Very interesting, still have my AWSD Samsung tube tucked away for a rainy day.
Not sure if its any help, but at least this Iyama manual has a schematic using the 1888FTC and its pinout, etc...on page 73 I think. It might be of some use to compare with the datasheet you found.
https://mega.nz/file/Pg0z1axC#O3GlQcMHgGJnkE8Nl2tQXNbAyzu-EdQagwKRvGwQEzs
If I get a chance, I will read though this. I used ot be able to tell ya how what every component in crt monitors were for and ho they operated, etc...I could have at one point drawn you an schematic so you could out together a working monitor, but alas, no more
It will take some time for it all to come back to me.
Not sure if its any help, but at least this Iyama manual has a schematic using the 1888FTC and its pinout, etc...on page 73 I think. It might be of some use to compare with the datasheet you found.
https://mega.nz/file/Pg0z1axC#O3GlQcMHgGJnkE8Nl2tQXNbAyzu-EdQagwKRvGwQEzs
If I get a chance, I will read though this. I used ot be able to tell ya how what every component in crt monitors were for and ho they operated, etc...I could have at one point drawn you an schematic so you could out together a working monitor, but alas, no more
That helps out tremendously. Not only does it show the pinout of the chip, but also shows how they leveraged the horizontal and vertical deflection outputs to drive their dynamic focus circuit.
Page 26 has a whole description of the Dynamic Beam Focus (DBF) circuit and example waveforms. They show the feedback from the horizontal deflection alone as well as the synthesized signal you get from combining both the vertical and horizontal feedback into your DBF circuit.
Currently, the Toshiba only brings in the Horizontal Deflection to its DBF circuit. I would like to also bring in the vertical deflection feedback and drive the dynamic focus pin on the Toshiba with a similar synthesized signal as described in the PDF. I have example waveforms and should in theory only need to construct the small vertical section and connect it to the existing dynamic focus transformer already on the Toshiba. This would further improve the DBF function and hopefully provide more corner focus correction in addition to the edge focus correction already in place.
I saw that
was just waiting for ya to take a look, it is a nice service manual. If only companies today would do the same with their products, but they dont want you to repair stuff, just throw it away and get a new thing.
jimmyjames
Professional
Those cap kits change when talking about the Matsu monitor I think. I have to get a spare chassis for my Matsu soon so I’ll have to relook it up. I think I saw something on arcade otaku about it. I love my Matsu monitor. I thought it had to be a PF until I took the cover of the back and was like wtf. My NNC was built in 2007 and has very little use. However I like backups in case something goes wrong.
GeekMan1222
Grand Master
This is correct there's a couple of cap values that change if the tube is Matsushita or Toshiba.
Its something to keep an eye out for when swapping chassis's too but I cant remember if its actually a mission critical thing though. Like if the value is is different it wont be like game over for the tube.
Obviously you would want to keep as close to factory spec though.
Seems like a great option to replace the time bomb weiyas. Any pics of this running on awsd tube? ive heard good things about the pf and wondering if it translates over to the samsung tube with this mod.
chacal231077
Grand Master
Hi! 
Can't wait to be able to program my corrupt TMP87CM38N-5NF5 bios
which no longer remembers all the screen settings.
If I remove the Toshiba Remote in Extended Menu mode, all the settings collapse into nothingness.
image in a dark circle, deep black, hieroglyph as screen language
Can't wait to be able to program my corrupt TMP87CM38N-5NF5 bios
which no longer remembers all the screen settings.If I remove the Toshiba Remote in Extended Menu mode, all the settings collapse into nothingness.
image in a dark circle, deep black, hieroglyph as screen language
Any ideas what to change on pb9929 chassis to get full horizontal size?
My friend swapped A68LTF356X tube from Toshiba hd crt without yoke replacement and can’t adjust horizontal size to full screen. Except horizontal size everithing is OK.
Thanks
My friend swapped A68LTF356X tube from Toshiba hd crt without yoke replacement and can’t adjust horizontal size to full screen. Except horizontal size everithing is OK.
