On Jul 28, 3:59 am, "G \"Guglielmo\" Evans G4SDW"
wrote:
Does anyone have experience and/or recommendations
for analogue and digital I/O interfaces based on the Universal
Serial Bus (USB)?

Just an idea for the genesis of a homebrew spectrum analyser.

Ive done a little with USB, so I'll add a little background if not
provide complete answers.

The first hurdle is the interfacing. You need a board with a driver
thats easy to interface with your host PC software program.
Ive used a board from www.mirrorbow.com for general control...you can
access it every 1mS and get 12 x 12bit ADC samples for each access, or
you can alter 8 bit digital ports etc. However, the speed is limited
to how fast the operating system can access the board, which is 1mS.
This board pretends to be a com port so it makes programming easier
without needing to include libraries and dlls etc.
Theres a board from National Instruments which I think is faster,
though only around 2.8Msamples/sec http://sine.ni.com/nips/cds/view/p/lang/en/nid/202596
And of course there are some dedicated USB spectrum analyser
available, but thats not the same as doing a home version.
So, you could just get a DAC board and go for it, though the speed you
can make a spectrum analyser is limited.

Of course you could use the superhet principle with a narrow band
filter and a programmable LO. You could then use a simple IO board
like the one from Mirrorbow to setup the LO, then use a peak detector
and the boards AD to give an indication of level. You'd then have a
digitally controlled analogue spectrum analyser, and you woudlnt need
the large sample rate.

mirrorbow is not a bona-fide operation and does not advertise its
address, directors and other information as now required
by UK law.

"bigorangebus" wrote in message
ups.com...

The first hurdle is the interfacing. You need a board with a driver
thats easy to interface with your host PC software program.
Ive used a board from www.mirrorbow.com for general control.

The jobless bar steward wrote:

mirrorbow is not a bona-fide operation and does not advertise its
address, directors and other information as now required
by UK law.

Well, why don't you e-mail them and tell them what you read in your £350 law
book. There are two e-mail addresses on their website. I'm sure they'd be
delighted to hear from you as much as we are.

Better still, GET A JOB.

"G "Guglielmo" Evans G4SDW" wrote in message
...
mirrorbow is not a bona-fide operation and does not advertise its
address, directors and other information as now required
by UK law.

That is a little odd. Any idea why they aren't more forthcoming?

On Jul 30, 6:05 pm, "Joel Kolstad"
wrote:
"G "Guglielmo" Evans G4SDW" wrote in ...

mirrorbow is not a bona-fide operation and does not advertise its
address, directors and other information as now required
by UK law.

That is a little odd. Any idea why they aren't more forthcoming?

I received both the boards I ordered from Mirrorbow in a few days and
all my email enquiries were answered extremely quickly and
thoroughly. I guess they are not a multinational, and Ive never had
cause to ring them. However, payment is via Palpal which I believe
offer a degree of protection anyway. My invoice on delivery had their
address on it.

There are lots of companies online that dont show addresses or phone
numbers online, so I cant believe it is illegal not listing them!
Otherwise all those webspace providers would be breaking the rules!

I think its a silly to post a comment stating that they are not "bona-
fide" unless you can post evidence to suggest this.

Twice I sent my money via paypal, and twice I received my board
quickly and it worked to spec. I had questions, and they were
answered on email.

If we expect every company we deal with as amatuer electronics
enthusiasts to have a call centre and list streams of directors I
think we would find them thin on the ground in our specialist area!

"bigorangebus" wrote in message
oups.com...
There are lots of companies online that dont show addresses or phone
numbers online, so I cant believe it is illegal not listing them!
Otherwise all those webspace providers would be breaking the rules!

I think its a silly to post a comment stating that they are not "bona-
fide" unless you can post evidence to suggest this.

The evidence is their web site which does not comply with UK law
as to revealing the business address and names of directors.

On Aug 5, 4:59 pm, "G \"Guglielmo\" Evans G4SDW"
wrote:
"bigorangebus" wrote in message

oups.com...

There are lots of companies online that dont show addresses or phone
numbers online, so I cant believe it is illegal not listing them!
Otherwise all those webspace providers would be breaking the rules!

I think its a silly to post a comment stating that they are not "bona-
fide" unless you can post evidence to suggest this.

The evidence is their web site which does not comply with UK law
as to revealing the business address and names of directors.

Do you have a web link to information on this requirement? I'm
curious.

How do businesses operate that are partnerships or sole traders? It
is not a requirement for a business in the UK to have directors, so
how can they all be required to show them. You're suggesting you have
to be a limited company (they have directors) to trade on the net....

On Aug 6, 5:23 pm, bigorangebus wrote:

Do you have a web link to information on this requirement? I'm
curious.

http://preview.tinyurl.com/2fbnzy

David

on 05/08/2007 16:27 bigorangebus said the following:

If we expect every company we deal with as amatuer electronics
enthusiasts to have a call centre and list streams of directors I
think we would find them thin on the ground in our specialist area!

and VERY expensive!
--
;-)
73 de Frank Turner-Smith G3VKI - mine's a pint.
http://turner-smith.co.uk

On Aug 5, 9:04 pm, Cheemag wrote:
On Sun, 05 Aug 2007 08:27:19 -0700, bigorangebus
wrote:

I received both the boards I ordered from Mirrorbow in a few days and
all my email enquiries were answered extremely quickly and
thoroughly. I guess they are not a multinational, and Ive never had
cause to ring them. However, payment is via Palpal which I believe
offer a degree of protection anyway. My invoice on delivery had their
address on it.

There are lots of companies online that dont show addresses or phone
numbers online, so I cant believe it is illegal not listing them!
Otherwise all those webspace providers would be breaking the rules!

I understand that the law in the UK requires that they show at
least an address and telephone number if the website is located
here.

--

73, Jim, G4RGA

Rally Info:http://www.g4rga.org.uk

I didnt imagine putting this very helpful company in my post was going
to create so many problems and I feel a bit guilty now!
I found this on the web:
***************************************
According to Outlaw, the following is the minimum information that
must be on any company's website.

* The name, geographic address and email address of the service
provider. The name of the organisation with which the customer is
contracting must be given. This might differ from the trading name.
Any such difference should be explained ??? e.g. "XYZ.com is the
trading name of XYZ Enterprises Limited."

It is not sufficient to include a 'contact us' form without also
providing an email address and geographic address somewhere easily
accessible on the site. A PO Box is unlikely to suffice as a
geographic address; but a registered office address would. If the
business is a company, the registered office address must be
included.
******************************************

I sent it to mirrorbow and they said they would put an address up on
the contact page http://www.mirrorbow.com/contact.htm so it should be
there by the time people read this. The company is privately owned
and does not have directors apparently, and they said that they didnt
post an address as they do not have the facilities to receive
customers.

I would recommend you email the mirrorbow guys and ask you're
technical questions before ordering. I was impressed by the friendly
help I received.