Randy shares experience with the MFJ-1899T and seeks “shady” advice

Many thanks to Randy (KJ4UBM) who writes:


Thomas,

I think you had said you were going to test the MFJ-1899T at some point.

I remembered I had one in a bin so I pulled it out, went to the local park and did some FT8 as my radiation test. All of the PSK reporter screen shots (below) are using the 1899T at 8 watts from my IC-703. I was pleasantly surprised at how well it did plus I was able to work several POTA folks from Texas to NY on voice still at 8 watts.

10 meters
15 meters
17 meters
20 meters
40 meters

All bands

I used my AX-1 with all of the same parameters and the 1899T had a slightly better footprint but spent most of the time using the MFJ today. I didn’t have a lot of time because the inter-galactic union of park mower dudes found out I was coming and of course had to mow this afternoon – go figure. I know you have the same problem. I guess that makes them really QRM(owers.)

I like to protect my whip antennae so I use 200 psi (thinner wall that the 400 psi) pvc pipe and end caps to store and protect while out and about with the whips.

I put a piece of pool noodle type foam in the end caps as a shock absorber. After set up the 1899 whip tube will fit inside of the 1899 base tube. The chameleon whips are in 3/4″ PVC, the 1899 whip is 1/2″ with the 1899 base in 1″ PVC. I thought I’d pass that little tidbit along in case you find it useful. The price is right and can be found at your local antenna emporium such as Lowe’s or Home Depot.

The black item under the home made antenna mount in the photo above is a QRP 1:1 balun by timortiz, N9SAB on eBay. He has several QRP antenna models which looks like Chameleon may be picking up his design in their pocket series?

Portable shade?

Maybe you can help with this one – I have been looking for something like a used stroller’s collapsible shade to keep the sun off a rig and laptop when used on a picnic table while allowing air circulation. A manufactured sun shade would look more “professional” and deliberate than the traditional card board box at field day, etc. Ideas?

 

73,
Randy – KJ4UBM


Thank you for sharing your MFJ-1899T results with us, Randy. And many thanks for the tips including the size of PVC you use to store your verticals. A brilliant and affordable solution!

I have started experimenting with the MFJ-1899T and will be posting a video in the next week or so. I’m still getting to know this antenna and, especially, sorting out how to reliably match impedance in the field without an ATU. 

You’re right about the N9SAB & Chameleon. They’re working together on the new pocket series antennas which are (as I understand it) the same N9SAB designs, but he builds them with Chameleon antenna components (ie Kevlar antenna wire, etc.). I should be getting one in due time to evaluate in the field.

Regarding tabletop shade, try searching for a “laptop tent.”

An example from Amazon. This one is called “Tech Shade To Go.”

I’ve got a friend that does video work that often requires editing on site outdoors. He has a portable laptop tent–his is somewhat reflective and allows for airflow–keeping sunlight off of his screen and his laptop much cooler than it would be exposed to the sun. Here’s an Amazon search showing a few different models (affiliate link), but look around on the Internet for a number of options. 

Also check out this previous post by Don (W7SSB). He’s been happy with a number of pop-up shade options, but mostly larger ones.

Readers, if you have other suggestions for Randy, please consider leaving a comment and links!

12 thoughts on “Randy shares experience with the MFJ-1899T and seeks “shady” advice”

  1. I have used closed cell foam pieces in the bottom of all my portable antenna poles to reduce the shock if the antenna pole collapsed without me being there to slow it down. It prevents breaking the bottom end cap.

  2. I have one of Chameleon’s Pocket Antennas, the 40 meter OCF. I’ve only had it out once, but it performed well. Most of my parks are 40-60 minutes away so I don’t get out as much. Hopefully next week I will get to a park.

  3. Great advice on the pvc tubing; I just received my Chameleon MPAS Lite and was thinking about options for carrying the whip. Another thought that came to mind was a bag of sorts for carrying fishing rods.

  4. With all that space in the park, all you can manage is that tiny, over priced back scratcher?

    You could have BUILT a decent antenna. Not a retractable whip stuck on top of a coil, and paid $150 for it.

  5. Thanks to all for suggestions. I had not thought of searching on tents for the pooch. I had seen the various A/V field monitor shades but was looking in true ham fashion – cheap/ repurposed with good air flow. I just found a shade on amazon to try.
    As far as this particular antenna test I wanted to try something small as a plan “B” antenna when traveling to locations where normal footprint radiators would be frowned upon or impractical. I usually have a DIY wire antenna hanging from a 31′ collapsible mast or trees which always work as my go-to. There is a lot of fun to be had in building baluns and ununs and antennas. The arborist throw line and antenna analyzer are true friends. My elmer is a DIY antenna builder and that rubbed off on me.
    I found K6ARK has a some ultra light weight DIY antenna designs that seem like fun to tinker with next.
    73 and Happy Thanksgiving to all!

  6. Looks excellent. I need to get out and make some use of my tripod+1899T for some casual and low-visual-impact operating. With the choke at your tripod, what length(s) of radial(s) did you use while operating across the five bands?

    1. To keep the variables as close to “stock”, I only used both of the stock AX-1 Counterpoise at the same time with both antennas- 1 x 17′ and 1 x 31′ So the usual multi length/ multi wire counterpoise set up was not used.

  7. Just a heads up the balun you have from Tim does not work as you expect. Its meant to go from a balanced load (dipole) to an unbalanced load (coax). I got one to work with end feds and had odd results and wondered what was up. After reading the manual and looking at the design it all made sense after I realized the difference between a voltage balun and current balun.

  8. Thanks Connor, In the past I had weird results with efficiency an tuning and put in a current balun in line and the problems “seem” to go away when using end feds and verticals. I will explore further and see if I just happened to be at a favorable node length. The reason I added the current balun to this set up was I was having RF and other weirdness which went away when I added the balun. Again possible coincidence in that one instance and not needed in the real world. I’ll do more due diligence in researching this instance with the little shorty antenna.

  9. Shade when setting up outdoors is another thing to carry. As such I look for something multi-purpose. Solar cell blankets, for example.
    Umbrellas are good, too. Sometimes I look at the arms of an umbrella, and think about quarter wave verticals…

    1. Oh, forgot to mention. It can also be used as a box for packing out lose items quickly if necessary. Who would have thought. Use a box as a box…

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