This post is about a very easy fix for what i believe can be a very common issue with imported FM-Towns monitor. There is not much English information on the net regarding Japanese FM-Towns computers, even less about the monitors. I have read some reports of folks getting monitors imported from Japan and receiving them non functional. Happens I very recently Imported one myself and of course... It did not work. So I open the thing up, very easy as there are only 4 screws holding the main cover, and was shocked by what i saw. There is a RF shielded PCB connected directly to the electron gun through a 10 pins round connector and that connector is pretty much the only thing to hold down that rather bulky PCB in place. There was some traces of silicone like glue that seemed to have the double role of sealing the connector part of the electron gun and helping to secure the PCB in place. The amount of glue however is very small and does not really help securing that PCB if you ask me, especially after 20 years when that glue gets brittle. So the PCB in my monitor was just dangling there almost completely disconnected and holding by a hair. Obviously the "hardship" of international shipping is to blame as the monitor was supposed to be in good condition when i got it shipped. Furthermore, the pins on the electron gun part of the connector are not very strong and get bended easily, this picture was taken right after i opened the monitor and put aside the PCB, revealing the damaged connector with crooked teeth. Now, whenever you are working with CRTs always be careful not to get zapped as some capacitors could be holding high voltage. The connector pins are easily bended and they can be straightened easily with a small flat head screw driver. Here is what my connector was looking like once i refurbished it. And here's the corresponding female part on the PCB, notice that it is keyed so no risk of connecting it wrong. The PCB should fit quite smugly and the connection is tight enough for it to hold itself through careful handling. It is safe to test the monitor. However this connection is not safe in the long run, any kind of rough handling or simply shipping it in the mail will likely get that PCB disconnected again. I considered gluing the thing but i realized this PCB likely needs to be disconnected during servicing or while troubleshooting more serious issues, in that regard gluing it is not convenient . I always try to think for long term maintenance. So i had an idea, I used light duty glue to fix pieces of cork on the back of the RF shielded PCB. The idea is that the plastic cover of the monitor presses gently on the corks and prevents the thing from getting disconnected whenever the cover is on. I took measurements and 2 Cm is about the thickness you need. Happens this was pretty much exactly equal to half of a wine bottle cork. (talk about Murphy's law working on your side for a change) So here's what is looks like ( sry for blurry picture): I then put back the plastic cover and verified with a flashlight that the cork was making contact with the cover and the pressure exerted seemed just right. Now for me this was a very easy repair but it had never been documented before as far as i know and this is likely to be a VERY common issue with these monitor, a weak point in the engineering of them, considering how usually CRTs are tanks. Here some screenies of my monitor working after i fixed it:
