Grant wrote:

On Sun, 08 Aug 2010 16:08:50 -0400, "Michael A. Terrell" wrote:


N_Cook wrote:

Geoffrey S. Mendelson wrote in message
...
N_Cook wrote:
Got a few no-name URCs from UK Poundland "pound shop" , badged as
Signalex ,
81415, 10 in 1 . 1 GBP for all the functionality of a URC. This type you
can
set it to flicker away to itself until it reaches the end of a batch of
codes.
Removed the 3.58MHz resonator (why so apparently accurate?) .

That's the NTSC color carrier frequency. Not only were they made in the
billions over the years (every US/Canada/Japan, etc) color TV had one,
so did every VCR, and lots of other things.

I'm sure they will still be around for a while because while digital TV
has taken over in the US, it has not in the entire world and anything with
a composite video input or output needs one.

They became the defacto standard for things like telephone dialers,
and many things that needed about a 4mHz crystal because they were so
cheap
and plentyful.

One of the famous "blue boxes" (telephone hacking devices) was made by
taking a Radio Shack tone dialer and replacing the 1mHz crystal with a
3.58mHz one.


With 1.5V
pk-pk locked in with receiver over range 2.7 to 5.1M, and again about
300K
to 11M would operate using 1.5V. So far have only used with original
3.58M ,
6M and 7.5M sine inputs. Am I serendipitously likely to get a hit
somewhere, at least the unit on/off model recognition code if not
function
code plus the model code

So 2 out of 2 of these URC have been amenable to this mod but no match
to
the unit in question found so far. Is there any general guidelines for
makers to choose certain types/ranges of coding for different types of
equipment or is it totally open for them to choose? Assorted bits of kit
show at least partial responses to some of these off-spec codes, but not
my
target one so far.

Look up LIRC (Linux Ifrared Remote Control). There is a library of remote
codes, a way of capturing new ones from a remote and since the definitions
are in a text file, they are easy to "hack".

There are all sorts of input and output devices, if you have a PC with a
regular serial port (not USB), you can build a transmitter from the proper
plug, a resistor and an IR LED.

Geoff.


--
Geoffrey S. Mendelson N3OWJ/4X1GM
To help restaurants, as part of the "stimulus package", everyone must
order
dessert. As part of the socialized health plan, you are forbidden to eat
it. :-)

I was not aware of that frequency as being significant , the equivalent over
here is millions of 4.433619MHz and x2 of that , quartz crystals for Phase
Alternate Line. That would explain why it was Never The Same Color (twice)
if they could get away with using ceramic resonators rather than quartz.


Sigh. The ceramic resonators were used as a chroma trap. Quartz
crystals were used for the color reference. As far as 'Never The Same
Color', network programing was carried across the US on buried coaxial
cables or by microwave relays. Unlike tiny European countries, we
couldn't broadcast from a singe site. Because of this, they were video
amplifiers and equalizers spaced at regular intervals. Because it was
mostly tube, and there were thousands of them in each network they
required constant maintenance. When the network switched to a different
feed from a different studio, there was a phase difference. temperature
changes on the coax caused it's properties to change, as well. That was
why VIR and VITS were developed. It allowed for automatic equalization
to compensate for temperature changes, or when a signal had to be
rerouted. There were a lot of redundant paths, to allow for equipment
failures, or live remote feeds in the days before STL equipment. The
flexibility of the system was proven when Bell Telephone technicians
tied every TV station in the country together in a couple hours, to

allow full, live coverage of the assignation of President Kennedy. I
I thought he kept them secret? --'^^^^^^^^^^^ Freudian slip?

Wonderful what slips a careless spellcheck will show


Laugh all you want. My eyesight is very poor.