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Cabinetry is pretty much required for a long term 24/7 packet radio node operation. Even a single port node will turn into an unworkable mess if it is not at least mounted so the individual parts are stable relative to each other. In addition, moving a packet node, when there are a dozen fragile pieces loosely placed, is impossible and likely to cause expensive and time-consuming adjustments to the placement. Just having everything nailed, screwed, taped, or attached with Velcro is a stunning improvement to the quality of life. But even more meaningful, is the consolidation of the entire package into an easily visualized, serviced, and conveniently placed piece of impressive (if not elegant) tech gear to compliment your hamshack.

Over the years several hams have built packet node cabinets and it is pretty clear that carpenter hams enjoy the challenge.

There are several different ways to go with cabinets. NC4FG, KM4EP, are involved in making the cuts for some really nice cabinets. Some of these cabinets are delivered fully assembled, others as kits requiring glue and sanding for final assembly.

If you are out of the loop with those hams, there are a few ways to go to create a serviceable physical structure to hold the nodes. The requirement is that the system, including power supplies, radios, Raspberry PI, TNCs, backup system, diplexers, adapters, couplers and whatnot, are all securely attached. A good rule of thumb is to imagine taking the entire thing on the road, hopefully to be handled with only 2 hands, and with the strong possability of inversion, i.e. being turned upside down.

If you are in need of a cabinet, or can make cabinets for people you have not met, send a query to the TARPN email reflector.

This page contains photos and close-ups of some of the cabinet designs, as well as a set of design notes from what we've learned about cabinetry as the TARPN project has proceeded. New builders of packet node cabinets would benefit from checking out some of the notes. Find the notes below the history photos.

If you already have a cabinet plan, here are some links to construction pages for outfitting your cabinet:
See also: Building the Control-Panel/Raspberry PI shelf
See also: Radio power supply and DC power distribution
See also: Mounting the radios and NinoTNCs

Photo Essay of TARPN Nodes, TARPN Cabinets, and Cabinet History

Most node builders, starting indepenently, will have the component parts laying on a bench. As soon as we realized that we needed a few operators to test networking concepts (or even to have fun with this stuff) we needed to deliver working solutions to their houses. That was the reason for the first boxes. Besides that, having 3 link-ports-worth of components laying around starts taking up lots of space. It's easy to see that all of this equipment is fragile if not housed.


KA2DEW (notacarpenter) node cabinets, 2013-2015, made with contractor screen and stacked TNC-PIs plugged into the top of the Raspberry PI.
June 2014 TADD node
1st TARPN wooden nodebox
July 2014 MOM node
Nov 2014 JENRET node
2015 TADD node
Jan 2015 SNELL node


After a half dozen nodes were assembled, we'd recognized the limitations of using the stacking connectors to pile TNC-PIs on top of each other.
•   not mechanically sound
•   LEDs and the potentiometers were not accessible after the units were stacked
•   hard to identify which TNC is wired to which radio
•   easy to plug stack into the Raspberry PI offset by one row or column of pins
Plugging the units in offset was a surefire way to destroy the Raspberry PI. This did not make us any friends.

The solution was to ribbon cable the TNC-PI together and arrange the TNC boards so the top of the board faced the operator but ribbon cables of longer than a foot or two were subject to RFI from the VHF radios.

It is worth noting that up to this point, all of the radios were connected to the TNC-PI using Mic and Speaker connectors and 1200 baud was the expected bit-rate.

When Fin NC4FG and Skip N6LUZ joined the project they applied their skills with power tools to create us some more practical and better looking cabinets. Our experience with the networking hardware was only a couple of years old so some of the features we'd later desire were not under consideration. We did know that unstacking the TNC-PI was a requirement, and that showing the association between the TNC and the radio was a high priority.

Skip was focussed on having the systems set up once, correctly, and to survive being tossed into a car for transport. He made us eight of his 4-port cabinets, and three 1-port nodes. These were the portable demo system of their day at a dozen club meetings and hamfest tables as well as in five permanent nodes.

SKIP node
ADRO node
FFVC node
FFVC node
TADD node, shown with 5 links and Oscilloscope
Stack of Skip-boxes
Stack of SKIP boxes
Slide-in guts of a Skip-box
guts of a SKIP box
Back of a SKIP box

NC4FG, Fin's boxes came next.
The one detail that nobody pointed out while Skip was making his first boxes is that cables would constantly need to be plugged and unplugged from the Raspberry PI. Fin moved to correct that in his first design. Below are pictures of several nodes using Fin's "box-1" four port node-boxes.
Drawing of the original concept
drawing of finbox1 493x380
FIN node.
This one was in CQ Magazine
March 2017 page 70
ANOIA nodexxxx TILL node


Most new participants in the project want to get the system working rapidly and the hardest part of that was having the radio/TNC levels adjusted well. The TNC-PI receive levels were more finicky if the signals were weaker. Optimum range was only granted with better matching of the receive and volume with the ideal voltage ranges on the modem chip. We wanted the ability to deliver a well adjusted pair of radio and TNC to a new operator and we didn't want the radio and TNC parts to have to be separated in transit. We also wanted everybody to have the tools to do their own adjusting for their later network adventures. At least for the newcomers, being able to add a pre-aligned radio/TNC-PI set to an existing node was a desired feature. We added an oscilloscope to some of the nodes and with the growth of the network, it was really obvious that we'd grown out of Fin's box-1 and Skip's robust portable node.

