went ahead and installed the new focus coil, improvement, will play with it some more. Have another focus coil to try later. The problem is these are alternate PN coils so I want to try them both and see which works the best.

got the new focus coil in it. maybe better but still I think its a bit under scanning. The focus coil seemed to help a bit with the cathode current on the HOT and "maybe" the scan.

I have a new yoke (the triad) but am just a bit burned out on this one. the pic looks real nice, color wise. The focus seems a touch soft (I have the focus coil slug all the way in, it effects the focus but does not seem to peak).

I did replace the focus rectifier just in case, no change. Overall the pic is very very good, and I am tired of fooling with it.

I double checked the filter caps, they test like new so I will leave them be.

I did add the B+ fuse a 750ma (normal current is about 450-500ma) so if the filters ever do short out the tranny will not have to wait for the main circuit breaker. the fuse is in one of those in line jobes, properly strain reliefed of course. The HOT cathode fuse is a micro fuse that has a neat holed soldered directly to the jumper term strip, mounted on top of the chassis, VERY easy to pop the fuse and check the current. I soldered in a .1uf cap across the fuse holder so you dont even have to bypass when checking. I thas a 310ma fuse, cathode current is right around 220-240 depending on beam current.

I still plan to buile a plenum to fit in the cage and direct air from two micro fans (the kind on cpu's). I need two as they dont move much air. The plenum will be made from cardboard and will direct the air to the main body of the fly. the intake will come from the back side of the fly, the cage door left open. the exit will be from the existing convection louvers. The fans run off
12vdc, I will prob just power them from a wallywart transformer. I am not going to do anything that cant be undone and returned to the stock configuration.

watching Kojak on it now :thmbsp:

Run your 12vdc PC fans on 5 volts. They will slow down and be quiet while still keeping the fly cool. Most PCs vary the voltage depending on heat load so they dont sound like a jet all the time.

You could also use the rectify and filter the 6 volt filament supply for the fans.

still not satisfied.

I chaged the pic format, so there would be a margin all around the pic (cant recall which format but it was on the convert box).

in this smaller format I could see the pic was clearly not centered, so I centered with the horz centering pot.

switched back and now I have the dark bar on the extreme left edge.

Now the Raster is fine (full screen) its just the pic that causes the dark vert bar on the left.

I did some more reading and I am back to looking at blanking. There is a triode section of a 6GH8 that takes a pulse a the grid, and is coupled from the plate to the cathode of the chorma driver tubes.

IF for some reason the tubes were cut off too long I assume this is what it would look like.

But there is just not a lot of parts involved, so I will be checking them AGAIN and doing some tube rolling.

I guess I could compare the CRT grid voltages to the composits video signal on my dual trace scope and see if they line up.

I threw my net over on ARF and fun with tubes to see if any one else has some input on this dog.

Just for fun I am going to try the one OTA transmission on UHF and see how it looks. the problem is its such a weak station that the pic is awful.

I am just try to eliminate the converter box as an issue (it works fine on other tv's).