[hpsdr] Pandora Enclosure Project Proposal.

[Ben Hall]

Good day all,

I am Benjamin Hall, KD5BYB, the project leader for the Pandora enclosure 
project.

WHAT IS PANDORA?

Pandora is a collection of “Lego Building Block” like parts that can be 
utilized in the construction of an enclosure for an HPSDR.  The Pandora 
name is taken from the old story of Pandora’s Box.  One particular 
telling of the story states that Pandora’s Box was a holding vessel for 
all of the misfortunes of mankind.  However, Pandora opened the box, and 
all the misfortunes came out.  However, Pandora was able to close the 
box quickly, and hope stayed inside.  It is hoped that since Pandora has 
let all the evil out of the box with hope remaining inside, our 
Pandora’s box will have already had all of “smoke” let out, leaving only 
hope and goodness inside.

The proposed parts, as a starting point, will be:

1)  An End Panel.

The End Panel is a rectangular, flat metal plate (currently around 5.5 
inch tall, 9.3 inch wide, and 0.062 inch thick).  This plate will 
contain slots like you’d find on the back of your desktop computer. 
There will be six slots, one for each card that Atlas can accept, with 
the 0.8” center-to-center spacing found on the Atlas board.

The End Panel will have provisions to attach metal Close Out Strips with 
cut-outs matching the connectors found on cards designed for Atlas.

The End Panel will have provisions to attach a Bottom Plate, so that one 
could use an End Panel and the Bottom Plate as a non-enclosed home for 
an HPSDR.

Additionally, the Bottom Plate and the End Panel could be incorporated 
into a user-supplied case.  Metal working tools available to most hams 
prohibit the accurate cutting out of thin openings like one would find 
on the back of a computer.  However, a rough-cut hole, large enough to 
provide clearance for the HPSDR circuit boards is easily cut with a saw. 
  The End Panel then provides a very clean way of hiding this rough-cut 
hole.

The End Panel will be a drop-in replacement for the end panels found in 
a commercially available case.  (The Ten-Tec BK-959 case is currently a 
front-runner and appears to have room for six 220 mm long cards, but may 
lack room for front panel controls when fully populated with 220 mm long 
cards.)

2)  Close-Out Strips.

The end panel will have provisions to attach metal Close Out strips with 
cut-outs matching the connectors found on cards designed for Atlas. 
Think of these strips as the metal L-brackets on a standard PC card, but 
without the short piece at the top.

3)  Bottom Plate.

The bottom plate will have provisions to accept an Atlas card and 
provide provisions for mounting the bottom plate to the End Panel, 
allowing alignment of cards plugged into Atlas with the slots in the End 
Panel.

NOMENCLATURE

 From this point forward, “Pandora” will be used to refer to the 
collection of parts as well as a complete enclosure that could be built 
from the parts.  This is sort of odd, referring to a collection of parts 
and a completed enclosure with one term.  But, it's convenient.

WHY IS PANDORA A BUNCH OF PARTS?

Simply, to allow each HPSDR owner to buy on the parts they are going to use.

In doing the groundwork for this proposal, user input was solicited as 
to what sort of form should Pandora take.

When users couldn’t agree on which was the front of an Atlas/Janus/Ozy 
stack, it was clear that there were many, many ways people wanted to use 
and house their HPSDR.  This is not a complaint, but part of the vision 
of the “have it your way” HPSDR experience.

With a building block concept, users can use the parts they want and not 
use the ones they don’t.

WHAT GUIDELINES ARE BEING FOLLOWED?

The Pandora design is going to be an attempt to hit a moving target. 
There are cards currently undergoing design and test as this is being 
written.  Therefore, unfortunately, the Pandora design will somewhat 
constrain card design.  Its hoped that these constraints won’t be too much:

1)	Atlas will be the “backplane” card for Pandora.
2)	Pandora will accept cards no larger than 100 by 220 mm.
3)	Pandora won’t be able to house an amplifier or other card with 
significant (say >100 watts) heat dissipation.  (Discussions already 
point to a future power amplifier requiring a power supply in excess of 
what Atlas can support.)
4)	Pandora will try to be as friendly as possible for non-USA HPSDR 
users.  Ideally, this will include selection of a commercial enclosure 
available outside the USA.  If not, the parts will be made as flat as 
possible for the lowest cost in mailing.
5)	Pandora will try and minimize the amount of custom-made parts and 
focus on what can be obtained off the shelf.  The US Government calls 
this “Commercial Off The Shelf” or COTS.  This term may find its way 
into Pandora discussions.
6)	Pandora will allow for easy access to the cards contained within with 
minimal disassembly.  It is expected some users will use Pandora to 
house future HPSDR prototype cards.
7)	Pandora will follow the standard HPSDR procedures.  It won’t be 
designed in a vacuum and user input will be sought.
8)	And as always, it should look nice!

FUTURE CHALLENGES

As Pandora is hitting a moving target, it would be nice to know what 
HPSDR card developers are thinking in regards to:

1)	Power consumption / Heat dissipation.  So far, with Ozy/Janus, this 
appears to not be a big deal.
2)	Card size.  Right now, Ozy/Janus are on the smaller end of the 
possible sizes for cards.  If future cards are going to trend closer to 
the 220 mm maximum, this would be good to know now.
3)	Power supplies.  If a pico ITX power supply is used (see 
www.mini-box.com), very little dedicated space is needed for a power 
supply.  If something larger will be the norm, the enclosure size may 
have to grow.

Even if the above information is just a guess, it will help greatly.

Thanks much and 73,
Ben, KD5BYB, kd5byb at bellsouth.net
-- 
Thanks and 73,
Ben, KD5BYB