Portable Dummy Load Revisited 

I had made a portable 50 Ohm Dummy Load using an Altoids tin with six (6) 300 Ohm 2 Watt resistors in parallel.  This allowed me to test any of my QRP transmitters rated under 12 Watts such as my BITX40.

With the Xiegu G90 Transceiver rated at 20 Watts, I would have to be sure to turn the transmitted power down every time to use my old dummy load. 

I bought ten 510 ohm 3 Watt resistors.  I place two bundles of five resistors apiece, twisted leads together and soldered. After both ends of each bundle was soldered. I unsoldered the original six 2W 300 Ohm resistors and replaced them with the two bundles of five 3W 510 Ohm resistors. This should provide a 51 Ohm load with a max power rating of 30 Watts.

The Diode is a Schottky diode to rectify the RF signal to provide a measurable peak voltage at the banana connectors. Thus peak and rms Power can be easily calculated.
   

The inside of the Altoids tin with new resistors in place. 

73 AB1OP Ralph

AB1OP - 2020 ARRL Field Day

Objectives:

1. Xiegu G90 - Use the G90 in a portable operation.
2. LiFePO4 Battery - Test a 6ah LiFePO4 battery as an emergency power supply.
3. EFHW antenna - Build and use a multiband EFHW antenna for portable operation.
4. Anderson Powerpole Connectors - Convert all my field portable equipment to power pole connectors.
5. Downsize - Try to reduce / resize radio gear for effective portable operation.
6. BE SAFE & HAVE FUN!

Preparation:

Prepare Radio gear for packing.

 What I packed for Field Day:

 66 ft 18 ga wire for EFHW 40-10M antenna

50ft RG8X Coax PL-259 connectors (20ft close wound on a coffee creamer container - air choke)

49 to 1 EFHW transformer (a PL-259 and wing nut connectors)

Sling shot Antenna Launcher

Nextbook 7 Android Tablet for QSO logging with 5000mah USB battery Bank for recharge.

Backup Paper log in clam shell clipboard (black case under the tablet and power bank)

300ft Reel of 100# line for antenna deployment.(green reel) with spare line.

Small Tool Box (black w/ yellow handle)

Xiegu G90 20W 160-10M transceiver with power cable.

Small plastic Ammo box (30 Cal) for LiFePO4 battery box, cable storage, VOM, spare fuses, etc.

Xiegu G90 microphone. 

Bug Spray.

Golf Umbrella  

Deployment:

Radio gear as deployed

Xiegu G90 propped up on a plastic tub.

Battery out of the box for size comparison. Small black box next to tablet is a home brew battery monitor (mini LED voltmeter, 2 pair power pole connectors and two lengths of 12 ga solid wire, in an ABS box) 

Results:

I operated for 3 hours Saturday afternoon. In the first two hours I was able to log 9 contacts on 40 meters, then moved to 20 Meters and did not make any contacts in the remaining hour . My poor results I can only attribute to a reluctance of mine to jump into pile ups. My EFHW was almost completely vertical so that is why most of my contact were about 400-600 miles to the South West. I did have one contact to the East. (See attached Map)

I wasn't able to participate on Sunday. Family obligations and pending scattered thunderstorms in my area caused my early withdrawal. 

Conclusion:

I met every objective I had with the exception of working multiband 40 & 20 meters.

I was able to claim 168 points (9 QSO's X2 for Low power, 100 points for 100% emergency power and 50 points for Web submission of cabrillo log to ARRL. 

I was very happy with the VLS Logger android app. It was a smaller footprint, lower power option to bringing a laptop into the field for single op logging. 

I am thinking adding an optional bluetooth keyboard to the tablet, but I'm concerned on the tablet's power consumption. With wifi turned off and display at a readable daytime brightness I only operated 2.5 hours before needing to attach the power bank.

An objective for next year will be to resize my antenna to a smaller size more in line with my maximum 20W output. Shorter RG58 cables with BNC connectors, a smaller 49:1 Transformer and a 1:1 choke using RG172 and FT118-43 toroid core that would fit in a altoids size case using BNC connectors.

As Solar panels drop in both size and cost. Adding a solar panel and controller might be doable by the  2021 field day.

73 de AB1OP Ralph

Addendum:

Sample of my Field Day 2020 eQSL design. 

New Ham Antenna Launcher

Shelton 3.1 lite - Shooting position,  the pill vial is the steel stinker storage
Gorilla tape covers the 3 inch angle bracket leg that is screwed into the front of the Slingshot handle.
Gorilla tape also covers the leg of angle bracket zip tied to the pill vial and the Zebco 404 reel.

