{"id":857,"date":"2019-03-16T20:03:08","date_gmt":"2019-03-17T00:03:08","guid":{"rendered":"http:\/\/realoldiesradio.com\/?p=857"},"modified":"2019-03-16T20:18:32","modified_gmt":"2019-03-17T00:18:32","slug":"review-volt-amp-meter","status":"publish","type":"post","link":"https:\/\/realoldiesradio.com\/?p=857","title":{"rendered":"Review: Volt\/Amp Meter"},"content":{"rendered":"
\"Volt-Amp<\/a>

Volt-Amp Meter<\/p><\/div>\n

I was cruising a web site and found this little meter for the amazing price of only $4.20.\u00a0 Such a deal, I thought.\u00a0 But was it?\u00a0 Maybe, depending on your application.<\/p>\n

The meter reads 0-99 volts DC, and 0-10 amps DC and could be very handy if it was not for one small quirk.\u00a0\u00a0 The sample for amperage is taken from the Negative<\/strong> side of the meter.<\/p>\n

\"Vendor<\/a>

Vendor schematic of suggested hookup.<\/p><\/div>\n

This may, or may not be a problem in your application, however it does require you to think about wire size, especially when working with a DC device drawing 10 amperes, DC.\u00a0<\/p>\n

The meter also does not have a fast sample rate, so use on something like a Yaesu FT-857D in the single sideband or CW mode would not be too helpful.\u00a0<\/p>\n

The meter seems to have about 350 mS refresh, and to be honest I was awful tempted to use a diode in place of the yellow lead and direct DC to a capacitor to stabilize the reading.\u00a0 That would, however, cause some errors in the readings.\u00a0 But maybe .1 of an amp or volt is not concerning to you.<\/p>\n

The negative (ground) amperage measurement does rule it out for applications such as automotive, truck gear, etc.\u00a0 I imagine with some MacGyver<\/span>ing you could put it into a project box for a bench power supply, or just to monitor a power supply output.\u00a0 Another application could be a monitor on a solar or wind charging system, as long as 20mA doesn’t bother you when calculating losses.<\/p>\n

The seller<\/a> has these on sale at Aliexpress for only $1.88<\/span><\/span> each, and sometimes as cheap as $1.09.\u00a0 So maybe it’s not entirely a bad deal.\u00a0\u00a0 They also have a voltmeter only in the same package.<\/p>\n

\"Rear<\/a>

Rear view of meter<\/p><\/div>\n

\"Wire<\/a>

Wire Connection<\/p><\/div>\n

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Seller’s Specifications on product<\/strong><\/p>\n