Selecting an enclosure is an important first step in building a µBitx. If you don’t already have an enclosure, this will be the most expensive additional part that you need to buy to get your uBITx on the air. That said, many µBITx have been assembled on the bench, with no case and operated for weeks or months before migrating to a case!
Dimensions
The main board is made from a quality FR4 fibreglass/epoxy PC board with plated through holes. Board dimensions are 6″ wide by 5 1/2″ deep. An additional 1/2″ minimum depth is required to mount the Raduino on the front of the main board.
The height of the enclosure must be at least 2 3/4″ if you are using the suggesting mounting arrangements for the main board, Raduino and display. If you separate the raduino from the main board or if you use different hardware to mount the main board, then it may be possible to get away with slightly less case height. Check out another simple, but ingenious idea for lowering the overall height of the µBITx here.
The edges of the main board contain tracks that are not at ground potential. It is advisable to allow a further 1/4″ or so on each side of the main board for clearance if you are using a metal case.
The mounting holes are 7/32″ in from the edges, or 5.0625″ and 5.5625″ between hole centers.
An enclosure is linked to how you will use you µBitx
Your use case may constrain the form factor for your µBitx or the materials that you can use to make it.
- If you are planning to use your µBitx for mountain topping (e.g. SOTA) or for rugged outdoor use, then a small lightweight enclosure will be what you want.
- If you are using your µBitx alongside other transceivers (e.g. in a contest situation), you will almost certainly be looking for a metal case to reduce the chance of damage from radiation in the shack and to reduce IMD products.
- If you are wanting to extensively modify your µBitx, you will need to choose an enclosure that leaves plenty of room for modifications to be built alongside the main board or, alternatively, sufficiently tall to be stacked on top of the main board.
Consider case material
The most popular housings used by home constructors are made of plastic. Creating holes in a plastic case is so much easier than for any metal case (even aluminium cases). Ordinary hand tools (a hand drill, reamer and file) will be adequate, although obviously lightweight power tools would make the job quicker. A plastic case can be lined if necessary with copper tape, available ex China or from your local stockist. Copper tape can be bridged between adjacent layings with solder to create a fully screened box quite cheaply.
A second approach that has become popular with home brewers is to build a custom case from either single-sided or double-sided PCB. These cases are lightweight, provide full screening from other RF sources and can be quite affordable.
Aluminium cases are the next preferred option in the “weight” and “ease of construction” stakes. Aluminium cases are generally light-weight and more robust (but not necessarily more robust than a good plastic case). Aluminium is generally easy to work with (at least compared to other metals), but filing work on the display surround will take a bit more time than with a plastic case. Keep this in mind!
Mostly you will want to avoid steel as a material for your enclosure. Difficulties in creating holes in the steel, will soon convince you that steel is not the material of choice for amateur radio projects. The exception may be a case that has steel top, bottom and sides, but with aluminium front and rear panels. However, these cases also tend to be heavy! If you want a boat anchor, steel is the way to go.
A number of constructors have repurposed existing cases from old transceivers. Many of these may be in the “boat anchor” category, but updating to a uBITx brings new life to an old favourite!
Finally, you may want to consider a Pelican-style case (such as those available from Harbour Freight – almost always “on special”) or other cases that offer travel protection.
A popular plastic case for the µBitx
The Excellway® EF01 Electronic Project Case is a popular choice (purchased through Bangood.com) for around US$10 when on special. The dimensions of this case are 200x175x70mm. The case will accept either of the Bitx40 or µBitx kits.
If you are using the Excellway EF01 enclosure, you should consider purchasing these rather nice 3D printed front and back panels from Jim AG6IF.
These panels will circumvent forming holes on the panels, and give your rig a very professional finish:
See https://www.ebay.com/itm/362218558429
W5BEK 3D printed case
Carl Beck W5BEK has a rather nice 3D printed case that can be purchased. Check out Carl’s case in the news article here. Unfortunately Carl is now SK and this case is not available to purchase.
Other plastic case options
If you are in Britain, Australia or New Zealand you could use the following instruction case, available from Jaycar in Australia and NZ (called Pro Quality Instrument Case 253 x 190 x 82mm). In the UK, this can be ordered from Maplins.
This case gives you plenty of room to accommodate modifications. The next size down works with the Bitx40, but is too small to accommodate the µBitx main board.
Popular aluminium cases
Hammond cases are a popular option for µBITx constructors. The picture above is for the Hammond 1402d case (2.38 in x 7.13 in x 7.25 in (60 mm x 181 mm x 184 mm). The photo below reveals the tight fit of the main board in an installation by Dave WI6R.
Reference
This Hammond case has sufficient height (but only just) to mount the Raduino while attached to the main board if you do not use the 1/2″ mounting hardware. Other Hammond cases will more readily accommodate the µBITx.
Another option is the Circuit Specialists LA6 aluminium instrument enclosure
Yet another option is the Jameco 208929 (7.3″ x 6.3″x 2.75″) or the Jameco 209358 (7.5″ x 9.8″ x 3.2″).
And another solid option from Fry’s
And one used by a list member and documented here.
Sunil VU3SUA who is an active BITX20 list constructor has a business (Inkits) selling enclosures and electronic components for the Indian domestic and international market. Sunil is now shipping his µBITx case. This is a high quality metal case that is available in several colours: Maroon, Black, DA Grey, Siemens Grey, and Blue.
The universal case for the µBITx costs US$34.99 with worldwide shipping via India Post costing US$20. DHL courier has an additional charge of US$15.
For international orders from https://amateurradiokits.in/
For Indian domestic orders, go to http://inkits.in
Reusing surplus cases
Many constructors have found new uses for old cases. You may, for example, be able to find old computer switch boxes (originally used to switch several computers to a single parallel or serial printer). These are typically made of steel but have reasonably unblemished front panels. You may need to, however, replace the rear panel.
Pelican style cases
Brien, K7XPO has put his µBITx inside a Pelican-style case with a rather “classy” military look (knobs still to be added):
