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Portable Ops #ubitxv6 #portable


Aaron K5ATG
 

For years now I have been loading up my Elecraft K2 or KX3 on a bike to go operate from one of the many parks around my house. Last year I upgraded to a recumbent trike, and now I am close to using my uBitX V6 as my main rig for here at the house and portable at the park.  My Elecraft rigs both have internal batteries my uBitX does not. For my uBitX I will be using battery packs made of 8 rechargeable AA batteries and a small solar panel. I'm kind of limited on what I can take as everything will have to fit in my saddlebags because using my bike trailer can sometimes be a hassle. 
I know I can't be the only one that uses a uBitX portable so I was wondering what your portable setup is like. 
--
'72
Aaron Scott
QRPARCI# 16443
GQRP# 16389
4SQRP # 1080


Vic WA4THR
 

I use a small 12v Lithium-Ion battery pack, a Talentcell 6000mAh unit from Amazon, that comes with a wall-wart charger and connecting power cable that plugs right in to my uBitX. It has powered my unit all day without running down and might even be installed inside of the case. For antennas, I used to set up a hamstick on a metal stake driven into the ground, but then I switched to a portable mag-loop made by Doxytronics on a small tripod. It works from 80-17m and testing using extended WSPR reports show it is equivalent to the hamstick but with a slightly lower take-off angle and requires no tuner. The whole package (rig, power, antenna, mini-tripod) fits in a small cloth briefcase that is easily carried, and what I used in the last Field Day. Here is a picture of the setup from the 2020 FrostFest and you can see the antenna and the battery pack. The tripod is a larger unit than I carry in the pack.


Aaron K5ATG
 

That is a pretty nice setup. Could you take a pic of your case, it looks pretty nice. 
I currently use a homebrew Buddipole and that gives me 20-10. I use the higher bands the most. When I want to get on 40-80 I use an MFJ endfed that is about 140 feet long. I'm always playing around with portable antennas. My current project is using two 23' telescoping fishing poles in a dipole configuration that will support regular-sized wire dipoles for 30-6 meters with no tuner. The downside to it is I have to have a dipole for every band. I'm thinking about making it a linked dipole with small connectors or switches. I support it with a 16-foot painters pole that is bungied to my trike and it uses an Armstrong rotator 
--
'72
Aaron Scott
QRPARCI# 16443
GQRP# 16389
4SQRP # 1080


Jonas Sanamon
 

Hi Group and Aaron,

I use my uBitx's mainly for portable use.  The alu-box Nextion equipped uBitx is a version 3 and the black 3D printed enclosure with original display is a v.4 with added audio amplifier and Makita 18v LiPo battery holder. Both of them has the DSPmeter extra nano CPU. 
IMG_5677.jpg
IMG_4965.jpg

For portable setup I have 3 different home made antennas that I use as inverted-V:
1) Resonant 80m shortened dipole (length 2x 8.5m / 28ft)
2) Resonant 160/80/60m trap dipole (length 2x 12m / 40ft)
3) Double zepp with ladder feedline, balun and Icom AH-4 tuner. LiPo 4 parallel x 4 series 18650 cell box (under radio) and Tuner control box is visible on top of uBitx here:
IMG_6304.jpg

For erecting the antennas I use
1) Slingshot to get a line over a tree and hoist the centre antenna isolator to at least 7m (23 ft) height. 
or
2) Glass fibre Nato tent pole surplus 1.2m (4ft) poles, usally with 1 supporting line + the dipole legs to hold it vertically.

IMG_5740.jpg
IMG_5739.jpg


I have also just built a small portable N7DDC tuner that I have yet to test in the field. I had room for 3 x 18650 LiPo cells in the tuner box as well. I got the tuner from RA0SMS on ebay and already had the 0.91" OLED display.  I measured the idle current of the tuner to 25mA so I hope to get many hours use out of the batteries, but time will tell:
IMG_6435.jpg
73, Jonas - SM4VEY


Den sön 11 okt. 2020 kl 21:01 skrev Aaron K5ATG via groups.io <k5atg=yahoo.com@groups.io>:

That is a pretty nice setup. Could you take a pic of your case, it looks pretty nice. 
I currently use a homebrew Buddipole and that gives me 20-10. I use the higher bands the most. When I want to get on 40-80 I use an MFJ endfed that is about 140 feet long. I'm always playing around with portable antennas. My current project is using two 23' telescoping fishing poles in a dipole configuration that will support regular-sized wire dipoles for 30-6 meters with no tuner. The downside to it is I have to have a dipole for every band. I'm thinking about making it a linked dipole with small connectors or switches. I support it with a 16-foot painters pole that is bungied to my trike and it uses an Armstrong rotator 
--
'72
Aaron Scott


Vic WA4THR
 

Thanks for the comments about my uBitX, Aaron. I used an Excelway case from Banggood as I had picked up a couple when they were on sale for $8 and had used one for my BitX40. I inverted the case so the vent grille can be used as a speaker grille, and the mounting posts are available for top-mounted items (only the speaker in mine) while providing a smoother surface for other circuit boards on the bottom. I also added some rubber feet so the handle could fold up flush when not used as a stand. Having to carry a hamstick for each band, and actually needing an antenna tuner to work when off the hamstick tuned frequency was another reason I switched to the loop. While I have a small auto-tuner that runs off the uBitX power, this way there is one less thing to carry. I have added the SWR bridge and indication mod to the Nextion display so I can confirm proper tuning of the Loop. Here is a larger picture of the rig.



