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Re: [Xylo-SDR] Some design thoughts requested
Phil
OOPS! Good thinking, they are a bit thinner. I've plugged enough in to know!
(my day job).
Would not be a good thing to have an oh! Oh Oh sh*!!!! I've also been
scouting pcb mfgrs in the past couple of days.
Eric
-----Original Message-----
From: xylo-sdr-bounces@lists.ae5k.us [mailto:xylo-sdr-bounces@lists.ae5k.us]
On Behalf Of Philip Covington
Sent: Tuesday, January 03, 2006 8:21 PM
To: Xylo-SDR Discussion
Subject: Re: [Xylo-SDR] Some design thoughts requested
The required board thickness is 1.27mm +/-0.10.
One thing to consider:
The thickness requirement might cause a problem with using some of the
prototype board services since a lot of them standardize on 1.60mm.
73 de Phil N8VB
On 1/3/06, KD5NWA <kd5nwa@cox.net> wrote:
> One advantage of the DDR size card is that if you don't need a large card
> it could be the size of a DDR module which is pretty small. You could fit
a
> SR5 and the bandpass module in one stick and still have a little room.
>
> There is a board thickness that you need to maintain in order to get good
> contact to the socket, I don't have calipers at home to measure the
> thickness of a DDR card, and see if that is a standard thickness.
>
>
> At 05:50 PM 1/3/2006, you wrote:
>
> Guys
>
> Done!
>
> Lets go DDR DIMM sockets. with a MB of our design. Now (or first) we
need
> an extruded aluminum (or other) project case with slides, in the size we
are
> talking about so we can define the board real-estate as default to slide
in
> the enclosure. Space on every few rails for a faraday shield between
boards.
> The PCI bus gave us cheap L-Brackets on a third side for connectors,
> however in this design everything must come out the 'front' of the box. It
> would be nice if we could design a 'front' panel based on a PCB which
could
> be drilled for common connector sizes and be reproduced for different
> projects. Heck, even a blank buss structured, motherboard, power
> distribution, project case of this sort could be a product with all the
> experimenters around!
>
> Sell this and fund our xylo boards! (smile)
>
> Comments?
>
> Eric
>
>
>
>
> ________________________________
>
> From: xylo-sdr-bounces@lists.ae5k.us [
> mailto:xylo-sdr-bounces@lists.ae5k.us] On Behalf Of KD5NWA
> Sent: Tuesday, January 03, 2006 2:44 PM
> To: Xylo-SDR Discussion
> Subject: Re: [Xylo-SDR] Some design thoughts requested
>
> That is workable for small boards, with .05" (1.27mm) pin spacing it's
very
> doable even with homemade PCB boards.
>
> Boards 5.5"x3.5" would be a reasonable board size, and with todays
> components you can put a whole lot of circuitry in a board that large.
>
> I've seen someone build a little jig to use a router to route the
connector
> and a belt sander to bevel the edge connector at home.
>
> I have not been able to find ready-made prototype boards.
>
> I've found an interesting source of IC header boards, reasonable when you
> consider the quantities you get.
> P516 and P507 look interesting.
>
> < http://www.beldynsys.com/singledual.htm >
>
>
> At 12:11 PM 1/3/2006, you wrote:
>
> Hello all,
>
> I considered using DDR SIMM sockets for a project. You get 184
> contacts and they give you a card width of 5.25". The height of the
> card is not restricted (within reason).
>
> http://www.molex.com/pdm_docs/sd/876362002_sd.pdf
>
> It is kind of like the SIMMStick idea, but with more contacts (184 vs
> 30). 30 pin SIMM sockets are very hard to get these days and I see
> that Molex has scheduled the 72 pin SIMM sockets for obsolescence.
> The DDR DIMM sockets should be around for a while yet. They are
> relatively cheap ($1.92 ea Digikey).
