An HF Go-Box for Field Day Featuring Icom's IC-7300 HF Radio and MFJ's MFJ-929 Tuner
Amateur Radio Emergency Services
A builders blog
AL5X Dave Lowrance Sitka Alaska 11 - 16 - 2018
Sitka Alaska is on Baranof Island, 90 miles long and 30 miles
triangular shape. We have 14 miles of highway and a few more miles of
mountain road. If you go out anywhere from town you will most likely be
on a boat or a plane.
Two other communities share the Island, Port Alexander, and Baranof Hot
Springs, along with some smaller aquaculture sites like Port Armstrong.
With the exception of a few local trails that terminate in canyons or mountain tops,
the terrain over most of the island is very remote and mountainous. While we have
4 repeaters for VHF UHF if you are near Sitka and have reasonable line
of sight, that mode is not really reliable for anywhere else on or
around the Island or two adjacent islands. 80 meters has been our best method in the past few
years for evening Nets, and some mornings we find 20 meters useful.
[Gator 6U (GR-6S) shallow version 14.25" deep]
I wanted an HF unit, well equipped, transported most
car or boat, at about 50 pounds or less.
Main importance, functionality and reliability, being able to
set up quickly anywhere if necessary for an extended period of time.
I settled on a gator 6U (GR-6S) shallow version
14.25" deep. It will fit on a table with room in front for paper work
or donuts and coffee.
It all just fits into the Gator 6U shallow box, with the connectors out the
back landing inside the rack area. I used a 90 degree elbow on the
IC-7300 HF Antenna port which may not be necessary.
IC-7300 radio with two 8 ohm MFJ cleartone speakers
set back into the case for a more large speaker sound.
The Icom IC-7300 has memory channels you can set up for all the
Nets, and step through them with easy up down arrows just above the
tuning knob, and on top of the mic.
These channels can be programmed with a USB cord to a laptop or PC, or from the front panel buttons.
The band scope will show activity across the entire bands
to spot anyone out there who would be active.
The IC-7300 will drive audio into 4 ohms or 8 ohms, so the
speakers can be bridged using a Y splitter [Monoprice 107203 3.5 Mono
Plug to 2 x 3.5 mm Mono Jack Splitter Adapter, Gold Plated] plugged
directly into the rear speaker jack.
2 each MFJ Cleartone speakers. Speakers were mounted on 1/4" spacers to bring them up to the radios
[Icom MB-118 optional mounting bracket]
Icom MB-118 optional mounting bracket for the
radio to be bolted down to the shelf firmly.
The AC power monitor at the top takes up 1U and is an APF
PS4X4pro, it shows the state of the generator power before
switching on the Alinco
power supply by using the meter preview key on the left side.
[DC powered LED strips]
The pull out light bars work off the 120 vac supply. 2 each 12 vdc "stick on" LED strips are added for lighting with a toggle on the back panel so we have emergency lighting from either AC or DC power.
Battery posts for external 12v battery with cut off breaker on the rear panels.
Checking the software revisions I discovered the radio was up to date.
I transfered the programing from my home base IC-7300 right into the Go-Box IC-7300 using a 32 GB SD card!
The front mounting hole strips and the upper and lower trim was
painted with a flat black spray paint, after carefully taping them off,
to match the panels.
[AC Infinity Vented Cantilever 1U Universal Rack Shelf 19" x 10.5"]
[Alinco DM-430T 30 Amp power supply]
[MFJ-929 autotuner] (two antenna ports)
[MFJ-264 1.5 kw dummy
The 1U 19 inch shelves are 10.5 inches deep and just fit the case with
1.75 inches spare to the rear to drop a wiring harness past before we run
into the rear panels.
The cable ties seem to be holding pretty well on this shelf , also was suggested using industrial Velcro to attach them.
Getting the IC-7300 to communicate with the MFJ-929
1 - If you want the IC-7300 radio to power up the MFJ-929 tuner
through the interface cable MFJ-5114I pull the cover off the box
and ensure [JP1 jumper] is installed. With that jumper installed you will
not have to run battery to the tuner independently. I had to solder a
piece of wire between the two foils on the board. The
location of these foils requires a thin solder tip and a steady hand,
as they are down near some components near the rear panel.
2 - Go into the [MFJ-929's software and configure it for an ICOM
radio interface]. Press the MODE button for 2 seconds to get into
this menu system then step down to the radio interface selection. See
pages 16-17 in the manual, which can be downloaded from the URL's below.
Showing all the connectors.
This is what the trim and mounting holes looked like before painting them black.
