Update on SPDIF to analogue

On Fri, 30 Nov 2012 09:25:06 -0000, "Rick" wrote:

I had read a couple of comments from people reviewing a different unit
saying that they just got cracking on Freeview HD channels, but maybe it was
the way they had their TV setup, with the menu in my TV set to 'PCM' the
device outputs stereo from the HD channels perfectly, it doesn't work when
set to 'Dolby digital'.

Right, so on 'PCM' you're able to decode Dolby from the stereo output
of that unit and get the 5.1?

"Grimly Curmudgeon" wrote in message
...
On Fri, 30 Nov 2012 09:25:06 -0000, "Rick" wrote:

I had read a couple of comments from people reviewing a different unit
saying that they just got cracking on Freeview HD channels, but maybe it
was
the way they had their TV setup, with the menu in my TV set to 'PCM' the
device outputs stereo from the HD channels perfectly, it doesn't work when
set to 'Dolby digital'.

Right, so on 'PCM' you're able to decode Dolby from the stereo output
of that unit and get the 5.1?


As far as I'm aware no, it's just a appears to be a straightforward digital
optical or coax to analogue L R stereo converter, however if it's of any
help I've scanned the instructions that came with it and put them up on
Dropbox.

http://dl.dropbox.com/u/11815200/78409_0002%20(1195%20x%201402).jpg

In article , Rick wrote:


"Grimly Curmudgeon" wrote in message
...
On Fri, 30 Nov 2012 09:25:06 -0000, "Rick" wrote:

I had read a couple of comments from people reviewing a different unit
saying that they just got cracking on Freeview HD channels, but maybe
it was the way they had their TV setup, with the menu in my TV set to
'PCM' the device outputs stereo from the HD channels perfectly, it
doesn't work when set to 'Dolby digital'.

Right, so on 'PCM' you're able to decode Dolby from the stereo output
of that unit and get the 5.1?


As far as I'm aware no, it's just a appears to be a straightforward
digital optical or coax to analogue L R stereo converter, however if
it's of any help I've scanned the instructions that came with it and
put them up on Dropbox.

My experience is that makers use 'PCM' or 'LPCM' to mean 'sdpif format
stereo'. Never seen an example of them using the label for surround
(ignoring the 'trick' surround-via-stereo methods). Instead they seem to
use other terms like 'bitstream' or 'surround' for 2 channel.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Jim Lesurf" wrote in message
...
In article , Rick wrote:


"Grimly Curmudgeon" wrote in message
...
On Fri, 30 Nov 2012 09:25:06 -0000, "Rick" wrote:

I had read a couple of comments from people reviewing a different unit
saying that they just got cracking on Freeview HD channels, but maybe
it was the way they had their TV setup, with the menu in my TV set to
'PCM' the device outputs stereo from the HD channels perfectly, it
doesn't work when set to 'Dolby digital'.

Right, so on 'PCM' you're able to decode Dolby from the stereo output
of that unit and get the 5.1?


As far as I'm aware no, it just appears to be a straightforward
digital optical or coax to analogue L R stereo converter, however if
it's of any help I've scanned the instructions that came with it and
put them up on Dropbox.

My experience is that makers use 'PCM' or 'LPCM' to mean 'sdpif format
stereo'. Never seen an example of them using the label for surround
(ignoring the 'trick' surround-via-stereo methods). Instead they seem to
use other terms like 'bitstream' or 'surround' for 2 channel.



Thanks for that info Jim, whilst I'm here, that little Lindy unit comes with
a 5v 500mA wall wart power supply, although if I could I'd rather have it
powered from a spare USB socket on the TV and was wondering about knocking
up a lead [according Wicki, USB voltage output should deliver from 500–900
mA (general)] so is it wise to assume that the TV's USB sockets will
comfortably deliver sufficient current? as unsurprisingly that kind of spec
isn't given in the manual.

In article , Rick wrote:


...whilst I'm here, that little Lindy unit comes with a 5v 500mA wall
wart power supply, although if I could I'd rather have it powered from a
spare USB socket on the TV and was wondering about knocking up a lead
[according Wicki, USB voltage output should deliver from 500"900 mA
(general)] so is it wise to assume that the TV's USB sockets will
comfortably deliver sufficient current? as unsurprisingly that kind of
spec isn't given in the manual.

Others may give different opinions, but FWIW...

I'd be cautious of assuming a USB socket on something like a TV can
reliably supply 500mA - even if they claimed it. I've never had a TV with a
USB socket. But I've had other devices that failed to supply more than
about 100mA via USB. In some cases "it works"... until at some later time
it fails. Had more than one mains-powered USB hub like this! Some seem to
have the equivalent of a thin section of track on the board as a 'fuse'. So
once blown, that port is dead.

