Tag Archives: Stubby 75

Mobile Install

I have taken my HF mobile install through a number of different iterations (the constant being the rig: an Icom IC-706MKIIG). Today I hope that I have finally reached a lasting, workable setup. Here is a quick re-cap of my trials and tribulations:

First attempt (2007):
What this install lacked in experience, it made up in effort. The successes were routing the powerline and the feedline. The antenna system was a different story. My combination of Hustler and Hamstick antennas (along with the unfortunate choice of putting an Icom AT-180 autotuner in the mix) met with mixed success. I did make contacts and enjoyed the mobiling. The rig itself was placed under the passenger seat. Placed side by side with my TM-D710A left very little room and little clearance between the seat and the floor. I came to realize that my 2005 Toyota Tundra lacked any real great locations to stash a rig. The drivers seat (no way), behind the back seat (nope), under the back seat (not going to happen).

Tarheel Model 75A and the stake pocket mount (2008):
I have not regreted going with the Tarheel Model 75A. I finally figure out that using an autotuner was a non-starter and a screwdriver offered a great solution. The stake pocket mount was a mixed success. The way the pocket was always had the antenna sticking up at a funny angle. It also did not seem very secure. I still made lots of contacts and had lots of fun.

Switched to MT-1(S) mount (2009):
Switching to the MT-1(S) mount did a lot to improve my operations. By having the antenna mounted right to the side of the bed, my ground (… and other half of the antenna) was greatly improved.

February 2010

Using the iPortable (2009-2012):
I don’t usaully have a passenger in the front seat – just two kids in the back. But having a heavy weight passenger in the front seat was a no-go for IC-706 in the all too cramped location under the seat. The iPortable setup allowed me to consolidate the IC-706MKII and the TurboTuner in one spot. No more messy nest of wires. But the iPortable offered somewhat of an obstacle to the kids in the back seat.

Current (…and final?) install (2013):
I have had the TM-D710A installed for a while. The AVMAP makes a good pairing and you can find my location via APRS here.

Now the iPortable is in the large tool box mounted to the bed of the pickup.

The big task was to reroute all the cables: an extension to the powerline, pulling out the feedline, and moving the control cable for the Tarheel antenna. The IC-706 includes the AD5X fan modification.

I had to drill a hole on either side of tool box to route the cables in and out. So far, so good – everything works and I am getting a full 100 watts out on every band.

I did forget to run a line for a CW paddle… that is on the To Do List.
There are also a few additional improvements I would like to make.
- 12v booster to 13.8v
- Extra 12v battery
- amplifier? :-)

Armed Forces Day Crossband Test

I had a fairly successful day participating in the Armed Forces Day Crossband Test. To recap, I am currently at Fort McCoy, Wisconsin for a brief period of time supporting a National Guard exercise. Normally when I go around to different Army units and assist in their exercises I fly. But I decided to take my Toyota Tundra on this trip and re-installed my HF rig. I have never preiously particpated in the Armed Forces Day Crossband Test and have always wanted to…. this was my chance.

The AFD Crossband Test has two components to it. The first is to receive a message from the Secretary of Defense which is transmitted in various digital modes from different military stations during the day. The second part of the Test is to make contact with the military stations with the military stations operating in their band and the amateurs in their band (hence the term “Crossband”).

For the Secretary of Defense message I hooked my Rigblaster Plug & Play to my IC-706MKIIG and brought my laptop into the truck (which has fldigi installed). The Rigblaster worked like a charm and I was able to copy the SECDEF’s message from WAR (at The Pentagon), AAZ (Fort Huachuca, AZ), and AIR-2 (New York). All these transmissions were in RTTY, which fldigi was able to read without issue. Now I need to print out copies of the messages I copied (which are the same, except the header information which reflects what station was transmitting the message) and send them in to the corresponding station. In return, I believe, I’ll receive a certificate from the SECDEF (suitable for framing, I’m sure).

