Indian Head Test Pattern Question

[Murphyv310]

   

525/30i Aurora stored image viewed on scope some time ago (linearity issue was my error)

[peter scott]

Aha! Note the lack of graded dashes between the 325 and 575 legends and as Terry pointed out the lack of the RCA copyright label in the bottom right.

Peter

[Murphyv310]

Absolutely Peter.
I should redo this on my TV990 or on my Tec scope as its now repaired.

[peter scott]

I got myself into trouble trying to get the Indian Head pattern to fit in my Sony 9-90.
https://www.vintage-radio.net/forum/show...p?t=145807

My 9-90 had excessive width so the height had to be excessive too to get circles correct and the large circle was off the screen.



Peter

[Murphyv310]

Hi.
Actually the 9-90 had an external regulator pack for running of car battery which was an option of all things. Funny as all the caravan fraternity didn't seem to have one. I found this out when a 9-90 came in with this add on box when I worked with Sony. From what I remember it gave out 11.5v and was designed to regulate the supply from a running engine and to filter out noise that would give ripples on the picture.
I'm sure the HT is nominally less than 12v although the manual is marked with 12v, the Sony service manual does relate to it I'm sure.

[Refugee]

I spotted one of those Sony regulators in my box of bits a year or so ago. The output lead had been chopped off.
No idea if it would still work though.

[Murphyv310]

I'd imagine it would still work fine Ref. I've never opened one up so can't say if its a linear regulator or one of Sony's famous DC to DC converters.
https://www.vintage-radio.net/forum/show...p?t=119512

[Refugee]

If I see it again I will have a look.
If I remember rightly there was a TO3 visible inside with the case painted black or dark grey.

[Murphyv310]

Hi.
I've tried the pattern on my TV9-90 and the result is just as Peters, There is a tad too much width and the frame running at 60Hz the height comes up a little as well.
The pattern is from the Aurora 525/30i.
I have a load of good images stored on the PC so I should really get cracking on the PC and graphics card. Energy levels though need to come up a bit before I start, hopefully in a week or two.

[Terry]

Thanks Terry, I see what mean about the linotype style grey scale. There does appear to be quite few variants of this test pattern. I came across another bearing the RCA copyright mark and graded peaking verticals that has another actual grey scale indian but with less detail.

The original RCA card in post #7 is, as stated, as used in a monoscope whereas the RCA card in post #9 would have been for use as a slide or an actual card in front of a camera, so no need to resort to the linotype style dots and lines to produce the grey scale