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Reviews For: MFJ-224 2-Meter FM Analyzer

Category: Tools & Test Equipment for the amateur radio work bench

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Review Summary For : MFJ-224 2-Meter FM Analyzer
Reviews: 4MSRP: 180.00
MFJs revolutionary handheld MFJ-224 2 Meter FM Signal Analyzer lets you measure signal strength with over 60dB dynamic range and measure actual feedline loss in dB.
Plug in any scope and your MFJ-224 FM Signal Analyzer becomes a service monitor! Lets you visually analyze modulation wave forms, audio distortion, noise and instantaneous peak deviation.
Tune in any signal between 143.5 - 148.5 MHz. Built-in discriminator-meter function makes accurate tuning simple and easy. You can plug in headphones to help you tune in and identify signals easily. Theres also a battery check function.
Here are some countless jobs that your MFJ-224 FM Signal Analyzer can perform.....
Plot field strength patterns, Position antennas, Measure preamp gain, Detect feedline faults, Track down hidden transmitters, tune transmitters and filters, Check and set deviation anywhere in the band plus much more!
You can use your MFJ-224 FM Signal Analyzer to analyze audio quality with an oscilloscope, Solve FM radio problems fast, Scan the band, Tune in and identify signals, Tune transmitter and filters.
Product is in production
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# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
K3JLS Rating: 2016-03-18
Another MFJ Disappointment Time Owned: 0 to 3 months.
I bought this unit primarily to measure deviation on the 2 meter band as I like to refurbish the older 2 Meter FM radios. In this regard, it failed miserably. For example, I was unable to measure the CTCSS deviation using my scope and the unit's meter did not properly record the 1Khz tone either (it was under-reported from what MFJ claims is the more accurate scope display). I replaced the battery with a fresh one and this didn't help. I even tried to re-align the unit and could not find Test Point 1 (quadrature coil) on either the circuit board or in the schematic.
K4HYJ Rating: 2015-10-31
Seems to work good Time Owned: 0 to 3 months.
Purchased from a friend who has used it in his business. I've used it to measure F/B ratio of a yagi, and deviation on a TNC/VHF radio setup. The F/B ratio was basically the same as was advertised from the antenna manufacturer. The TNC deviation I will say was correctly measured - at least to the point of 100% connection success to a VHF Winlink gateway in the next county where I was only getting about 80% before. I was over deviating quite a bit according to the meter. The oscilloscope output is a nice edition, but I do not have the right cable to hook it up. The headphone output is a nice touch also so you can hear what you are monitoring to be sure.

I used it for a couple of hours at one sitting and the 9 volt Procell Duracell was still reading well into the green section on the meter (the unit also has a battery tester for its battery).

A lighted meter would be helpful for my aging eyes but that's not a fault of the instrument - I may add an LED later. There is plenty of room in the case around the meter which has clear edges. It would be easy to add an external power connection also (a good idea since I might forget and leave the battery inside).
VA6AWR Rating: 2012-05-25
Extremely Poor Performance - Save Your Money Time Owned: more than 12 months.
I've owned the MFJ-224 for approximatley 18 months.

Out of the box the analyzer would not stay on frequency for more than 30 seconds. It drifts so badly that it's little more than a novelty.

MFJ could have included a PLL circuit to address the problem, since the Motorola FM chip incorporates that feature.

MFJ is well aware that the analyzer's VFO is unstable. The instructions that come with the unit describe the process of aligning the analyzer but even after carefully going through this procedure the analyzer will not stay on frequency long enough to make a single measurement.

When I contacted MFJ for assistance, they offered to send me the schematic if I gave them my address. I gave them my address and they stopped communicating with me and now won't acknowledge any correspondence - 3 service requests submitted via their website and one fax.

I've contacted MFJ 4 times now over a period of six weeks but they've ignored all of my requests
except the first one. Not even an acknowledgement that they're working on the problem.

The MFJ-224 does not perform as advertised; not even close. Save your money!

WA4SCA Rating: 2009-09-26
Useful device, MFJ "quality" Time Owned: more than 12 months.
Functions very well, once you do the usual fixes needed with most MFJ products. As I use this primarily to set deviation, I calibrated it using the method of Bessel function nulls/zeroes. The MFJ-224 reads about 25% high, both using the meter or the 'scope output. So the actual deviation is about 80% of indicated.

When I opened the unit to install the battery, the "press to fit" nut on one of the 8 bolts dropped out of the sheet metal. This was fixed with a small drop of glue. Whoever assembled it could not possibly have missed the problem.

Once calibrated, and with a few minutes to allow stabilization, the unit works well, with accuracy comparable to a professional quality analyzer.