Rare find! A Magnavox Brittany tv!

[Yamamaya42]

AGC also works when adjusted.

the noisy picture is most likely due to the HV area not being enclosed yet, there WAS shielding on the original HV anode wire, not sure how much that mattered.

[Yamamaya42]

As mentioned, the HV cage is still all open, and is most likely spewing out RF interference, however when I got it, the top cover was missing and is most likely gone forever, so I have ordered a 11.5 x 11.5 Perforated Metal Sheet to try to shape a replacement, also a 80mm AC fan to place on top to keep the FBT cool, at first I was planning to replace / relocate the bleeder network ( candohm resistors), but so far it seems they are holding up very well, even after the -100 short, so I'm tempted to leave them for now and just keep em cool.

[kvflyer]

Originally Posted by Yamamaya42

As mentioned, the HV cage is still all open, and is most likely spewing out RF interference, ...

Could you temporarily fabricate a piece of aluminum foil into a "cage" to see if that stops the garbage? (Carefully, of course!)

[bandersen]

That really shouldn't be a problem. There are plenty of chassis that have a bare flyback on them. The HV cover is there to protect from HV not RF shielding. It's the RF type HV coils used in electrostatic sets that are a problem.

[Yamamaya42]

Well, LOOONG ago with my FADA, EM said about the same sort of thing,
" Is the HV cage cover, tube shields and any other factory shielding all properly in place as far as you can tell? Sometimes when a shield is missing it causes issues. "

The few tube shields are on, but the cage is still in pieces.
not sure where all the noise is from, but this WAS the first test, the twin lead on the tuner is crap, which will be replaced with a matching balun hooked direct to the tuner, and there is also 2 computers in the room just a few feet from the test setup.
over the next few days I hope to close the case and hook up the balun directly and hope to get better results, cause if the IF is out of alignment, it is really gonna suck as there is no instructions to do it.

[Electronic M]

Usually the factory shields matter. Depends on how good the engineers and bean counters were, and the standards of performance. There are cases where a tube or HV shield missing may not be noticeable and there are cases where it might be very noticeable. If you're chasing a noise issue it's a good idea to try to replace missing factory shields as a sanity check (even if you gotta wrap a tube in aluminum foil or put a soup or coffee can over something before spending too much time troubleshooting.
I've seen sets where lack of HV shielding wasn't noticable and sets where it is... usually but not always when lack of shielding is noticable there's some corona or mild arcing somewhere.

[Yamamaya42]

That's why I wonder about the original shielded anode wire, and if i will have to try to shield the new one somehow, perhaps with copper foil or something.

[Kevin Kuehn]

If the HV filters are good the anode lead will be no issue. From the video you posted it doesn't seem that snowy. It looks like low contrast, which could be from the room lights. It's possible it will get better when you use the intended CRT.

[Yamamaya42]

Originally Posted by Kevin Kuehn

If the HV filters are good the anode lead will be no issue. From the video you posted it doesn't seem that snowy. It looks like low contrast, which could be from the room lights. It's possible it will get better when you use the intended CRT.

The contrast got much better when I cranked up the AGC, almost too high, and yes, as before with the FADA, the 8YP4 does work, but not very well, the smearing will go away when I switch to the 16 inch tube.

[Yamamaya42]

This is the first TV this old type,(Roundie) that I have had with true AGC, and it's really temperamental, as in, it has a “sweet spot” too low and it washes out, too high, and it looses sync.
I'm guessing that this is normal behavior for this set.

[Yamamaya42]

And we have sound!

http://suzaku.live-evil.org/0424251901.mp4

And a LOT of buzz!

audio discriminator needs tweaking.

[old_coot88]

Just for the heck of it, roll the vertical and and see if that buzz changes pitch.

[Yamamaya42]

Originally Posted by old_coot88

Just for the heck of it, roll the vertical and and see if that buzz changes pitch.

No change,, its from the video itself. this set is like the RCA 630ts when it comes to sound, Split at the tuner, NOT a intercarrier set, at least the sound and video matches when tuned, just a lot of buzz

[Yamamaya42]

any attempted adjustment is gonna be a pain however.

http://suzaku.live-evil.org/maggie-sound.jpg
as T103 is one of those that has both top and bottom adjustments, the top is easy to get to, but not the one on the bottom without propping up the chassis and powering it up.

ONLY the sound discriminator should need tweaking, the IF 1/2 seems OK

[Kevin Kuehn]

Some sets had top slugs with a hole down through the center, so you could dip the alignment tool down through to engage the lower slug. Although this might be to early for that feature.