I 've tried several antenna launching systems over the years.  I think the first method was to put a handful of gravel in an orphaned nylon dress sock. Tie it on a string. Swing it around a few times (screaming like a chicken) and cast it into the trees. The cons of this method is you need to wear leather gloves to prevent rope burns, somewhat inaccurate and even a nylon dress sock hangs up in a pine tree sometimes.

Next I tried a collapsible backpack rod & reel with a 1 oz torpedo sinker. The reel was a Zebco 202. I spooled 20# test mono line until the reel was full. I had problems with the tall pines tress. The sinker would wind up just out of reach overhead, I would have to remove the line from the reel. Tie extra mono to allow me to reach the sinker. Remove the stinker, tie on the light hauling line. Pull the extra mono hand over hand back over the storage spool. until I reach the end that goes into the Zebco 202, retie the line onto the reel and crank the mono line all in. Finally getting to the haul line to actually raise the antenna. This system was also prone to having the sinker spin around a branch several times making retrieval impossible.

I broken down and purchased a JARC antenna launcher kit. The kit had all the PVC pieces to construct an air cannon launcher and two "pucks" to attach the mono to. I had to provide an air pump and a reel. I knew that the Zebco 202 was too lacking in line capacity.

I wound up buying a Zebco 888 preloaded with 110 yards of #20 test. I now could reach over those 100'+ tall trees my only concern was losing one of my two "pucks". The only time this system failed was when I broke the air pump and had to run into town to pick up a $12 replacement. 

After that failure and the fact that the air launcher was bulky and cumbersome. I decided to have a backup system that was more pack friendly if I wanted to do POTA or portable operating.

I remember George Thomas, W5JDX of AmateurLogic.tv and Ham Nation using a slingshot for his early ARRL field day ALtv videos. After a while I stumbled on N0KTZ "Rusty" youtube video that shows how he builds his "Shelton 3.0 Magnum" slingshot launcher which inspired my build.  https://youtu.be/ZtJvTQ2oogQ

    

My Three Antenna Launch systems

Screwdriver, Air gauge, Air Pump, "Pucks", 5 spools of cords
Air Launcher's large air chamber with ball valve
Air Launcher's Barrel with Zebco 888 attached
Backpack rod with Zebco 202 attached, rod holder
Torpedo sinkers, Snap swivels, 2 green Kite reels with 300' 100# line
Shelton 3.1 lite Slingshot with Zebco 404 and pill vial attached
4 one oz steel bass weights painted (fits in pill vial)
4 packs extra steel bass weights
MISC:
zip ties, 3in angle bracket, snips, extra mono line, gorilla tape
Storage box for Air Launcher
aerosol paint cans

I departed somewhat from N0KTZ bill of materials. He used PVC irrigation components brought from a "Big Box" stores. I used a 3 inch angle bracket and parts obtained thru my local Walmart.  I am calling my build the "Shelton 3.1 lite". 

My parts list follows:

• Daisy F16 Slingshot                                                      <$5 USD
• Zebco 404 spincast reel (w/ 75 yds #20 test mono)      <$10 USD
• 1 Angle Bracket 3 inch (comes 4 per pack w/screws)    <$3 USD
• Walmart Rx Pill Vial  (to hold sinkers)                          Free w/ Rx
• 3 zip ties                                                                          had on hand
• Gorilla Tape                                                                    had on hand
• 2 packs Eagle Claw Steel Bass Casting Sinkers 1oz.   <$4 for both packs

So my total was less than $25 USD, while at Walmart I bought extra steel bass casting stinkers and a sand rod holder to hold my kite reel to unspool while I'm hauling the line back over the tree from the other side.

Shelton 3.1 lite - Line retrieval made easier by holding the handle with the slingshot upside down

HF Antenna Maintenance

12 April 2020 - 18 April 2020

I had a long hiatus from posting my hobby blogs. My XYL's mother passed away last year and there didn't seem to be any excess time available to both do a hobby and post a blog. Just as things started to pick back up for us and we even bought a new dog the pandemic hit with social distancing, self quarantine and lockdown.

This year Winter's snow load was light, but we still had a several blustery days that took their toll on my 40 meter dipole wire antenna support ropes.  I had two separate failures one was the paracord supporting the feed point and the other was one of the mason lines used to tie down the "legs" of the dipole.  

This was my second (third?) Winter using these cheap support lines. So these failures were not unexpected.  The support trees were Eastern White Pine (State Tree of Maine) The deep corrugated bark abrades the support lines with each wind gust,  I decided to buy support rope that was designed for long term outdoor exposure and stop the false ecommunity of continuing using subpar lines.