Thanks
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GeekMan1222
Grand Master
I been meaning to document all the inductor values in full for these chassis's at some point
I highly recommend anyone with one of the Tosh PF D29 variant chassis's to check the larger inductors to see if the glue is failing and they are coming loose at all. I seen it happen about 4 times now where the inductor breaks off its mount it can rip the copper wire off the winding, if your really unlucky it rips on the inner part of the winding requiring you to unwind the entire coil and rewind it to solder it back. So do your self a favor and check it if you plan on moving the cab alot.
Use some hotglue super glue or something to secure it back to the plastic base, if the coil is out of circuit it can cause alot of issues on the chassis causing a failure, one of the inductors near the flyback if that comes loose causes a higher wattage resistor in series with it to go thermonuclear and glow red hot.
JohnRambo'sKnife
Champion
Follow up question - I believe the above picture is of the PD1843. For the PB9929, where is this resistor located? R318 on the PB9929 measures 1.0 ohm, but I just want to confirm as I am not technical on CRTs.Modifications
To use a Toshiba PF in an Egret 3 or AWSD without doing a tube swap, you will need to perform the 3 modifications below. This will prep the chassis to be compatible with the tube. If you want a plug and play solution, you will also need to adapt from the 1.55mm pin headers on the Toshiba PF chassis to the 2.36mm pin sockets that the DY connectors and degauss connectors on the tube. Don't forget the JST connector for the earth ground on the neck board and the power connector.
1. Vertical Deflection
If using a vertical deflection yoke with a lower impedance (~ 8mH), you might notice that you can not get the picture to stretch to fill the screen vertically. This is likely due to the current limiting resistor (R323). You can slightly lower the resistance of R323 and get more vertical picture size when using a lower impedance yoke (or a yoke that just needs a larger A.p.p)
I have found that using a 0.750 ohm resistor in place of the 1.0 ohm at R323 - I can successfully fill the vertical screen when using a lower impedance yoke around ~7-8mH
R323 shown below (Already changed to a 0.750 Ohm)
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Touki_JAFF
Beginner
Hello @THCsoftcore ,
Yes, on my PB9929 chassis, it is the R318.
I paired my PB9929 with a Samsung A68QCP993X506 :
- Single Focus
- lh ~ 330uH ~0.80ohm
- lv ~ 7.3 mH ~ 5.60 ohm
I changed it and was able to stretch the image to fill the screen.
Yes, on my PB9929 chassis, it is the R318.
I paired my PB9929 with a Samsung A68QCP993X506 :
- Single Focus
- lh ~ 330uH ~0.80ohm
- lv ~ 7.3 mH ~ 5.60 ohm
I changed it and was able to stretch the image to fill the screen.
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JohnRambo'sKnife
Champion
Does anyone know the connector type for the neckboard ground wire used on the Toshiba PF? It is the white locking connector that connectors the tube wire ground to the neckboard. I believe if is a JST HXH type, but would be great if someone could confirm.
Some of you may have seen my wei-ya troubleshooting thread and have seen that I swapped to the modded PF chassis to get it working while I set the wei-ya aside for troubleshooting.
Anyway, I get a clear picture but the image is very dark.
I measured heater voltage and it fluctuates slightly around 5.67V before stabilizing around 5.7V, which is quite a bit lower than the 6.3V spec, and I was under the impression that both high and low heater voltage are bad for the tube.This is with the 1.3ohm heater resistor.
Rather than just adjusting screen to try to compensate, I'd rather get everything set up correctly.
I read somewhere that measuring heater voltage accurately is difficult, but hearing what others are getting would help to tell me if something is wrong with my setup.
Can anybody else that has done the mods measure their heater voltage and report back?
Edit: Also, can I run the PF chassis off of 120VAC? I've been using a stepdown but it would be nice to be able to not have to.
Anyway, I get a clear picture but the image is very dark.
I measured heater voltage and it fluctuates slightly around 5.67V before stabilizing around 5.7V, which is quite a bit lower than the 6.3V spec, and I was under the impression that both high and low heater voltage are bad for the tube.This is with the 1.3ohm heater resistor.
Rather than just adjusting screen to try to compensate, I'd rather get everything set up correctly.
I read somewhere that measuring heater voltage accurately is difficult, but hearing what others are getting would help to tell me if something is wrong with my setup.
Can anybody else that has done the mods measure their heater voltage and report back?
Edit: Also, can I run the PF chassis off of 120VAC? I've been using a stepdown but it would be nice to be able to not have to.
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