The new housing would have radio/TNC sets that were separable, but left the matched pair of TNC-PI and radio together in their own box so we could lend/borrow/exchange fully adjusted sets. We needed the Raspberry PI, power supply setup to include a monitor speaker and an oscilloscope so operators could have best-case access to tuning tools.

Fin worked for a couple of months on a new box to optimally support the TNC-PI. Fin called this the Stackable Modbox. Perhaps 100 of the boxes were made and deployed to 20 nodes and we had 3 different carpenters geared up to mass produce these things. This was a really huge effort by a dozen people to bring this together.
The stackable system was divided into 3 parts: basebox, tall radio box, short radio box. The base box had power supply for radios as well as a robust power supply for the Raspberry PI, a regulator to power the oscillscope, audio amp for monitoring the radio channels.
There were 3 different versions of the boxes, square-hole (1st), round hole (KM4JRH improvement), and butterfly bracket which was CNC machine cut (by N2IRZ)

xxxx xxxx
4 ports
KM4JRH's station with node box
Half the base-box guts. This is the view looking forward behind the Raspberry PI. Robust supply, audio amp and speaker lived here.
Half the guts of a basebox
    Behind-the-Scope guts
Half the guts of a basebox
2019 N2IRZ made his CNC machine cut an optimized stackable box
CNC cutting N2IRZ box
one unit, ready to assemble stackable box
CNC made N2IRZ box
one unit, fully assembled stackable box from CNC machine
CNC made N2IRZ box
2019 KC3IBN's Sandy node built in N2IRZ's CNC cut stackable box
All were rendered obsolete when the TNC-PI was discontinued months after we had acheived success with the Stackable Modbox.

In hindsight, coming up with those outrageous compensations to make the radios work with the TNC-PI should have been a clue. Just in the nick of time, Nino got his modem working.


Thanks to Nino KK4HEJ coming up with DSP code to perform the modem function in firmware instead of hardware, we can now do away with most of the debugging features we imposed on every node op for several years. The NinoTNC is tollerant of a wide range of receive levels and with a couple of more LEDs on the TNC we can tell if the packets are too loud or failing to be decoded. The new node-boxes do away with the scope and monitor speakers, as well as the explicit linking of one radio with one TNC in one cabinet. This is much cheaper to make, takes much less wood, and is much smaller.

The USB connection allows some versatility in TNC placement as well.

In 2020 Fin came up with Skelator to give visibility, ventalation, easy shipping (unassembled), and using very little wood. This has been made in wide, high, and small version. First box April 2021
FIN node
Hamfest Demo node
Jay KM4EP's 2nd node-box design has room for four links. First box April 2020
RUSSI node
ADRO node
Jay KM4EP's 3rd node-box design, "SideCar" has room for 2, 3 or 4 links depending on how it is built out. First box Nov 2020.
Demo node for Tadd's hamfest network
2022 Hector node
Jaybox for HECTOR

What does a Node Cabinet need?

Here are some ideas for cabinets. There are a few things that are must-haves.


Interesting cabinets and one-offs

People have been building custom node cabinets and interesting ways to tie down the equipment. Here are some photos and links:

In April 2014 we had a design for a 3d print 3-port node-box where the Raspberry PI, TNC-PIs would be in an enclosure. Steve W4RFQ did the CAD work. Before we could get the 3d-print related bugs out of the box, we realized that we needed better access to the controls on the TNC-PI. The 3d printed box added disassembly/reassembly time when making adjustments. Furthermore, the LED placement on the TNC-PI needed re-evaluation if placed in a 3d-printed cube.
3d print concept
3d print prototype
We did not go further. The concept could be repeated with NinoTNCs. I think we'd do 6 separate panels with nuts and bolts or snaps to attach the panels

Julio KW4WA's first node cabinet.

NC4AU and KM4IBM's node, two Raspberry PIs in a Jay KM4EP sidecar box. KM4EP cabinet, KA2DEW install.

Two port node mostly enclosed in a Phase Dock "Workbench"
Phase Dock

Micheal and Chris KM4DZP and KN4VOB from Winston Salem built a pair of demo nodes for the Science Bridge in April 2021.
KM4DZP Micheal demo node

Jay KM4EP joined our network with his own box in March 2020. Shortly after that he started making boxes for other node ops.
JAY node

In order to support a portable five station node, we needed three single-port nodes. The IKEA KNAGGLIG box fit the bill.
three KNAGGLIG boxes

Aaron, KF4EZU, nailed everything down to a plank. This was needed to fit in the upper shelf of a closet.
AARONJ plank node

WA3UTC made a fancy box with four TNC-PI.
Later it was used as a portable node.
© Tadd Torborg, 2014↝2022 -- all rights reserved