The crossband contacts caused me to take a crash course in split frequency operations for my IC-706MKIIG. Fortunately I had my Nifty “Cliff Notes” version of the manual and was able to figure it out pretty quick. Although the actual execution took a bit of time to get down. First, obviously, I had to hear the station calling. MARS HQ publishes ahead of time a list of each station and the frequency that they will transmit from. I built a spreadsheet that allowed me to sort by frequency which made it easier to search for the transmitting station. The searching was done in the IC-706MKIIG’s VFO A. Once I found the station, I had to listen for them to announce the amateur frequency they were listening to… which most stations did periodically. Once I got their listening frequency, I flipped over to VFO B, dialed up the frequency, tuned the Tarheel screwdriver antenna, flipped back to VFO A, then hit the Split function, and waited for a chance to call. In the end, I was successful in contacting five different stations: WAR (at The Pentagon), NWKJ (located on the USS Yorktown, Charleston, SC), NMN0CQQ (located on the USS Midway, San Diego, CA), AAZ (good ol’ Fort Huachuca, AZ), and NWVC (a Navy MARS station in Indiana). For these contacts I get to send in my QSL card and hope for a response.

None of this was exotic DX but it was fun and exciting… and a bit challenging trying to do it all from inside my Toyota Tundra. I hope I am able to particpate again next year.
















On The Road Again

When I left for Korea, I had to pull out the HF installation on my truck… as the truck was staying in Kansas and I was not. Pulling out the rig and tuner was easy. The Tarheel antenna was also fairly simple. A disconnect at the base and then I coiled up the feedline and the cable that powers the screwdriver so they would be mostly out of the elements.

I returned back to Kansas last June but did not reinstall my HF setup in the truck. My only real modification was swapping out my VHF/UHF antenna with a fold-over. The new house afords me the opportunity to park in the garage(!) but rather than unscrewing the antenna every time I enter the garage, now I just have to pull it down. Works great.

My assignment here in Kansas has me traveling quite a bit and this week I am headed up to Wisconsin. I have only driven through Wisconsin once so instead of flying, I am going to make the 9 hour drive. This had me thinking that if I am on the road for 9 hours, I need my HF rig. So today I put the radio back in and reattached the Tarheel antenna.

Everything was set – I fired up the rig and heard the Turbo Tunner beep that it was on and ready. I hit the 706′s tuner button but the screwdriver failed to turn. Troubleshooting time. I took the base of the antenna down to the bench. Then I dug out the original rocker switch that came with the Tarheel. I hooked it up to the bench power supply and then hit the switch. Nothing. After a bit of jiggeling and wiggeling, the screwdriver engaged. I guess the almost two year siesta had taken a bit of a toll.

After a test drive today, it appears as if the mobile HF rig is working FB!… one QSO with North Carolina and another with Massachusetts. So look for me (AD7MI-9) as I make my way to Fort McCoy, Wisconsin and maybe I will catch you on 20M.

Mobile install

I have my HF mobile up and operational again. The setup I had last summer was with a stake pocket mount with my Tarheel Stubby 75 towards the rear of my Toyota Tundra’s bed. The problem with the stake pocket mount is that the Stubby 75 kept coming loose. I ordered the MT-1(S) mount from Tarheel. I had the MT-1(S) mounted on the inside of the bed of the truck towards the rear. The trick is getting the thing secured to the side. For this task I enlisted the help of the local body shop which did the job for under $40. The mount and antenna are now incredibly secure. I have to redo the PL-259 connector connector from the feedline to the base of the Stubby 75 – should have time to do it after school on Friday. Oh… and this picture is not actually of my install but thought it looked like some good intentions gone wrong. I will try to take some pics of my mobile install and post them this weekend.
In other news… EI9FVB emailed me confirming his receipt of his YI9MI QSL card. That’s great – hopefully the others will be receiving their cards soon (if not already).
… last but not least, it looks like the ARRL store has field day shwag for sale.

On The Road Again!

It was good to get back behind the wheel of my 2005 Toyota Tundra – although can’t say I am excited about paying to fuel it up. I’ve attempted to get a good HF install for mobile operations before experiencing limited success… with perhaps my biggest rookie mistake being an attempt to use the ICOM AT-180 autotuner along with my IC-706MKIIG.

I used Hamsticks and Hustler mono band resonators – it worked pretty well but I got tired of having to exit the vehicle every time I wanted to change bands.

My answer was to install a screwdriver antenna. I’d been planning this mobile install for some time, using lessons from my trials in the Spring of 2007 as well as a significant amount of reading and research (eHam, WorldRadio, CQ Magazine, websites). I decided on basing my mobile install around the Tarheel Model 75 “Stubby” providing continuous coverage from 3.7 to 34 MHz. The folks at Tarheel worked with me to get me going – responsive to my emails and questions.