=Vic=


Frank Dinger , EI7KS
 

Aaron , Instead of using AA batteries ( I presume you mean NiMH type) I would consider a few 18650 type Li-Ion cells which can be fitted into clamp holders (max 4 in 1 holder) You obviously would need a voltage equalising board , but all those items are low cost and available from the usual asian on-line suppliers.
The actual battery 18650 cells can also be retrieved from old laptop battery packs . Pretty surprising ,these retrieved cells often have a lot of "juice" left and when fitted into clamp holders can be easily replaced .  
Such a home made battery pack is very compact/ low weight  and has a high Ah capacitiy when compared with NiMH units.

Frank   ,     EI7KS


Aaron K5ATG
 

Jonas,
I like the aluminum case, the 3-d printed one looks cool. Is the Makita powering the UBitX?
I also have the N7DDC Tuner for the UBitX. I don't have it finished yet, I am making a case for it from PCB board and I need to order some buttons for it. I literally finished installing a Nextion on my BitX this morning, I don't have any extras for it as I am still learning it. 
--
'72
Aaron Scott
QRPARCI# 16443
GQRP# 16389
4SQRP # 1080


Aaron K5ATG
 

Vic,
Your case is pretty sharp. 
One thing I love about the uBitX and BitX is the creativity. You can find 500 IC7300 or KX3 and they will all pretty much look and operate the same. You can find 10 uBitx or BitX's and they will all be different. These little rigs have some character and some soul to them. 

Frank,
Yeh I use cheap Westinghouse brand AA Ni-Ma 2000 mAh batteries. I think I found a deal where I got 40 batteries for $20 back in 2015 and I have only 2 batteries go bad since. This is the battery holder I  use

It has a plug on the short cord that fits perfectly in my radios and an on and off switch that I use then they are not in use. They were a few bucks on E-bay and I take a few with me when I go operate portable. A single pack is not going to last all day long and it is what it is so you have to have realistic expectations on them but they can do the job. I don't know how well it will work on my uBitX because I suspect that the Nextion is a bit power-hungry.
I have no experience with the 18650 cells but giving them a quick look shows a lot of options for them.
--
'72
Aaron Scott
QRPARCI# 16443
GQRP# 16389
4SQRP # 1080


Jonas Sanamon
 

Hi Aaron,

The aluminium case is the Hammond 1455T1601 which is a nice size, but really a tight fit for the uBitx. The board need to sit sideways (I have Radiuno on right side and IRF510 on left side), and the height is so low that I need to bend the pins on the Radiuno to 45 deg in order for it to get under the lid. I have a piece of copper plate screwed to bottom of case on left side that the IRF510 transistors are screwed into for cooling. I feed the raw voltage from LiPo battery pack( approx 18v) to the PA and have a 12v linear regulator (planning to replace with a switch mode when I find one sufficiently QRM-free) also on the copper plate to get the voltage down for the 12v part of the radio. I have also moved the 5v linear regulator to the back plate for better cooling (also thinking of a switch mode replacement here)
Photo from inside during assembly, You can see copper plate and radiuno angle;
image.png


Yes, the Makita battery powers the uBitx. Works for hours of portable use, and its easy to have a replacement in the pocket. Handy if you already have their tools and batteries + charger (recommended by the way, I've used my "impact screwdriver" and drill for years and thousands of holes and screws, still works perfectly and is strong as an oxe)

The case is 3D-printed from this design: https://www.thingiverse.com/thing:2925336
The Makita battery holder is 3D-printed from: https://www.thingiverse.com/thing:352094  

I'm considering installing a N7DDC tuner inside the 3D-printed black enclosure. It wont fit inside the Hammond case unless I remove the speaker.
The black case has a small CPU-fan that cools the IRF510 heat sinks, it's running half speed in RX and full speed in TX-mode.  It has a LM386 module added for more audio volume, can be seen on manhattan-style PCB to the right. Copper plate installed for heat sinking of 7812 and 7805 Linear regulators:
image.png

Cheers, Jonas - SM4VEY


Den mån 12 okt. 2020 kl 20:26 skrev Aaron K5ATG via groups.io <k5atg=yahoo.com@groups.io>:

Jonas,
I like the aluminum case, the 3-d printed one looks cool. Is the Makita powering the UBitX?
I also have the N7DDC Tuner for the UBitX. I don't have it finished yet, I am making a case for it from PCB board and I need to order some buttons for it. I literally finished installing a Nextion on my BitX this morning, I don't have any extras for it as I am still learning it. 
--
'72
Aaron Scott