Showing the initial "testing phase" wiring.
So far I can still carry the box with one hand! 47 pounds.
Engineering the rear panels [11 - 18 - 2018]
[Resettable marine breakers from Blue Sea Systems].
A row of marine breakers along the top rear of the box. For reliability, leave no one time fuses in the system!
The IC-7300 has 25 amp
automotive fuses in it's power cord, replaced
with a [25 Amp marine breaker].
[External Battery Posts]
Battery posts on the back panel for attaching an external 12vdc car battery, with a shut off isolation breaker [Blue Sea A-Series Toggle Double Pole Circuit Breaker 30Amp].
[4 Aluminum panels].
AC Infinity Rack Panel Accessory Blank 1U and 2U 19".
panels are 2U blank or vented for easy removal and access, while the DC
power is controlled along the top 1U area , out of the way for access
of the rear components.
The lower 1U holding the lightening arrestor
for the antenna, a small ground bar, a USB port extender for
programming the radio or laptop control of operations, and some Key jacks for all possible key types.
Addition of a [MAGNADYNE Wall Mount 4 USB Charging Ports] unit for cell phone charging, with a [Blue Sea Systems Toggle Single Pole 5 amp circuit breaker] and internal led lights on the same breaker to reduce breaker count.
IC-7300 has a 1/4 inch stereo socket. My Bencher paddle key was modified
to a newer 3.5 mm jack for the Yaesu FT-891.
I would like the ability to plug in almost any key without messing with
wiring changes, so will mount 2 or 3 various jacks in a row on the rear bottom 1U panel.
[USB Programing Port]
[1 foot StarTech Panel Mount USB Cable B to B - F/M USB extension cables] for rear mounting the USB port in the rear bottom plate.
2018 - 12 - 1 Components arrived - Looks like they will
all fit in the 1U panel. LED strip in front and power socket above
so shelves can be removed without disturbing the "stick on" LED
2018 - 12 - 2 Components mounted into DC Panel.
DC Wiring Harness Diagram
11 - 19 - 2018
The wiring harness will route all the wires bundled up the
right side bottom to top. The upper panel can be swung out to the
right and attached with right angle clips for access and wiring.
If you are working on a 12 v external battery through the battery
posts, and there is no AC power, the Alinco 12 vdc supply will act as a
voltmeter. From the voltage you
can assess the battery state.
10 volts or below will do permanent damage to an automotive lead acid
battery. To fully charge it up 14.5 vdc is applied for a time of
equalizing then it is reduced to 13.8 to float. The unit can be used
as a battery charger, with voltage adjustment on it's front panel. This
is the reason to have one of the adjustable voltage supplies. A
low voltage alarm can be added across the power supply if desired for
an audible sound at a preset voltage, however the
digital voltmeter is on the front side.
With AC power applied, if the battery is very low, you can shut
down the radio equipment and reduce the voltage on the Alinco
charger bringing the battery up slowly. You can monitor the
current and keep the battery cool as it charges. A car battery can
be charged at 30 amps, automotive alternators are usually rated at
60 amps. The battery isolator breaker is sized to protect the
power supply during battery charging, as well to protect from fire from
battery discharge if there is a short in the power supply.
Note: The fuse was removed from the common battery lead to the
radio, but not to the external battery posts. If the polarity of
the battery is reversed, this will limit surge current to 30 amps then
blow the breaker between battery hot and cabinet ground.
1ea - Coaxial Lightening Arrestor PL-259 Sockets [Through panel mounting]
1ea - Blue Sea Systems Common BusBar 6 screw grounding [Mounted inside panel]
1ea - Grounding Post [sticks through the panel on both sides]
1ea - Through panel AC cord socket 15A 250V [Top Panel AC power cord is cut and soldered here, a new 10 foot 15A power cord with correct plug replaces it and can be removed]
2ea - AC Infinity Rack Panel Accessory Blank 1U Space 19" [Bottom and top panels]
Misc - Green Ground Wire
11 - 19 - 2018
I will update this blog as the build progresses!
Then I will set the unit on the scales and record the weight! LOL!
lot of the weight could likely be reduced by changing to aluminum
shelves I have no doubt, but I could not locate any at that size. [10.5
inches deep 1U or 2U 19 inch rack mtg.]
MFJ-929 downloads http://www.mfjenterprises.com/support.php?productid=MFJ-929
MFJ-929 descriptions http://www.mfjenterprises.com/Product.php?productid=MFJ-929
DX Engineering [ships to Alaska USPS] https://www.dxengineering.com/