I have right now if 20,000, and this meter reads it with the same approximate accuracy as my much more expensive Amprobe AM-570, and my CEM DT-9935 LCR.
- That magnet that I mentioned above can pick up nuts, staples, pins, and other stuff, so it''s a bit of a double-edge sword.
- The claimed frequency counter upper limit of 60MHz is actually 16MHz. Apparently, when engineering told marketing that it would read to 16MHz, marketing thought they said 60. And, the voltage required to obtain a reading is fairly high, almost 5V P-P. The Amprobe AM-570 on the other hand reads accurately up to 43MHz, and it only needs a little over 1V P-P for a good reading. Of course, it costs about $110, or almost 4 times as much as this AstroAI WH5000A. Note: I just checked my Amprobe manual, and it claims to read to 60 MHz also. I have a feeling that this is just a theoretical figure, based on the fact that these are 6000-count (5999, really) meters.
- The transistor hFE (current gain) test function is at only 1 volts, and at a very low current of around 1mA, so it reads about half of the gain of a device under typical conditions. And for some reason, the multi-function test adapter is arranged C-B-E instead of B-C-E, making testing TO-220 devices a hassle. So, DON''T buy this as a transistor tester.
As I said, I''ll post a complete review on my web page eventually. For a hobbyist, or DIY''er, this is good, and the price can''t be beat. For HAM Radio work I would spend a little more. BTW, I don''t find the beeping to be THAT annoying.
NOTE: The DC voltages were supplied by a Tektronix Calibration Fixture. The AC voltage was from a regulated AC supply, set at 115.00 VAC. I tested the AC separately instead of alongside the Amprobe meter because the AC supply doesn''t have BNC connectors like my Tek DC supply. With the probes detached, the AstroAI picked up a small amount of AC, most likely from my fluorescent lighting.
NOTE 2: In the photo of the meter testing something on the underside of a radio, the meter is measuring the frequency 14.175MHz from the signal unit of a Kenwood TS-930S HAM transceiver. The meter is connected to the board near the output terminal. It reads the signal, but the gain from the board (carrier level) has to be set at 10 to obtain a reading. By comparison, the Amprobe can read the signal at a carrier level of 4, and a very old Beckman Industrial DM27XT can get a reading with the carrier control set at 2.
In the two new photos of the meters measuring the value of a capacitor, the AstroAI and the Amprobe are measuring the same 2200uF, 35V electrolytic capacitor.
The manufacturer contacted me regarding my 3-star rating. Compared to other meters in the $30-$50 range, this would be 4 stars, perhaps even 5. However, I would only give the Amprobe AM-570 4 stars, so for the sake of consistency, I give this 3 stars.
By the way, I have the thermocouple connected right now, measuring the ambient temperature right here in my HAM shack. It''s fluctuating between 71 and 73 degrees as the heat cycles on and off, which is about right. I put the end under my tongue for a few minutes, and it leveled off at 95F. So it''s not lab grade, but it''s not bad.