#31
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Aligning The Hickok 655
MY previous entry indicated the Hickok 655 is producing a marginally acceptable color bar pattern on both the 21CT55 and Sony. However the color bar waveforms indicate a total mess! The Hickok 655 has 19 pots and 6 switches that I "adjusted" by intuition. What is needed is the official Hickok 655 initial setup procedure. Surly this document must exist somewhere possible included in the instruction manual or in some member's memory? Anyone attempting a precise alignment of the two wideband RCA CTC2 CTC100 and CTC2B 21CT55 must be aware that precise setup of the color matrix requires a bar generator having both Q and I bars for the CT100 and both Q and B-Y bars for the 21CT55! Both RCA and SAMS procedures insist on using bar generators that provide 100% saturated R-Y, B-Y, "Q" and "I" video signals. The RCA WR-61A and the Hickok 600 series would be exceptable.
So, any suggestions how I can obtain this information would be appreciated. |
#32
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I have no information, but from what those control labels say I'd bet I could set it up properly using a scope on the output and some references to the NTSC standards for what the levels should be for R, G, and B.
From the schematic posted by John Folsom, it appears the phase is set by fixed components in a synthetic delay line (upper right). Unfortunately, the schematic is too fuzzy to read the values, so it might have something to do with the adjustable LC's at the bottom also. Anyway, it seems you would look at the red, green, and blue bars and adjust the corresponding "Y Gain" for the correct luma level, and the corresponding "Bar Sat" for the correct chroma level. I think this would fix the primary and secondary color bars. The overall chroma gain sounds like it affects subcarrier on both color bars and I/Q/ whatever, so maybe you would need to adjust it first. If it affects burst level, you would adjust it for that, and then adjust the R, G, B controls. |
#33
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Hickok 655 much improved
Hi Wayne.............Thanks for your reply. I was hoping for some Hickok 655 official alignment procedure would some how show up, wishfull thinking I guess. Surely with 29+ pots available on the top control panel, Hickok had to have an alignment procedure for the poor tech that had to use this analog monster?
Anyway the approach you suggested made sense to me after I realized the RGB "BAR SAT" pots were chrominance settings and the RGB "BAR GAIN" pots were luminance settings! I then rearranged the early RCA color bar order to the strange Hickok color bar order and everything started to come together. |
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