SF401 Plus 27Mhz-3000Mhz Radio Portable Frequency Counter Meter with CTCCSS DCS Decoder

Increíble, exelente calidad

Does what I needed it to do and more right out of the box. We have old radios at work and I needed a new antenna for one. Didn't know if the radios were UHF or VHF. This showed up with enough charge to tell me the frequencies of every channel. Checked multiple radios and got the exact same frequencies on all of them. It was very simple and intuitive to use.

Not bad for on air frequency recognition I use it for my Walkie Talkie reference frequency’s also picks up my WiFi 2.5bands

This is a cheap frequency counter and it works well for what it is, just don't expect it to rival a $500 machine. It picks up everything, I tried it with my FRS radio to map it to use paired with a GMRS radio. It worked great, then I tried on a second radio and it was all over the place. That was until I realized my phone was next to it. Moved my phone away and it was back to working great. You have to be careful and aware of what it around it. Also for picking up tones, you have to hold the TX button for a moment to get the tones. It picks up frequency really quick, tones take another few seconds to read.

My unit works and properly reports the TX frequency and CTCSS tone, if sending, as indicated in the manual. Attenuation was off and you really need to get the supplied antenna next to the TX antenna to get a reading. Please review my notes below carefully. DMR was the only mode to provide a frequency reading when the meter was set to digital. P25 and C4FM (Yaesu Fusion) could be identified only when set to analog.I tested the following all with correct frequency results:- 10 meter band using analog FM- 6 meter band using analog FM- 2 meter band using analog FM/P25/C4FM- 70 cm band using analog FM/P25/C4FM- 33 cm band using analog FM- 70 cm band using digital DMRI am pleased with the function of this meter and that it charges via USB as well. Still, if your unit appears to not be working after it powers up, you probably do not have the antenna literally next to or touching the TX antenna. I also tested by adjusting the "RF detect level" in the settings and moving it from 5 to 40. It did not appear to make a difference on the close proximity needed of the TX antenna to the meter antenna.

Buen equipo, me gustaria un poco mas de sensibilidad en la deteccion de frecuncia. Como en la mayoria de los equipos chinos el manual ess pobre.

So I bought this unit to test frequencies, though after reading a few reviews I found many others had to hold the antenna near or on the device emitting the signal. That said, it makes sense. Otherwise it will pick up any noise/frequencies in the air and will not be accurate to what you're trying to measure, this still the case when I held my test unit to the counter. It works well, though it could be better. However, I found going direct by feeding the signal directly into the input of the counter with an appropriate cable to both units, the counter measured far more accurately and consistently. That and it no longer picked up any surrounding noise in the air. Recommended not testing in the house with WiFi, cell phones, or any other device that transmits so it doesn't skew your results. Also connect directly using the right connection is by far the best way. Hope this helps. I'm sure someone with much more knowledge on frequencies and electronics would be able to fill in proper info and suggestions.

I purchased this to be a backup frequency counter for a portable inspection kit. It's easy to use and light weight. Thought it would be a great little unit. I tested it in the shop before putting it into the kit. It doesn't have enough accuracy to be useful. It MIGHT pick out a ball park range but the results but it's too crude to be of any real use.I test VHF radios in the 156.8 MHz range. I compared the counter to my old Radio Shack counter and they weren't even close. The new unit measured 158.316 MHz and my old one measured 156.8005 MHz (see pix). I plugged in a radio off the shelf that should be transmitting at 156.800 MHz (+/- .002) on channel 16.