Saturday, April 10, 2010

Comm Academy 2010 Portable Radio Contest - K7RFH Radio in a Box Entry

Today I attended for the first time, the Communications Academy 2010. Having my Amateur Radio License since December 2009, it was a real challenge to come up to speed fast enough so that I was able to create a "radio in a box". Just finishing the radio only about 2 weeks prior to the Comm Academy's start. All in all, I am very proud of the outcome. The following information was provided to the contest organizers.

Purpose of Project:
The original purpose was to provide a radio system that could go anywhere, yet be stored easily in a compact space. This project morphed into a portable radio shack to be used for EMCOMM, Field Days or home base station. Requirements were to be able to run using any adequate power source in fixed, mobile or portable modes.

Capabilities Available in Package:
Current total weight of this unit is 27.5 pounds (12.5 kilograms)
The portable shack is designed for use on AC or battery power. Power options include providing power output to charge handhelds, run power inverter or powering a secondary external radio. Power is regulated using the Super Powergate 40S so with battery connected, auto failure is provided and battery is charged when AC is available. System power is provided by the FT-897’s FP-30 power supply.
Yaesu FT-897D can operate on all Amateur Radio Bands in a variety of modes. Local Emergency frequencies are preprogrammed in the FT-897D. Onboard antenna tuning is provided using an LDG AT-897Plus
Signalink provides soundcard based digital operations capability.

Deployment Process:

Deployment steps:
1. Connect power source(s). AC, battery or both.
2. Connect required antennas
3. Connect ground wire
4. Power on and operate radio

Optional deployment steps:
1. Connect computer to CAT and Signalink (marked TNC) cables
2. Start software on computer and operate radio

Design Features:
Unique modular open frame design provides easy access to equipment for maintenance, modification and inspection. Aluminum framing significantly reduces weight. Cooling is provided without the need of powered fan because of open over/under air paths. Sound chamber style layout means no external speaker is required.

Other features:
• Separate HF and VHF/UHF antenna inputs
• External grounding block
• Cigarette lighter DC power output
• Powerpole DC power output
• Powerpole battery power input
• Power monitor displays power consumption and charging reference.
• Time of day clock
• Laptop/document storage compartment

Secondary power box provides battery power via Anderson Powerpole connections.
Starting at the top right and moving clockwise, the power box presently contains all manuals needed, 200W power inverter, powerpole cigarette lighter socket, 2 - 12V 7.0 AH batteries, MFJ SWR meter, rollup 2 meter antenna, rollup 6 meter antenna and the power box itself.  The tray contains a spare Yaesu microphone,  LDG 4:1 Balun, Yaesu compatible headset, cheap set of earbuds and tape measure.  Not pictured is a 12V AGM 135 AH battery.

Radio carrying case is weather resistant SPUD-7 MTM Case Gard. Lid can be used to hold documents or provide some weather/sun protection. 
Additional Comments:
Pictures demonstrate equipment’s easy separation from carrying case; layout of components and simply, clean design elements.
Additional items available – equipment user manuals, coaxial jumper cables, variety of connectors/adaptors, SWR meter, antenna analyzer

Antennas to be used:
• 2 meter J-pole roll-up
• Dual band (2 meter/440) aluminum J-pole
• Dual band (2 meter/440) mobile mag-mount
• 300 Ohm twin lead 6 meter vertically polarized omnidirectional end-fed antenna (roll-up or fixed)
• G5RV-lite dipole 80 meter-6 meter
• 40 meter Tak-Tenna

Links to related material: THE BOX: PORTABLE EMERGENCY COMMUNICATIONS STATION IDEAS Hints and tips for your GO-Kits Emergency Ham Radio Portable Go-Kit Revealed Building a Go-Kit Emergency Amateur Radio Communication Kit by KH7O HAM Radio Emergency Go-Kit presentation Benicia Amateur Radio Club (BARC) ARES Boom Box A RADIO GO BOX OR PORTABLE EMERGENCY COMMUNICATIONS BY David P Schornak N1IB

Several people have asked about where the MTM SPUD 7 box came from, so here is a list of the various parts and where to get them:

MTM SPUD 7 Case: OR Sinclair International
Powerpole parts and other power accessories:
Aluminum framework parts and other hardware: My local Home Depot

Download the PDF brochure for my creation, which was given out at the radio contest.

