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Reviews Categories | Antennas: HF Mobile & Accessories | MFJ 1668 mobile/portable screwdriver antenna Help


Reviews Summary for MFJ 1668 mobile/portable screwdriver antenna
Reviews: 5 Average rating: 4.0/5 MSRP: $159.00
Description: A 36 inch adjustment mechanism/coil with 2 telescoping whips, one 10 feet long, the other about 4 feet for mobile use while in motion.
Product is in production.
More info: http://www.mjfenterprises.com
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You can write your own review of the MFJ 1668 mobile/portable screwdriver antenna.

AK0O Rating: 4/5 Dec 31, 2011 16:40 Send this review to a friend
Decent and works  Time owned: 6 to 12 months
I have this mounted (using a BREEDLOVE) to the top center of my car. I do not drive around with it on.. I use a AT-271 (PRC-25-PRC77) whip on top. I have two markings on the antenna 3920kHz and 14292kHz I use this antenna to check into the daily emergency nets. Those of you who monitored the Pacific Net between August 11 and Dec 11 heard me on the MFJ 1668 when reporting in from State Eoc. Ain't a perfect antenna but it does work. The guys in the office at work are surprised what the hear when they are monitoring me. Although I am upgrading to a HI-Q, I will keep this antenna at work for ECOMMS.
 
WA4JM Rating: 1/5 May 21, 2007 11:40 Send this review to a friend
A Design Waiting To Fail  Time owned: more than 12 months
Hello All,

I've owned a 1668 for over a year now. I purchased mine new from AES in Orlando for $160. When I first received it I was very pleased with the constuction and easy tune-up. However as time passed problems with connections and high SWR began to crop up.

Here is the communications I've had with MFJ concerning this problem:

To: techinfo@mfjenterprises.com
Sent: Tuesday, March 20, 2007 12:12 PM
Subject: MFJ 1668 Connection Coil Contact Problems

Good Afternoon,

I have a model 1668 mobile antenna and over the past few months the connection between the copper finger stock and the coil windings has become poorer and poorer making tuning and operation very difficult. Iíve tried sliding the sleeve up and down several times in an effort to burnish the connection with no success. If I do manage to hit that lucky spot where I get a nice match it isnít long before itís gone again. This is so problematic that I have to fool with the antenna on a daily basis. Do you have any suggestions on how I can resolve this problem short of disassembling the antenna?

Thanks in advance, John

MFJ Reply:
is the antenna under warranty?
really, i guess you need to disassemble it and clean the areas, could be dust or other particles in there causing the problem.

My recent reply:
To: 'Richard Stubbs'
Sent: Monday, May 21, 2007 9:12 AM
Subject: RE: MFJ 1668 Connection Coil Contact Problems
Hi Richard,
I did what you suggested as the antenna is now unusable. I will send pictures to follow soon. The copper fingers at the top and the contacts at the bottom of the coil were covered with corrosion as a product of copper coming in contact with aluminum, The ďtubeĒ that slides up and down is white inside with aluminum crud. The round copper finger stock is covered with white crud where it comes in contact with the inner part of the tube. About the only things thatís not corroded is the coil itself.

I did a little research and found that copper and aluminum are on opposite ends of the reactivity scale. Let the two get wet with rain, run some current through the dissimilar metals and you have a recipe for failure. At this point, Iím not sure if the antenna is salvageable without replacing the outer tube and finger stock. The lock down bold is showing signs of rust.

FYI, this antenna has been mounted on a vehicle for over a year and the connectivity problems have gotten worse over time. It is not subjected to anything but rain. Possibly some of this might have been mitigated by placing a plastic sleeve over the coil as a rain storm detunes the antenna significantly.

John

MFJ Reply:

we can support you with additional parts. call 1-800-647-8324 to get part numbers and prices.

I guess I was a little surprised at the above response. Why would I buy replacement parts for a faulty design and do it say, every year? So much for the "legendary support." My guess is that I'm not the only one with these problems.

73, John
 
KC8NTP Rating: 5/5 May 14, 2007 07:03 Send this review to a friend
unbelievable  Time owned: 0 to 3 months
It took me a while to get the antenna, as it was back-ordered 6 weeks; the wait was well worth it. I hooked everything up when I got out of the dentist office one afternoon - I was not in a very good mood. I set it up right in the parking lot.