>
> 73 de Phil N8VB
>
>
> On 1/2/06, Eric Ellison <ecellison@comcast.net> wrote:
> >
> >
> >
> > Cecil
> >
> >
> >
> > Yes, I'll go back and look at Eurocard standard. This looks great. GUD
> > HUNTING! Thanks for all the links. One way or tother I think we need a
> buss
> > for our end product. Your point about size of the boards we might want
to
> > manufacture is well taken. They should be able to go on a little more
> than a
> > postage stamp, and be VERY inexpensive to produce - external connectors
> > being the limiting size factor! One reason I was looking at Memory Chip
> > risers.
> >
> >
> >
> > I moused around a little today, and really can't see where I can
justify
> > Eagle Software in any serious production version. So I'll probably
monkey
> > around with Kicad, which is a really nice GPL product. I mentioned
> earlier
> > that there was some problem with the Drill files, which they have
> corrected.
> > Only benefit of Eagle IS the plethora of template files available. I
> don't
> > mind eating on my lunchtime and creating new parts! Good exercise and I
> am
> > getting fatter! (No Testosterone!)
> >
> >
> >
> > Sparkfun has a pretty good batch deal for prototype boards and also a
lot
> of
> > interesting new products. I like their little 3 buck power supplies.
Also
> > have a some 28 pin SOIC to DIP experimenter stuff for about the same
> price.
> >
> >
> >
> >
>
http://www.sparkfun.com/shop/index.php?shop=1&cart=525299&cat=1&PHPSESSID=ab
ce58b426cb8d0d0c3cf4b1495f0312
> >
> >
> >
> > Other prototype boards can be had at:
> >
> >
> >
> > http://protoboards.theshoppe.com/index.html
> >
> >
> >
> > Will return!
> >
> >
> >
> > Viva the Project
> >
> >
> >
> > Eric
> >
> >
> >
> > ________________________________
> >
> >
> > From: xylo-sdr-bounces@lists.ae5k.us [
> mailto:xylo-sdr-bounces@lists.ae5k.us]
> > On Behalf Of KD5NWA
> > Sent: Monday, January 02, 2006 2:06 PM
> > To: Xylo-SDR Discussion
> > Subject: Re: [Xylo-SDR] Some design thoughts requested
> >
> >
> >
> >
> > I'll second the DIN connectors,they are very reliable, and come in
> different
> > sizes, single, and dual connector cards. I have used them in an
> industrial
> > environment and they worked flawlessly for years. But I'll go one more
> step
> > forward.
> >
> > The Eurocard standard allows for mix of one 96 pin connector, two
> > connectors or even three connectors (not needed). Prototype boards are
> > cheap, most PCB houses have specials on Eurocard size boards. Card
cages
> are
> > available for low prices for the Eurocard format
> >
> > Like Leon said the connectors are expensive but they are self
aligning,
> and
> > I've seen then for under $3 on the Internet.
> >
> > Although the PCI is tempting and cheap for the backplane, it's a bus
> that
> > is designed for digital logic, all pins are tied to the same pins in
all
> > cards. Prototype cards tend to be large and expensive.
> >
> > A brief blurb on Eurocards;
> >
> > < http://www.yotor.org/wiki/en/eu/Eurocard.htm >
> >
> > Cheap prototype boards are available for $10 or less, a very important
> > point, $50 to $60 for a PCI card is very expensive, maybe I'm too
cheap,
> but
> > the blank board should not cost more than the components.
> > < http://www.sbszoo.com/ve6sbs/sale/cct-brds.htm >
> >
> > Here are some available at Mouse;
> > <
> >
>
http://www.mouser.com/index.cfm?handler=data.getPcodes&pcode=BPS%2BPrototype
%2BBoards&pcodenumber=85400
> > >
> >
> > Sample enclosure, can be home made from aluminum extrusions.