Update 5/20/2010: Just found this article about another SPUD-7 based Go-Kit
Update 12/5/2010: Found another Go-Kit Radio in a box article

Update 4/19/2011: Recently, Shane Cruze wrote to me and had some great questions that weren't answered in the information above. So I thought I would share the questions and answers with everyone here.

Update 3/29/2015: Revised configuration.  Only minor surface changes.

Q: Where did you get the front mesh? I can find the aluminum angles, etc at Home Depot but could not find the mesh.

A: The perforated aluminum was the hardest to find, but we have a local hardware store called McClendon's Hardware that basically is the place you go when you can't find it anywhere else.
The to finding it online is the terms "perforated aluminum". carries it

Q: How do the roll up antennas work for you?

A: The TV antenna wire J-Pole roll-ups work okay in a pinch, however, I haven't needed them yet. I can connect the box using standard mag-mount antennas in the car, in the EOC and at home. One of the antennas I like for 2M and 70cm is the EE-3
It is definitely an in-the-field style antenna for light duty use.
I am still researching a better roll-up style 6M antenna.

Q: How did you connect the 12V feed from the radio's AC power supply back to the Powergate?

A: Connecting the 897's power suppy required getting and extra connector and installing Anderson powerpole connectors to the other end. Or I found later that you can buy them from Powerwerx pre-mode.

Q: Can you say more about how the Powergate is wired to everything?

A:All connections use Anderson Powerpole connections, bulkhead adapter and/or splitter.

External AC runs from front bulkhead into FT-897D power supply.
Power supply output runs into Powergate "PS" connection.

Powergate "BAT" connection runs to the battery IN Powerpole bulkhead adapter's lower connection

Powergate "OUT" connection runs to a Powerpole fused splitter. It has one input connection and three output connections. Each output connection runs to the one of the following:
- FT-897D power input
- bulkhead cigarette lighter adapter
- Powerpole bulkhead upper connection

With these connections you can attach an external battery which will run the "box" when no AC is available or the battery will be charged if AC is available. The Powerpole bulkhead 12V out connection can be used to power another radio or radio charger.

Q: I bought the identical SPUD case so that I could duplicate your setup exactly. Do you happen to remember the dimensions you cut the aluminum angles as well as the flat strips? Do you also remember which screws and the size holes drilled in them?

A: The key was to make the face plate fit as snug as possible. The dimensions are:
Faceplate: 16" x 11" (Rounded corners) Rear: 13 3/4" x 9" Sides: 12 1/2" long
As I understand from others, sizing is a little variable with the boxes, so customized fitting is needed.
Wherever possible I used aluminum pop rivets. I don't recall the size, but probably 1/8 inch. Any screws, bolts and nuts used were those that came with the equipment.
The tricky part is aligning the shelves so that the knobs, etc don't hit lid when closed. Lots of trial and error adjustments to get it right. I used screws initially to allow for adjustments then replaced with rivets for final assembly.

Q: Did you get your grounding block (s) inside the box and on the front panel from Home Depot also or did you get that from an electrical supply?

A: Yes, I brought two sizes from Home Depot and used the longer one. Only ended up needing the shorter one since only 3 ground wires needed (1-897D, 2-AT897, 3-faceplate grnd). Also discover with second box that the chassis itself is a ground, so grounding block was just an extra but convenient ground. The faceplate grounding terminal has a matching one on the inside of faceplate. Again, overkill, a bolt holding terminal through faceplate would have worked fine to attaching wire.

Q: Did you use a flat black paint or a glossy?

A: Neither, I used a textured or pebble finish. It gives it a more "equipment" look.

Q: Did you get the strain reliefs for the accessories that attach to the perforated aluminum at home depot as well?

A: No, most of the little stuff came from Harbor Freight or Radio Shack or my "parts" drawer.

Q: Were you able to use tin snips to cut the aluminum or did you just use a hacksaw and sand down the edges afterwards? Did you just punch out the holes for the accessories on the perforated aluminum?

A: Yes, snips to cut the perforated aluminum. Hacksaw and grinder for framing. All holes were drilled. Larger holes were Dremeled out. Don't have a punch.

Q: I assume you used 12 gauge wire for all your connections?

A: Yep, from Powerwerx, red/black 12 gauge zip cord

Some other thoughts and additions for future modifications:

Added 12V LED light bar from IKEA

Laptop section in the top will later be changed over to hold Signalink, power monitor, clock or maybe another radio for doing dedicated sound card digital. Found that I carried the computer separately and the size has dropped significantly with the purchased of a netbook.