That said, it might work and be fine for all I know. But it might booger
the port. Its a bit like testing matches... :-)

FWIW in general with a computer I tend to use a mains-powered hub for all
USB devices that don't have their own PSU. Rather lose an external port hub
than one inside the actual computer. But I am an old fogey about such
matters.

Ideally, I'd suggest testing the device with a current meter or a bench PSU
with meters. That's what I do here. But these aren't things most people
will have. However it may be that the device doesn't actually need anything
like 500mA despite what is printed on the wall wart.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Rick wrote:

that little Lindy unit comes with
a 5v 500mA wall wart power supply, although if I could I'd rather have it
powered from a spare USB socket on the TV and was wondering about knocking
up a lead [according Wicki, USB voltage output should deliver from 500–900
mA (general)] so is it wise to assume that the TV's USB sockets will
comfortably deliver sufficient current? as unsurprisingly that kind of spec
isn't given in the manual.

USB power is a bit of a moveable feast, originally devices were only
allowed 100mA until they asked nicely for more power, the maximum being
500mA, some USB ports will shutdown if more power is taken than they
have agreed to give.

Many newer devices charge via USB and need more than 2.5W, so dedicated
5W and 10W chargers exist, the sensing tends to be via different value
resistors across the USB bus, rather than active communication between
the devices.

USB3 will allow (but not require) up to 100W.

If you're lucky you'll get away with it.

"Jim Lesurf" wrote in message
...
In article , Rick wrote:


Ideally, I'd suggest testing the device with a current meter or a bench
PSU
with meters.



Thanks Jim, nothing on the unit to say how much current it draws, other than
to 'use with the 5 V power unit supplied', Ill devise a little male/female
plug and socket breakout arrangement so that I can check the current
consumption.

"Andy Burns" wrote in message
o.uk...
Rick wrote:

that little Lindy unit comes with
a 5v 500mA wall wart power supply, although if I could I'd rather have it
powered from a spare USB socket on the TV and was wondering about
knocking
up a lead [according Wicki, USB voltage output should deliver from
500–900
mA (general)] so is it wise to assume that the TV's USB sockets will
comfortably deliver sufficient current? as unsurprisingly that kind of
spec
isn't given in the manual.

USB power is a bit of a moveable feast, originally devices were only
allowed 100mA until they asked nicely for more power, the maximum being
500mA, some USB ports will shutdown if more power is taken than they have
agreed to give.

Many newer devices charge via USB and need more than 2.5W, so dedicated 5W
and 10W chargers exist, the sensing tends to be via different value
resistors across the USB bus, rather than active communication between the
devices.

USB3 will allow (but not require) up to 100W.

If you're lucky you'll get away with it.


Even if I don't, the telly has a five year warranty anyway :-) I also have
small separate computer speakers rated at 12 V - 0.5 amp, fed from a
transformer type wallwart, I'm wondering whether I should/could use my
computer's internal power supply to power them as well, mainly from the
point of view of tidiness and a reduction in power consumption.

I appreciate it depends on how much the computer has to handle, however it's
not unduly stretched, the usual sort of thing dual core processor, 8 GB ram,
sata C and D drives supplied by a 350W power supply, spec here.

http://dl.dropbox.com/u/11815200/PS%20(974%20x%20531).jpg

On 01/12/2012 16:26, Rick wrote:


snip
Thanks for that info Jim, whilst I'm here, that little
Lindy unit comes with a 5v 500mA wall wart power
supply, although if I could I'd rather have it powered
from a spare USB socket on the TV and was wondering
about knocking up a lead [according Wicki, USB voltage
output should deliver from 500–900 mA (general)] so is
it wise to assume that the TV's USB sockets will
comfortably deliver sufficient current? as
unsurprisingly that kind of spec isn't given in the
manual.

My Samsung TV displays a warning message if USB power
exceeds the port limit. One of its two USB ports has
a higher rating than the other = intended for a disc
drive rather than a wireless dongle.

"Jim" wrote in message
...
On 01/12/2012 16:26, Rick wrote:


snip
Thanks for that info Jim, whilst I'm here, that little
Lindy unit comes with a 5v 500mA wall wart power
supply, although if I could I'd rather have it powered
from a spare USB socket on the TV and was wondering
about knocking up a lead [according Wicki, USB voltage
output should deliver from 500–900 mA (general)] so is
it wise to assume that the TV's USB sockets will
comfortably deliver sufficient current? as
unsurprisingly that kind of spec isn't given in the
manual.

My Samsung TV displays a warning message if USB power exceeds the port
limit. One of its two USB ports has a higher rating than the other =
intended for a disc drive rather than a wireless dongle.


Thanks for the info, I can give it a try and see what happens, the Samsung
UE32ES5500 has two USB ports and I'm using one to run a SSD to record
programmes, a downside I've discovered is that they use Sony .srf files,
which I haven't yet found a way of playing and converting to other formats
on my computer, as I can with the .trp files that are used on my Technomate
HD satellite receiver.