The radio for this mobile install: my ICOM IC-706MKIIG. I’d originally purchased this radio when I arrived in Hampton back in the early Summer of 2005. The purchase was in part to motivate me to upgrade from Tech to General – which it did. That Summer I passed the written exam (Element 3) at a nearby hamfest for General. But I was not yet ready for the Morse (Element 1). It wasn’t until later that Fall that I was ready for the Morse… and barely passed too. I’ve been very pleased with the IC-706MKIIG; it is a great radio for a beginner, easy to operate, solid performance, flexible to use either in the radio shack, portable, or mobile.

To mount the antenna to my Toyota Tundra, I really did not want to permanently mar the exterior of the truck. I’d admired K4GUN’s install and thought his implementation of using the Geotool stake pocket on the bed of the truck was brilliant. I wrote Steve, K4GUN, concerning his install and he provided some great additional information concerning the challenges of the stake pocket mount. After working with Rick, WA6JKH, to ensure I was ordering the proper mount, I placed my order and Rick gave me a nice active duty military discount.

I decided to get N2VZ’s Turbo Tuner for ease of operation. Operating HF while driving is already complicated enough and I wanted to make tuning the antenna as easy as possible. Bill was very responsive and also provided a military discount.

I had ordered all the equipment while in Iraq, so everything was waiting for me when I arrived home.

The install took two days. Perhaps the hardest part was mounting the IC-706MKIIG under the passenger’s seat. Already installed under the seat was my ICOM IC-208H – my trusty VHF/UHF rig. I’d originally installed this rig during my circumnavigation of the continental US back in 2005. During that install, I only partially removed the passenger’s seat. This time I pulled the seat completely out of the truck which greatly helped me successfully position both the IC-208H and the IC-706MKIIG in the limited space.

Routing the feedline from the rig to the stake pocket mount was fairly easy, making use of the rubber grommet directly under the passenger’s seat and zip ties along the feedline’s path to the rear of the truck. Soldering the connections to the stake pocket mount was straight forward but it was a bit tricky feeding the line up through the bottom of the stake pocket.

Setup of the Turbo Tuner was a snap; I followed the provided instructions step-by-step, making sure I had the DIP switches positioned properly.

Mounting the antenna onto the Geotool stake pocket mount was made easier by using the HI-Q’s Giant Quick Disconnect. Payment was via PayPal and Charlie, W6HIQ, had it on my doorstep within the week. Thanks Charlie!

How does it work? So far, so good. More reports from the road are coming… and maybe a picture or two.

Toyota Tundra Mobile Installation


Steve Clifford (K4GUN) on August 8, 2007

I recently purchased a new truck and installed two radios. The install went so well that I thought I’d post an article with details on what was used and how it went.

First of all, the truck itself really helped make this possible. It’s a 2007 Toyota Tundra 4×4 with the 5.7 liter V8. I chose the Double Cab model over the Crew Max for a couple of reasons. First, the bed is 6.5′ long instead of 5.5′ on the Crew Max. The Double Cab also has better storage under the backseat, as we will see shortly. The truck also has two small holes in the back of the cab that are covered with rubber plugs. The holes are not large enough to fit a 259 connector through and require unbolting the rear seatbelt and pulling off a plastic cover.

My first project was to install an auxiliary battery. For this, I chose an Optima Yellow Top size 31. I put it in a cheap battery box to which I installed a Rig Runner 5 outlet panel. To charge this, I needed a battery charging system. I did a number of searches and found one that is sold through an eBay store. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120146674911This is the one of only two parts that I didn’t install myself. I work at a car dealership and had one of my technicians install it. He had no problems and the instructions are very clear and simple. The kit includes everything you need to hook up the spare battery. The unit isolates the main truck battery for the first 5 minutes after start up before it allows current to charge the auxiliary battery.

The battery itself is mounted in a toolbox in the bed. I decided to get a steel box instead of the normal aluminum because of the weight. Steel boxes will rust quickly if scratched so I applied a coat of spray-on bedliner.

