Just got this magnavox

[DaveWM]

still checking it over, seems the voltages are all wrong but it works fine.

one really odd thing is the current reading on the B+ out of the doubler, only reading 24ma not 280ma per the schematic. No way the 24ma can be right its got a dozen tubes!

I am going to have to triple check my meter settiing on that. I have scoped a few of the check points in the problem area (vert sweep) scope patters look ok but low peak to peak. But then again the pictrue is fine so I am about ready to call it a day and leave it alone before I break something.

[DaveWM]

what a dope, the DMM range was wrong, changed it to amps, got .250 so current is right.

Still need a new linearity trim pot (super critical adj, its all junked up, way beyond deoxit). The problem is its 600 ohm and I think hi wattage (maybe a wire wound pot).

I am hitting the local surplus store to see what they have, then my vintage radio guy this weekend.

Pictrue is fine, just very very sensitive to adj (or vibration as in moving it around), which is why I want a more reliable pot.

Still need to pull the am/fm tuner amp and check it out.

[DaveWM]

got the pic working fine now, a new linearity pot and all it working well now. I had to fugde the series resistor value since the only trim pot I could find was a 300 ohm, so I upped the series resistor value and wattage, and got it right in the middle of the adj, bonus is with the lower value trim pot the adj is less critical (just hope the range does not shift too much).

I recapped the astro sonic tuner amp that goes with the TV for sound. had a persistant rushing sound that was still in one channel after the recap.

Turned out to be a leaky transistor in the preamp circuit. replaced it with a generic silcon transistor, sounds great now.

Still have the filter cans to do on both the astro sonic amp, and the TV chassis, and still have to pull the TV tuner and clean it up (dirty contacts).

but getting close now.

[zenithfan1]

Sounds like she's going well, lets see some pics of 'er running.

[DaveWM]

looks like a battlefield right now, parts all over the place

hope to pull it all back together soon. I don't want to reinstall that darn tuner till I know it is ok.

I am going to put the two FM stereo to the test, put a 400hz sine wave to it thru a stereo transmitter.

something still odd going on.. one channel distorts when the adj trim pot is turned up much more than 1/4 the other channel is fine all the way up, just louder like it is supposed to be.

The scope will prove out where the distortion is happening. I can live with it as is (just adj the two trim pot to no more the 1/4 and all is fine, lisening level is correct as well), but I want to know why it is doing this.

After this experience I hope to tackle more TV's smaller TV's this thing is HUGE...

[zenithfan1]

I had a Maggie stereo do that to me once, never tried to fix it, just dropped it back off at GW. I wish I had it back sort of. Good luck and I hope you get everything back together with no bad issues. (there's always little ones )

[DaveWM]

if anyone cares about the SS amp used in this TV I have a thread going on in the vintage solid state detailing the issues I am having with the astrosonic unit used for the audio of this set.

[Charlie]

I have the same set, but with slightly different sliding doors. This one is non-remote. I haven't done anything to it yet. It plays, but recently the filters took a dump. Made a really good picture before that happened.

The stereo amp needs work... one channel is out and the other has a lot of static.

[DaveWM]

well on mine it was the preamp driver transistors, both were bad on one channel causing a lound hiss or rushing sound (I have since been told that transistor can get "noisy". I also replace every single one of the small electros, left the filter alone but may go back and to them too (I only replace the single double cap on the TV as well, the others tested ok, but will prob do them now, sooner rather than later). I picked up some cheap germainum transistor at a suplus store (45cents each) which so far are working fine. I have been trying to get a schematic so I can have some test point for later service, just is case...

Hope your power output transistors are ok, they are expensive. I would recommend you just do a compete recap, with a desoldering gun you can fly..

[DaveWM]

adventures in refinishing...

I hate this part.....

ok got the old cracked disgusting mangled burned difigured etc.. etc.. etc..

off the top trim (not the sliding top just the thick solid wood trim.

did this with a chem stripper and steel wool and sand paper. got a nice blonde wood, very smooth. Used a sealer (the lowes guy said too) then applied a dark walnut stain (the color on the can top looked right). Oil base, messy uck. Well it just sat there did not hardly stain anything. I tried leaving it on, applying heavy, applying light lotsa coats. Maybe 1/2 as dark as it should be. I tried light sanding in between coats, one time I left it on heavy and for a long time, barely got it off, had to resort to aggessive sanding and steel wool to get it off...

the best results were light coats barely enough to have to wipe off.

I am going to get some darker stain and try again.

If the rest of the finish was messed up I would not mind the color, but it is no where near a match I and don't want to have to strip the whole thing.

[DaveWM]

I'll post a pic tomorrow with it working and the top with the PITA finish...

Trying to locate one of these "phantom" remotes, I will keep an eye on praybay.

I have not even looked at the remotes chassis, I dont see any tubes so I am guess it is solid state to operate the relays.

Got a lead on another maggie console tv, I may just have to get another.

[DaveWM]

pics, WIP on the finish.

The TV pic is better than shown in the picture, the camera seems to pick up bars that are not there.

If anybody has a tuner face plate they want to get rid of cheap let me know. The one I have is pretty worn. I am hoping to find one that shows the TV position.

the Black plug to the tuner goes into the newly installed RCA jack, right next to the orig mono input. I can put the two together with a Y connector to run the original audio out from the TV chassis, or do like I have here, direct to the L and R from the DVD.

[Reece]

Dave, you'll probably find it gets better as you use it and the moisture bakes out of the coils and all. You could even put a couple of light bulbs inside 24 hours to add some heat when the set is turned off. Final tweaking to come after the long bake-off.

Reece

[DaveWM]

indeed i have noticed it is getting better, even the vert height has improved with use.

Refinishing

I got another stain, this one seem a little darker and thinner (minwax oil based dark walnut). I think I will get what I want with a few more applications. This is on the top trim.

the sliding top doors are another story. I put on the chem stripper to get the old finish off, this time though its not a toned finish, the wood remains dark after stripping.

I then hit it with some 120 grit in an orbital sander to get the deep scratches out. Finished up sanding with some 320 grit. The tops are solid, about 3/8 thick.

They clean up very very well. I put some sanding sealer on it and the grain really pops and has a beautiful rich color. No staining needed here.

I will just use an oil finish and later a paste wax.

I can then final stain the trim to get as good a match as possible to the finished sliding top doors.

Its really coming along nicely. I figure it will take up residence in the house in about a week. I will get some pics when it is all done. I am feeling pretty good about it.

[DaveWM]

got a NOS picture tube off praybay, hope it gets here in one piece. Figured I should have a spare.