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G8MNY  > TECHNI   08.07.22 11:15l 108 Lines 4782 Bytes #999 (0) @ GBR
BID : 25235_GB7CIP
Read: GUEST
Subj: BBC Testcard W
Path: IZ3LSV<IQ2LB<IQ5KG<IK1NHL<CX2SA<EA2RCF<LU9DCE<LU4ECL<VE2PKT<PI8CDR<
      GB7YEW<GB7COV<GB7CIP
Sent: 220708/0650Z @:GB7CIP.#32.GBR.EURO #:25235 [Caterham Surrey GBR]
From: G8MNY@GB7CIP.#32.GBR.EURO
To  : TECH@GBR

By G8MNY                                        (Updated Apr 13)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)

Thanks to Steve for the original bul...
For all you Techno phoebes looking at the Tech side of Freeview, here's a bit
more you can achieve with your Digital FTA box.
  ----- Original Message -----
  Subject: Hidden test card on Freeview
  1) Tune to BBCi on 200
  2) When BBCi background appears press Yellow, within 30 seconds
  3) Tune to another channel
  4) Go back to 200
  5) When BBCi background appears press Green, within 30 seconds
  6) The word secret should appear on the top right and then the Status
     page should appear.
  7) Enter 3, 3, 5, 8, 2, Red, Green, Yellow, Blue
  8) Wait between 30 seconds and a couple of minutes and TCW should appear 

  This does work on IDTV's as well, give it a shot, it only works on newer
  STB's apparently?
73 - Steve, G1KQH @ GB7COV
-----------------------------------------------------------------------------
The TESTCARD W, a 16:9 wide version of Testcard F & should look something like
this if you have compatible 8 bit ASCII Graphics font.
________________________________________________
ÛÛÛY²²²²²C²²²²²G±±±±±M±/\±±R°°°°°B°°°°°BLACK  ÛÛ  /|\
²ÚÄÄÂÄÄÂÄÄÒÄÄÂÄÄÂÄÄÂÄÄÒÁÁÒÄÄÂÄÄÂÄÄÂÄÄÒÄÄÂÄÄÂÄÄ¿Y   |
²³\\\__³__º__³__³__ÜÜÜÜÜÜÜÜÜÜ__³__³__º__³__///³²   |
²³~\\\ ³  º  ³  ³  ÛÛÜÜÜÜÜÜÛÛ  ³  ³  º  ³ ///~³C  575
±ÆÍÍØÍÍØÍÍÎÜÜØÍÍØÍ;.-Ä~~Ä-.ÔÍÍØÍÍØÍÍÎÍÍØÍÍØÍ͵² Lines
±³__³__³__ÞÛÛÝ__³_/'  _____ '\_³__³Ýݺ__³__³__³G of odd
±³  ³  ³  ³²²³  ³:   ³_³o³_³  :³  ³||º  ³  ³  ³± & Even
< >< ><ÌÄÄ´±±ÃÄÄ´    ³_³x³_³   ÃÄÄ´ººÇÄĹ>< >< > frame
°³__³__³__³°°³__³:   ³_³_³_³  :³__³±±º__³__³__³± lines
°³  ³  ³  ³..³  ³~\          /~³  ³²²º  ³  ³  ³R in the
°ÆÍÍØÍÍØÍÍÎÍÍØÍÍØÍ͸ú.____.úÕÍÍØÍÍØÍÍÎÍÍØÍÍØÍ͵°  full
±³_///_³__º__³__³__³__ºVVº__³__³__³__º__³_\\\_³B picture
±³///  ³  º  ³  ³BBC Widescreen³  ³  º  ³  \\\³    |
±ÀÄÄÁÄÄÁÄÄÐÄÄÁÄÄÁÄÄÄÄÄÄÂÂÄÄÄÄÄÄÁÄÄÁÄÄÐÄÄÁÄÄÁÄÄÙB   |
ÄÄÄGrey ramps pairsÄÄÄÄ\/ÄÄColour ramp pairsÄÄÛÛ  \|/
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
<---------52us of Picture area/line------------>

TESTCARD TESTS
SIZE/SHAPE/POSITION: On a properly set up 16:9 display, you should see a round
circle in the middle & the whole picture right up to the outer chevrons. On a
CRT you can adjust all of these, on LCD/Plasma they are designed in, & you
can't! Some position shift between RF, PAL, & RGB inputs is normal on displays.

DEFINITION: With a good RGB feed to your screen the highest of the 6 right hand
definition grating (720 pixels approx 7MHz?) should be displayed, but not if
your on a PAL only SCART port!
The lower frequency response (phase) can be assessed with the letter box at the
top, there should be no dragging of it's centre into the surround.

GREY SCALE: The 6 left hand grey scale steps should all look like equal
brightness steps, & no colour variation. The black & white ones include 2 dots
of a bit brighter & darker so that any peak clipping/cut off can be detected.
Different Gamma correction curves are needed for CRT & LCD per colour to
achieve the grey scale, but a Plasma display is quite linear.

CROSSHATCH: The white cross hatch lines ÄÅÄ are over the grey background are
for colour convergence & focus tests (CRT only). They include the clearer black
edged ÍÎÍ lines & corner diagonals as well.

COLOUR BARS: There are no castlations any more on the edges of the testcard
that used to show up Line timebase picture in syncs phase problems, but instead
there are colour bars (white yellow green magenta red blue black) & stripes to
show up early/late PAL/MPEG colour problems as well as PAL line pairing. Colour
tint & level is best judged on the skin colour of the little girl. On some
displays the colour satuation level varies depending on source..RF, PAL, RGB.

RAMPS: At the very bottom is a grey & colour dual pairs of ramps show up any
uneven steps in the MPEG encoding process/digital quantisation problems.

LIMITATIONS
On a small screen this Freeview Testcard W looks really good, but on a big one
you do see a lot of JPEG/MPEG line edge artifacts (ripples) which rather spoil
the quality.

There are no moving parts of this picture or any sound, so other aspects like a
lipsync test, independent of the variable camera-studio-tx sound/vision link
chain can't be tested.

From G0TEZ...
I thoght I would mention that, on Freeview,it is simpler now to get a testcard
(W).

Go to BBCi on 200.
Press Yellow.
Change to another channel and back.
Press Green.
Test card W will appear,

If not straight away, press G twice.

I have been doing this for a couple of years now. Before that, I used the
method outline by G8MNY as below.


Why Don't U send an interesting bul?

73 De John G8MNY @ GB7CIP



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