Battery in the tool box:

Battery isolator:

Next up are the radios themselves. I installed a Kenwood V708A and an Icom IC7000. Both fit in the center console of the Tundra. I’ve had people ask me about the heat from the Icom and so far, this hasn’t been a problem. I’ve been keeping an eye on the temperature indicator and it hasn’t gotten too high. If this becomes a problem, I’ll put another hole in the bottom of the console and install a fan.

The Icom head unit is mounted on the center console with a Portagrip model 717. For details, see page 38 of the current HRO catalogue. The Tundra has an auxiliary plug for audio and I ran a short cord from the head unit into this plug. The factory speakers make for very clear HF audio. The only down side to this is that I also have Bluetooth which interrupts the radio whenever a call comes in.

The Kenwood head unit is mounted in the overhead console. It’s also a Portagrip but the model 726, which is a much shorter arm. The wires are run through the overhead console and around the windshield. The Kenwood supplied cord was not long enough to make it all the way to the base unit. It turns out that this cord is nothing more than a modular phone line with a special plug on the head unit end and a regular phone connection on the base unit end. I used a regular phone line coupler and extension line to get to the head unit. Because regular phone line is not shielded as well as the Kenwood cord, I used a DX Engineering Ferrite bead. I don’t know if I needed that, but I have no RF issues so I’ll leave it. Because the Kenwood requires the microphone to be connected to the head unit, I had to drill a hole in the console to get the cord out.

Here is the Kenwood in the overhead. Since taking this picture, I have routed the wire inside the console. It doesn’t hang out now as is shown in the picture.

Here is the console with both radios, a storage bin and my other truck accessory

Here is another shot with the storage bin removed. The bin does not crush the wires. I drilled the hole to get the wires out.

The wires are routed to the back of the cab. The Tundra comes available with a storage bin under the back seat. I ran the wires under this and then routed them to the panels with the hole to the outside.

Next is the antenna system. For HF, I went with a Tarheel Stubby 75 with a fold-over for the 5′ whip. I originally had it set up with a Tarheel cap hat, but removed it when I discovered that I couldn’t tune 40 meters with it on. Strangely, I could tune 75 and 20, but not 40. I did not get any type of auto tuner for the antenna and instead just used the rocker switch from Tarheel. It works well and is easy to tune. I may eventually get a Turbo Tuner but am not in a rush for that.

I don’t plan on using the UHF or VHF very often on the Icom but I did want an antenna connected so I put a magnet mounted Diamond NR770 on the tool box. Because the connector would not fit through the hole in the truck, I had to cut it off and reattach it once it was routed into the cab.

The other antenna is a Diamond SG7900, which feeds the Kenwood. It’s a big antenna but actually looks small next to the Tarheel. It also has a fold-over for parking garages.

Last, let’s talk about the antenna mounts. At first, I thought I could get away with one of the rubber friction stake pocket mounts. I attempted to install one and quickly discovered that the stake pocket was just too big. I then contacted Geotool. Geotool makes several mounts and they are specific to different trucks stake pockets. The new generation Tundra takes the same mounts as the Ford so if you order from him, don’t get the older Toyota mount.

The Geotool mount is very solid. The coax is routed through the body of the bed and is soldered directly to the mount. It bolts to the bottom of the stake pocket and if you scrape off the paint, you probably don’t need additional grounding. I scraped paint but also installed grounding straps. Here is a link to Geotool: http://www.geotool.com/antmount.htm Be sure and tell him if you need this for HF or VHF use. The bases are different and I have one of each.

While I’m very happy with the installation, which is very clean and tidy, the real proof has been the performance. I’m still quite new to the hobby so I often don’t really know what to expect. I have a station in my house and have some power line noises that I’m trying to work out. I was stunned at how much I could hear on the mobile unit. Not only could I hear, I could be heard. I immediately started trying to jump into some DX pile-ups and was happy to see that I could get through fairly easily. In the first week, I hit Argentina, Ukraine, Moldova, Cuba and several Central American stations. I got signal reports from 5-8 to 5-9 with a couple reporting 10 over 9. I even heard a Japanese station, but didn’t have time to try and make contact. All of this while driving 70 miles an hour down Interstate 95 in Virginia.

This radio is working so well that I often will turn off the home radio and go sit in my truck for an hour or so. It doesn’t do much for my gas mileage to be sitting there idling for so long, but the joy of the hobby is worth it.