Dr. Ed Fong Antenna!

[cklima]

I recently ordered an Ed Fong GMRS antenna as I've heard many good comments regarding his patented antenna.  While purchasing my antenna, I communicated many times with Ed Fong via email and phone conversation.  Ed Fong is a professor of Radio Frequency at the University of California in Santa Cruise.  Dr. Fong's students build the antennas and also test many antennas manufactured by Tram, Larson, etc.  The UC has very sophisticated testing equipment and the test results of various brands are surprising. 

I asked Dr. Fong if he'd be interested in attending one of our weekly calls to discuss his experience as I think we could all learn from his vast knowledge.  Ed Fong is willing and would prefer a session via Zoom.  I'm currently checking his schedule but mid July, possibly July 11th, Ed would be available for this Zoom event.

Please let me know if you'd like to attend this Zoom event with Dr. Fong by replying with your email address.  I'll add you to the Zoom Invitation.

Thanks!

WRJD357

Clem

630-918-6938 (call or text)  

wrjd357@gmail.com

[axorlov]

Patented? Dr Fong patented a J-pole? Wow. I guess anything is possible with US Patent Office after some dude patented the windshield rain wipers...

Do you to happen have a patent file or number or name?

[axorlov]

WOW!! Dr. Fong did patent a J-pole! using a trap to electrically shorten the antenna!

8947313

J-pole with stubs, to be precise. Crazy! I guess anything is possible after some dude patented windshield rain wipers.

[SteveShannon]

35 minutes ago, axorlov said:

WOW!! Dr. Fong did patent a J-pole!

8947313

J-pole with stubs, to be precise. Crazy! I guess anything is possible after some dude patented windshield rain wipers.

Well, no, he didn’t patent the J-pole.  He has two patents that cover specific collinear combined j-poles for use on multiple bands.

https://patents.justia.com/inventor/edison-fong

He has 11 patents so far, with two of them being for his designs featuring collinear j-pole designs.

 

[axorlov]

Yes, to be be fair, the patent is about decoupling of two frequencies with traps. My original cry about patenting J-pole is wrong. Still crazy. This method of decoupling is known for longer than I live on this miserable planet.

[SteveShannon]

4 hours ago, axorlov said:

Yes, to be be fair, the patent is about decoupling of two frequencies with traps. My original cry about patenting J-pole is wrong. Still crazy. This method of decoupling is known for longer than I live on this miserable planet.

The vast majority of patents are based on new applications of existing knowledge. 

[axorlov]

8 hours ago, Sshannon said:

The vast majority of patents are based on new applications of existing knowledge. 

If only Dr Fong would patent the use of the 5 to 7 ferrite beads as a common mode current choke. This is what this specific antenna is seriously lacking. And this is why it is not suitable for the installation on the metal mast. Free idea for a patent: ferrite beads as a choke for the colinear 2- or 3-band J-pole made out of twin-lead inside PVC pipe. I'm sure USPTO will be glad to issue this patent.

[gortex2]

Lot of better antennas on the market for the same price

[TNRonin]

Lot of better antennas on the market for the same price

Not denying your statement, but I'm all ears. I need a GMRS antenna and thought this a good solution.

Sent from my SM-T860 using Tapatalk

[axorlov]

1 hour ago, TNRonin said:

I need a GMRS antenna

If strictly for GMRS, no ham, no MURS, no nothing and being a unity gain, I would recommend Tram Browning BR-6140. It is short, has a choke, comes with mounting hardware, N connector and is foolproof. It gave me years of service without any problem. Plug and Play in a best sense of the word, perfect SWR. It is sold everywhere and will be cheaper than Ed Fong antenna after you figure in choke and mounting hardware. If you want 2m, or 70cm, or MURS in addition to GMRS, or you want gain antenna, then look at theantennafarm.com. I personally have good results with Diamond X50, which is a ham antenna for 2m/70cm, but has acceptable SWR on GMRS (tad below 2). Some people here have good experience with Diamond X200 and X300.

There are also more expensive, more reliable antennas used for repeater service, remote locations, hurricane winds, snow blizzards, etc.

And, btw, BR-6140 works on 70cm too with SWR around 1.7. If you need 70cm.

[gortex2]

As above mentioned TRAM. The 1486 is a single band antenna and you don't have to go the HD or Lowes to try and find the proper PVC pipe. The Ed Fong requires the thin wall pipe and not the standard schedule 40 PVC. It varies by stores and locations. I have been in some areas that folks looked at me like an ghost and other that had racks of it. So the Ed Fong is $60 when it gets to you and you still need to go find parts. Not to mentioned there are a lot of NMO style base station adapter kits that allow you to test some various mobile antenna's which may be a better option. 

[SteveShannon]

20 hours ago, gortex2 said:

Lot of better antennas on the market for the same price

Whether that’s true or not, the purpose of this post was not to discuss the cost/benefit ratio of Ed Fong antennas, but to invite folks to attend a zoom presentation by Dr. Fong. Although I’m not the OP, I think we should respect the original poster’s hospitality. 

[dwmitchell61]

Ed Fong, PhD is an electronics engineer that is reputable and knows what he is doing. He developed these antennas from a request that he design an antenna given explicit criteria for a corporation in the communications business. There is no need to criticize unless you are willing to back your critique with explicit engineering facts. You don't have to buy Doctor Fong's products, but the proceeds do go to supporting the college students in his college courses.

As for the big brand name antennas, I would suggest you take the time to look inside the next one you buy before you put it on your tower or mast. You might just be shocked by what you find, and maybe even a bit disappointed if you know anything about soldering and antenna theory. 

I intend to purchase his antennas for my use when I go portable. I just don't want to have to carry around some 10 foot to 17 foot fiberglassed fragile antenna that could be broken, then spend another $200-300 replacing it.

Stay well, see you on the air, stay well and try to stay positive

73

Dave, KJ7WUZ/WRHW845