







📶 Stay tuned, stay ahead — the SF401 Plus is your frequency frontier!
The SF401 Plus is a portable frequency counter meter designed for professionals needing precise measurement of continuous wave signals from 27MHz to 3000MHz. Featuring a temperature-compensated crystal oscillator (TCXO) with ±2 to ±4ppm accuracy, it decodes CTCSS/DCS tones and offers a rapid 0.2-second response time. Its lightweight 113g body, intuitive 4-button control, color LCD with dimming, and built-in rechargeable Li-ion battery make it an essential tool for field technicians and radio enthusiasts seeking reliable, on-the-go frequency analysis.
| ASIN | B01NA0957P |
| Batteries | 1 AA batteries required. |
| Best Sellers Rank | #114,952 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #9 in Frequency Counters |
| Brand | Surecom |
| Customer Reviews | 4.3 4.3 out of 5 stars (319) |
| Date First Available | February 6, 2017 |
| Is Discontinued By Manufacturer | No |
| Item Weight | 3.84 ounces |
| Item model number | 4350441046 |
| Manufacturer | Surecom |
| Manufacturer Part Number | 4350441046 |
| Package Dimensions | 7.72 x 6.61 x 1.93 inches |
| Special Features | Portable |
| Voltage | 1.5 Volts |
V**T
Works with digital & analog
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 DMR I 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.
J**.
Works well, just not easy to use.
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.
D**D
Great product
A great Cheap addition to my ham setup
J**R
You get what you pay for, and in that respect it works fairly well.
First unit was defective, seller replaced it with working unit in a day. It is an actual frequency counter that does read radio frequencies in the VHF-UHF range. It's claim to read 27MHz is false. Its sensitivity is low. You can increase it by substituting a better antenna. I used a BNC telescoping antenna from my other counter. The frequency counter is accurate, but not always on the first try. The CTCSS code reader is accurate. Unit needs about 3-4 seconds of unmodulated carrier before a frequency and PL tone will display. Tried it on VHF lo/hi and UHF lo/hi. Results were acceptable. A schematic diagram would be helpful. It needs higher gain.
D**L
Simple and effective
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.
C**K
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.
O**O
Works, read the review.
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.
K**Y
It works well
It works well but for me its accurate on expensive radios like it reads my Motorola XPR3300 accurate nothing wrong but when I switch over to my cheap Baofeng radios its off by like 5 so instead of reading 456.7689 it reads 456.7684 but its alright
A**D
Très pratique
S**T
C était pour un ami qui est très content
A**É
Il ne couvre pas les ondes du CB 40 canneaux.
A**R
Pour savoir le ctcss qui est très utile et facile a comprendre .
Trustpilot
2 weeks ago
2 weeks ago