MFJ-1924 Screwdriver Antenna Controller

This review is way past due. I’ve had my MFJ-1924 screwdriver antenna controller for about three years. I bought it around the same time as my Scorpion Mobile HF Antenna. Later, I replaced it with an automated controller that measures SWR, memorizes antenna positions, and has a small remote control head. In the end, I felt that the tech in the automated unit was too temperamental in my particular mobile installation. It routinely failed to tune, had to be reset, or emitted annoying codes to indicate a problem. So, I reinstalled my MFJ-1924.

I suspect that plenty of screwdriver antenna owners are wondering, “Why do you use an antenna controller at all? Just listen for the noise peak!” Yes, the antenna can be positioned manually with the included rocker switch. Simply listen for the signal or band noise to peak, stop the antenna, and then fine tune with the transmitter. However, I appreciate the freedom of being able to press a button and focus on other things during antenna motion, whether it’s driving the car or perhaps setting up a log before I begin an operation. If I’m driving, sometimes it’s difficult to hear the noise increase as it nears its peak. My car is a bit louder than most since it’s modified for fun.

I want to make it clear that I’m not bashing automated controllers. I think mine is well-built and relatively easy to use after a moderate install and set up. It just didn’t suit ME. I’ll make a few comments about it below. I’m not fond of sellers who denigrate their competition in order to sell a product. Instead, my intention is to compare and contrast between the two products that I’ve owned and used.

With that said, here’s why I like the simplicity of my MFJ-1924 over more sophisticated antenna controllers: My Scorpion is mounted to a trailer hitch that’s relatively close to the ground. It’s not ideal, but it’s the best option on my small car. Being close to the ground, my SWR is affected by surroundings that may not matter with other mobile antenna mounting locations. Examples of elements that affect my tune include the steel rebar that’s within concrete roads or parking surfaces, roadside guard rails, wet roads, and even the traffic around me. As a result, the antenna positions stored by my automated controller were often inadequate unless I was in the same location as when I stored the antenna position. Initially, it used SWR to find a coil position with good SWR, which is good. But, once the position is stored, future tuning comes from memory rather than SWR tuning. The antenna frequently needed to be fine-tuned or retuned manually.

The MFJ-1924 also requires fine-tuning; so, what’s the big deal? My automated controller would frequently emit a fault code and stop working until it was reset. Its reset operation drives the Scorpion to the upper limit, then the lower limit, and then it’s ready for another attempt to tune after about two minutes. IF the tune was close, then I still had to press the soft-touch up or down button (shown here) to attempt fine-tuning. A flashing LED indicates that the antenna motor is turning, but no counter to indicate its direction of travel or how far it has moved.

The MFJ-1924 is very easy to program. Find a frequency in each band to store. I usually choose a frequency that’s in the center of my privileges on each band. Use the “UP” or “DOWN” button to adjust the antenna coil manually until there’s an SWR match, then press and hold the number for the memory location you want to use for that band or frequency. Once a position is stored, an easy press of the applicable button will prompt the controller to move the antenna coil to whatever position is stored. The operator has an immediate indication if something is not working (counter does not change). Once the antenna is positioned, the operator checks SWR with the transmitter and then fine-tunes… no fuss, no muss!

Operating the 1924 reveals what I think is its best point, particularly in a mobile setting: The large, old-school, clunky buttons are easy to see and easy to press without bumping anything else. There’s enough space between them to avoid accidental selections and the touch is very light. The numeric display counts up or down as the antenna moves. If you know where the antenna is supposed to stop, then it’s very easy to know if it’s “almost there” or if it has passed the position for some reason and needs to be stopped, which can be done without causing an error. Let’s face it, most screwdriver antennas miss a pulse count or two from time to time. Resetting the counter on the 1924 is very fast and easy. Simply press and hold the “UP” and “DOWN” buttons simultaneously for a few seconds. The antenna will drive to its lowest position and reset the counter to zero. It’s ready to go within 30 seconds, even sooner if the antenna was tuned to a higher frequency.

Speaking of the antenna’s lowest position, my automated controller does not operate the antenna at its lowest position. It finds the lowest position during a reset, then positions the antenna about three turns up from there, which makes it almost impossible to tune whatever frequency is at the antenna’s lowest position (10m for my whip and 15m for my caphat). I could alleviate that by shortening my whip or using a smaller caphat, but I’d rather just work the full range of the antenna. The MFJ-1924 will drive the antenna to the lowest position and stop without triggering an over-current fault.

Which screwdriver antenna controller do you prefer? If you don’t have a controller, is the MFJ-1924 something you might like to try? It’s less expensive than more sophisticated controllers; plus, it doesn’t require a connection to your radio’s CAT port. It moves the antenna only when I press a button. I may try an MFJ-104 someday, but I’m quite pleased with a simple tool that works well.



About Scott

I grew up near Houston, TX and served in the U. S. Coast Guard ordnance and electronics communities for over 35 years. I became involved with ham radio and computers in 1995. The explosion of technology made my jobs and hobbies quite interesting. My hobbies include Volkswagens, bicycling, photography/videography, electronics, ham radio, and web management.
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