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Naomi CRT Swap issue
AstroFan:
Have you tried putting magnetic rings from another yoke/tube or restoring the original magnetized sleeve yet?
ID4:
--- Quote from: AstroFan on June 06, 2022, 01:17:38 pm ---Have you tried putting magnetic rings from another yoke/tube or restoring the original magnetized sleeve yet?
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Hi!
If I can't demagnetize it, I plan to try putting magnetic rings form another tube, and then adjust it.
Thanks!
ID4
ID4:
Hi!
I have a Sanwa 29es31 chassis on hand
Is this chassis compatible with the original Naomi/Nano tube/yoke (Toshiba A68KSM696X)?
Remember that I am using the A68KSM696X yoke with the philips tube.
Thanks!
ID4
lilshawn:
you need a special meter called an LCR meter to properly measure the horizontal and vertical yoke windings and see if they are close enough to the original.
your horizontal inductance should be within about ~0.05 uH and the vertical within ~0.3 uH without having to change anything and your regular screen controls can make up for the difference... otherwise you are looking at changing tuning the capacitors in the horizontal to try and make up for it. any further than ~0.15 uH on the horizontal and ~1uH on the vertical from the original, will likely blow up the chassis when powered on.
you can KIND OF measure it with an ohm meter to find out if it's close, but your really need to find out what the natural oscillation frequency of the coils are otherwise they yoke will fight the current being put out by the chassis and run really hot... or just plain blow up when you first power it on.
the yoke is essentially a coil of wire that has a natural flow of current in and out and does not create resistance. if operated outside of this natural flow in and out, the coil resists the change and becomes a blockage in the circuit. other parts of the circuit relying on this current flowing through unrestricted will fail.
ID4:
Hi!
Ok I know how to measure ohms and inductance of yokes, I have done it before.
The Toshiba yoke LH is around 0,20 that meets the nanao chassis.
The sanwa chassis is compatible with the toshiba A68KSM696X, as described in the service manual.
Toshiba (A68KSM696X):
Lh 0.196mh
Lv 13.8mh
Rh 0.6 ohms
Rv 6.9 ohms
I have another philips tube (A68ESF002X43):
Lh 0,309 mh
Lv 5,2 mh
Rh 0.340 ohms
Rv 4,680 ohms
Remember that I'm using a philips tube (A68ESF002X11) with the Toshiba original yoke (A68KSM696X)
If I hypothetically use directly the A68ESF002X43 philips tube including his original yoke, with the nanao or the sanwa chassis, I would have to modify the chassis to make it compatible with the philips yoke's Lv 5,2 mh, in that case what capacitos need to be changed? and what values?
Thanks!
ID4
--- Quote from: lilshawn on June 28, 2022, 11:14:49 am ---you need a special meter called an LCR meter to properly measure the horizontal and vertical yoke windings and see if they are close enough to the original.
your horizontal inductance should be within about ~0.05 uH and the vertical within ~0.3 uH without having to change anything and your regular screen controls can make up for the difference... otherwise you are looking at changing tuning the capacitors in the horizontal to try and make up for it. any further than ~0.15 uH on the horizontal and ~1uH on the vertical from the original, will likely blow up the chassis when powered on.
you can KIND OF measure it with an ohm meter to find out if it's close, but your really need to find out what the natural oscillation frequency of the coils are otherwise they yoke will fight the current being put out by the chassis and run really hot... or just plain blow up when you first power it on.
the yoke is essentially a coil of wire that has a natural flow of current in and out and does not create resistance. if operated outside of this natural flow in and out, the coil resists the change and becomes a blockage in the circuit. other parts of the circuit relying on this current flowing through unrestricted will fail.
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