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Author Topic: Opinions on MFJ 1699T Antenna  (Read 202 times)

N6NWW

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Opinions on MFJ 1699T Antenna
« on: March 10, 2022, 07:55:37 AM »

Hey There,
I’ve been using Lakeview Ham–Sticks with so/so luck, I can get good matches on the 80 and 40 meter sticks but struggle to get below 3/1 on the 20, 15 & 10 meter sticks. I have them mounted on a 3/8-24 mount which is mounted to a roof rack (steel) which is grounded via 1” braid to the frame of my Tacoma and the antenna mount is fed with RG8X.

So the question is; anyone have opinions, comments and experience with the MFJ 1699T multi band antenna? Seems like an inexpensive choice with some OK to good reviews found on line. I appreciate your honest input and how one worked for you who have tried one before I make a decision.

Thanks Erik N6NWW
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K5LXP

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Re: Opinions on MFJ 1699T Antenna
« Reply #1 on: March 10, 2022, 11:00:55 AM »

20M and up is moderately efficient for even a hamstick, so I don't think your solution lies with a different antenna.  My take on it would be to sweep the installation with an analyzer and see what the issue is.  Could be some strange resonance with your roof rack or common mode with the feedline.  A "braid" to the frame has a relatively long length and could be contributing to the problem.  Bonding to the body and then the body to the frame would be a better way to go.

Mark K5LXP
Albuquerque, NM 
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KH6AQ

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Re: Opinions on MFJ 1699T Antenna
« Reply #2 on: March 10, 2022, 02:29:43 PM »

The MFJ-1699T is 50" long whereas a Lakeview Hamstick is around 90 inches. Being shorter the 1699 will be less efficient.

How long is the ground strap from the roof rack to the Tacoma frame?

MFJ-1699   https://mfjenterprises.com/products/mfj-1699t
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N6NWW

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Re: Opinions on MFJ 1699T Antenna
« Reply #3 on: March 10, 2022, 05:45:47 PM »

Thanks for the replies. So let me give you some more information on my truck. It’s a 2001 Tacoma 4x4 extra cab 2 door, with a shell (fiberglass) and the roof rack is a home made steel ‘cargo carrier’ roughly 4 Ft. x 5 Ft. secured to the shell so I know it’s ‘floating’ above the truck body and ground plane. Yup, bad but I didn’t want to put holes in the truck itself. Also in the shell is my VHF/UHF antenna, NMO mounted through the shell centered about 5 inches behind the cab. Inside the shell I added a roughly 3 Ft. x 3Ft. metal ground plane which the NMO mount goes through and is also grounded to a chassis. That matches great, no issues.

OK back to the HF antenna, the 3/8-24 mount is in the left front corner of the rack with the bracket welded to the rack. Again, I know not optimum and not being in the center for a good ground plane. The ground braid is about 4 ½ Ft. long and goes from the front of the rack down to the frame between the shell/bed and cab. (Plenty of ground for the offroad lights up there). I do have and use an antenna analyzer and find the dips in a couple way out of band spots on the 20 meter Ham-stick, like 10MHz. In the 14 MHz area I can get close but never under 3/1.
 
I’m probably hoping for too much with the goofy setup I have. But trying out things is what this hobby is all about. I’m intrigued with the 1699 and not having to swap entire antennas, just the jumper so I though it would be worth a try.

Thanks Erik N6NWW
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K5LXP

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Re: Opinions on MFJ 1699T Antenna
« Reply #4 on: March 11, 2022, 09:32:48 AM »

Since the hamstick and the MFJ are fundamentally the same antenna (physically short coil loaded marconi) I wouldn't expect a vastly different result, i.e. if a hamstick doesn't work the MFJ won't either. 

Mark K5LXP
Albuquerque, NM
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KG4RUL

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Re: Opinions on MFJ 1699T Antenna
« Reply #5 on: March 11, 2022, 10:20:44 AM »

The big difference between the original LakeView Hamstick and the MFJ Hamstick is the way the tuning "stinger" was attached.  The Lakeview antenna had a metal ferrule with a setscrew to attach the stinger.  That meant if you broke down the antenna for transport, you needed an allen wrench and, you had to replace the stinger at the exact same position to maintain the tuning.  The MFJ has a two part ferrule which unscrews and allows the stinger to remain locked in the tuned position when removed for transport.  I had some of each brand and never found any difference in performance, on the same bands.
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