> > < http://www.busboard.net/bps-enc.htm >
> >
> >
> >
> > At 03:34 AM 1/2/2006, Leon Heller wrote:
> >
> > ----- Original Message -----
> >
> > From: Eric Ellison
> >
> > To: 'Xylo-SDR Discussion'
> >
> > Sent: Monday, January 02, 2006 5:17 AM
> >
> > Subject: [Xylo-SDR] Some design thoughts requested
> >
> > Folks
> >
> >
> >
> > Even since the PIC 4550 days I have been thinking on how we might
conduct
> > experiments as well as have a reasonable environment for addingon to
the
> > project. The obvious answer is a buss of some sort. I have looked at
> > everything from Simm riser boards to ISA buss stuff. PCI risers might
be
> the
> > way to go since they are inexpensive ($15) for 3 slot extenders. Also
in
> an
> > end product they fit into the L-brackets of a computer case, or 2U
> mounts.
> > They have assignedpower busswe can use, fairly inexpensive prototyping
> > boards. ($50 - $60), are four layer and designed to minimize intra
trace
> > noise. The buss wouldnt be used for PCI, however it would allow power,
> (on
> > designated standards based lines), intra board connections, and FPGA,
> > I2C,signals etc.
> >
> >
> >
> > PCI seems to be a little largefor what we are proposing, and the
product
> > boards would cost more to produce, however, with an established buss we
> > could put a radio on one card, FPGA on another Audio on another etc.
> >
> >
> >
> > $15 Board amongst others:
> >
> >
> >
> >
> >
> > http://www.plinkusa.net/riser.htm
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > Am I off the wall here?
> >
> >
> >
> > That's the sort of thing I was thinking of doing. I used to work for
> Racal
> > and they used to build their military radios from separate screened
> plug-in
> > modules on a backplane.
> >
> >
> >
> > I favour DIN41612 connectors for this sort of thing. They are
expensive,
> > but very reliable, and have pins on 0.1" centres. They can even
> accomodate
> > co-axial connectors. They are more commonly used in Europe than the
USA,
> but
> > you can get them over there without any problems.
> >
> >
> >
> > 73, Leon
> >
> > --
> > Leon Heller, G1HSM
> > leon.heller@bulldoghome.com
> > http://www.geocities.com/leon_heller
> > _______________________________________________
> > Xylo-SDR mailing list
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> > Subscription help:
> > http://lists.ae5k.us/listinfo.cgi/xylo-sdr-ae5k.us
> > Xylo-SDR web page: http://xylo-sdr.ae5k.us
> > Forum pages: http://www.hamsdr.com/hamsdrforum/
> >
> >
> > Cecil Bayona
> > KD5NWA
> > www.qrpradio.com
> >
> > "I fail to see why doing the same thing over and over and getting the
> same
> > results every time is insanity: I've almost proved it isn't; only a few
> more
> > tests now and I'm sure results will differ this time ... "
> > _______________________________________________
> > Xylo-SDR mailing list
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> > Subscription help:
> > http://lists.ae5k.us/listinfo.cgi/xylo-sdr-ae5k.us
> > Xylo-SDR web page: http://xylo-sdr.ae5k.us
> > Forum pages: http://www.hamsdr.com/hamsdrforum/
> >
> >
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>
>
> Cecil Bayona
> KD5NWA
> www.qrpradio.com
>
> I fail to see why doing the same thing over and over and getting the same
> results every time is insanity: I've almost proved it isn't; only a few
more
> tests now and I'm sure results will differ this time ...
> _______________________________________________
> Xylo-SDR mailing list
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> http://lists.ae5k.us/listinfo.cgi/xylo-sdr-ae5k.us
> Xylo-SDR web page: http://xylo-sdr.ae5k.us
> Forum pages: http://www.hamsdr.com/hamsdrforum/
>
>
> Cecil Bayona
> KD5NWA
> www.qrpradio.com
>
> "I fail to see why doing the same thing over and over and getting the
same
> results every time is insanity: I've almost proved it isn't; only a few
more
> tests now and I'm sure results will differ this time ... "
> _______________________________________________
> Xylo-SDR mailing list
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> Subscription help:
> http://lists.ae5k.us/listinfo.cgi/xylo-sdr-ae5k.us
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> Forum pages: http://www.hamsdr.com/hamsdrforum/
>
>
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