Brought 500 feet of 1/4 inch Dacron rope. I hope this is about twice the length of what I need to support the antenna as a messenger line. I used my Joplin ARC antenna launcher (air cannon) to get one end of the line up and over the closest pine tree to the eastern side of the house.

I walked the rope end over and threw it up onto the back shed roof. I then used the antenna launcher to bring a haul line over an old snag in the old dog pen.

I then had to go onto the shed roof and haul rope to thread the eastern end insulator, the feed point assembly and the western end insulator. Pulling enough rope to make it up and over the snag limb with an additional 35-40 feet for raising and lowering the antenna to the roof.

I would like to say that things went smoothly but as often the case. If you're on the roof there is a problem on the ground and if you're on the ground at one end the problem is on the other end or back up on the roof.  This would have been easier with an additional helper or two. Not happening with social distancing. I did have my XYL act as a spotter with 911 on speed dial. I ended up doing this over the next few days when the temperature warmed up and the wind gusts calm down enough.

I then had to haul up one side of the rope then the other with the XYL checking to see if the dipole and rope would clear the radials on my VHF antenna mounted on the west gable end of the house.

With the dipole raised and the rope ends tied off, I could finally go into the shack and check out the performance. I had lengthen each dipole leg to the length recommended for mid-phone frequency. The best SWR tested was in the lower CW frequencies but it will do for now. I'm tempted to move the eastern leg of the antenna to a tree farther from the house, if I do I'll go for a better tune for SSB.
Until then I can finally get some more use out of my BitX-40.
73 de AB1OP_Ralph

Cribbage Boards No. 005 and No. 006

Cribbage Board Prototype No. 005

No. 005 is a 20 inch pine 3 track cribbage board.  Lettering was using water slide decals.

Games Won peg holes are on the end of the board as how the Rockler Template has placed them.

Pegs are cut from #10 finishing nails and painted 3x with cheap enamel nail polish.

Finish was two coats polyurethane wipe on, drying each coat completely overnight . Apply lettering waterslide decals, blot and air dry 3-4 hours, followed by two coats of spray on polyurethane (3-4 hours between coats) to protect decals.   

No. 005 with Games Won peg holes on the end.  Peg storage is in two  3/8" holes drilled into the side of the board, a turnbuckle cover turns halfway to open holes to access the pegs, turns halfway again to close. 

No. 005 Cover Closed

No. 005 Cover Open

No. 005 Bottom side with felt pads

Prototype No. 005 was my first attempt at lettering cribbage boards with water slide decals.  I found while finishing the boards with wipe on polyurethane after decals were applied may cause the decals to lift and stick to the wipe pads or brushes.  Spray on Polyurethane after applying decals gave the best results with two coats (3-4 hours between coats).

I am not really happy with the peg storage being 3/8" holes with 5 pegs in one and 4 pegs in the other.  Drilling the holes needs upmost care not to break thru the top or bottom surface of the board. I drilled the holes crossed grain from the side because I was afraid to split the wood drilling with the grain from the end.

Cribbage Board Prototype No. 006 

No. 006 is a 15 inch pine 3 track cribbage board. Lettering was using water slide decals.

Games Won peg holes were placed in the open spaces along the spiraled tracks. 

Peg storage was routed in the underside of the board using a 5/8" straight bit 1/2" deep, followed by a 3/4" dovetail bit 1/4" deep.  I tore the dovetail edge so I did a second pass and widen the dovetail to 1". I used two Jumbo craft sticks glue atop each other for the sliding storage door. 

Pegs are commercial pre-stained wood pegs that have 1/4" diameter heads and tapers to 1/8" points. It is a tight fit in the storage compartment with nine of these pegs. 

Finish was two coats polyurethane wipe on, drying completely overnight after each coat. Apply lettering waterslide decals, blot and air dry, followed by two coats of spray on polyurethane to protect decals.   

No. 006 showing water slide decal lettering  and alternate placement of the games won peg holes.

Bottom side peg storage compartment and lettering details. The compartment holds nine wooden pegs required.  Check out the use of jumbo craft sticks as the sliding cover.
Note: picture was taken before adding the 1" felt pads for each corner.

Thanks to my Rockler 3 person track cribbage template making hole placement easy.

A lot of lessons learned with this prototype.  Especially in using a wood router.  I got a WEN plunge router as the best value for money spent,  It has variable speed and soft start and I brought 1/2" shank carbide bits for it. I used only three bits the 5/8" Straight, 3/4" Dovetail (14 degree) for the peg storage compartment and the 3/8" round over with bearing for the edges.

If I were to do it over I would have gone with a one-handed trim style router using 1/4" shank bits.  The big WEN is great for cabinetry and moulding, but feel heavy and cumbersome on these small cribbage boards.