I tuned the antenna to 40m, which the SWR was through the roof. I used a cordless drill to put a sheet metal screw in the box of my truck (I have the antenna mounted in the box), I hooked up the little inductor that come with the antenna to the screw and the wing nut at the base of the antenna and opened up the windings a little, and bam, I got an SWR of 1.1:1 on 7.195MHZ.

This was around 16:00 local time and I made many contacts around the western states - including another mobile; I was also told that I had a signal that was 1S unit stronger than the other mobile who was running 500w, while I was running barefoot.

The only problem that I have found is that I must use an inductor on all bands, but that is easy enough. I have to use .3uH on 20m-10m. I think that this a product of having the antenna mounted in the bed of my truck; I have used a 102" whip on 10m, which I use the antenna at full length and still have to use .3uH to get it to tune.

I have since mounted the MFJ-1668 with a 102" whip on top and a cap-hat at the base - just above the coil - and on 75m I have gotten S9+20db reports all over the west and have made many contacts back into the eastern states with it (all barefoot). So to say that I am impressed is an understatement.

For the price, you cannot find an antenna that even comes close. I would also say, that in the configuration that I am using, it will smoke some of the other screwdrivers that I have used (that cost me 3X as much), and the little mono-bander whips can't hold a candle to it. the MFJ-1668 may be able to only handle 200w, but that is it's one and only handicap.

What I have wrote above is the only justification that I need for giving it a rating of 5.

John, KC8NTP, east central Nevada
 
N5EAT Rating: 5/5 Sep 27, 2005 16:53 Send this review to a friend
Problem with construction  Time owned: months
The receptacle assembly consisting of a bolt comming up and out from the top of the main antenna shaft and the 3/8-24 nut on the top which holds the bolt in place - and into which you screw your stingers - just fell off. The outside nut and washer apparently falling into the yard, the inner screw falling into the bowels of the antenna. I took out the bottom assembly and was able to retrieve the bolt. However, there is no way to take the top pvc cap off to re-assemble the top stinger hardware.

I called MFJ and explained the situation. This was Friday september 23. On Monday sept 26 my new antenna arrived. MFJ will credit my account when the broken unit arrives in Starkville.

I'm not going to lower my evaluation of the antenna as it's still the best portable system I have in terms of sheer radiation power, and MFJ's willingness to ship a replacement quickly. The individual pieces of this antenna, especially the coil and base, are of high quality. What I experienced was an assembly problem.

If you buy one of these - please make sure all the nuts and bolts are tightened down, and put some kind of adhesive on the tighten down points.

The only other problem I can see with this system is that i'm sure water will get into the coil-contact assembly when it rains. Most of the automatic screwdriver antennas you get (including my Little Tarheel II) has a moisture barrier around the coil assembly.
 
N5EAT Rating: 5/5 Sep 21, 2005 20:50 Send this review to a friend
Good  Time owned: 0 to 3 months
I ordered this antenna on saturday, received it today (09/21/05). It was fairly well packaged and came with 2 telescoping whips and an inductance coil to be placed between the antenna and ground.

I screwed the antenna with 10 foot whip onto my tri-mag mount and was astounded at the signals from it versus a well-known portable dipole. Also the noise level was extremely low.

Tuning this semi-monster was so easy. I hooked my MFJ analyzer up and took an initial reading. Based upon that, I lowered the coil a bit and saw the meter drop to 1:1. Bandwidth on 40 meters was the whole band, also on 20 (and it spanned parts of 13 megs and 15 megs. It took about 30 seconds to tune and set the antenna once for 40 and once for 20.

This signals comming off this antenna were awsome. My first contact was with Ed W1GUE in New Hampshire. At least a thousand miles. He was 599 here, he had me at 569 or so but good copy. Signal fading not a problem.

I tuned up 40 to aproxx 7.190 and made an ssb contact(short, just sig report - wanted to see how well he heard me). I got the first callback.
Again, the antenna is quiet.

I think this could be the sleeper of all manual screwdriver type antennas. I'm going to replace my 10 foot extendable with a 9 foot CB whip (i think a 30 mile per hour wind could bend or break the huge collapsable).

If you're looking at a Buddipole or other of the well thought of antennas, please give this one it's due. For portable use from your driveway, or from a mountaintop, this "hoss" is going to get out. Again - tuning is SO easy and reliable.

I'll refresh this review after a few months into are rainy season here in Alabama. But as of now, put this thing on your car, run some coax onto the house, and be amazed. You could take both the buddipole AND this screwdriver hiking with you and really be a formidable station using an antenna switch to choose the best antenna for each station.
 


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