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Old 02-25-2008, 05:17 PM
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Tomcomm Tomcomm is offline
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RCA CTC2B Peaking Coils

My 21CT55 with 21FBP22A is now fully operational as an external composite video monitor. Convergence is acceptable, and the color is quite vivid and bright. I can switch the input between DVD and C-Band NTSC or 4DTV satellite with no correction of contrast, brightness, hue and chroma required.

Only real problem is in the video amp response. There's a lack of fine detail and lots of ringing present in the picture. I strongly suspect the numerous video peaking coils I had to replace that were open. I used approximate equal value generic coils which have iron or ferrite cores with low Self-Resonance-Frequency. All of the original RCA coils were multi-section universal pi winding on phenolic cores which had a higher SRF and bigger physical size. I very much would like to get a set of original RCA OEM or at least the same non-iron coil configuration as the original RCAs.

Bourns-Miller seem to have the most promising selection, but indicate they only have a few values inventoried at Mouser Electronics. Do any of you guys have access to these obsolete coils? Any leads will be greatly appreciated......Tom
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Old 02-25-2008, 09:09 PM
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old_tv_nut old_tv_nut is offline
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Do you have the details on what the inductances and self-resonant frequencies should be, and what you actually have?

If you want to experiment, here are some ideas:
If you can't get or wind the proper coils yourself, you might be able to get higher SRF by using 2 coils of half the inductance in series, or some such arrangement. Also, if the SRF is close but you still see ringing, you might try damping the self resonance by putting some large resistance across the coil.
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