Zenith blonde porthole combination started

[JCFitz]

Starting on the Zenith blonde porthole combo I picked up yesterday. Last night since it had been done already I just plugged in the radio chassis. It fired right up and I got FM reception. The dial cord either came off or broke when I attempted to tune it so I reached in the back and tuned it to the oldies. The controls and selector switches are quite dirty but they work.

AM is dead.No reception or noise at all just a slight hum. The changer works but it looks like it was left on for so long it has developed a flat spot on the idler which thumps every time it goes around. The needle was broken so I popped a new 78 cobra in it and put on a 78. There's lots of static and you can hear the record faintly. The filter can ran quite hot and I could hear and smell it venting a little so it definitely will need restuffing. Might have been ok if I had formed it,maybe not since it may already have been bad or damaged from his power up. So at least the radio chassis works somewhat.


On to what eveybody is waiting for,the tv section. I powered the crt at first at very low voltage to check for filament and that it didn't show signs of glowing bright and burning out which meant it was under vacuum. No problems there. Brought it up to 4v and it was already well within the good, 6.3v brought it up to near 900 0n the scale of my B&K 465.


Went and found a strong 5U4,nos 6BF5 and the only 5Y3 I had which only comes up to 40%. Good enough for testing. Brought it up slowly. Got to 90v and could hear the horizontal whistle and drew a small arc from the rectifier lead of the flyback.After that I turned it back down as the main filter on the power supply was starting to run hot. I'll let it run a while at 40V until it cools down and try to bring it up more slowly. The filters on the tv chassis were cool to the touch. I also heard some static when I turned the volume control so the audio amp is alive. This set just might produce a raster before recapping it yet.It might even work.

[JCFitz]

Here's the nice blonde cabinet. I have the door pulls.Took them off to lay it down for the trip home. It's very nice,has a few battle scars with the right side having some large scrape marks mostly near the bottom.

Also a view inside the pencil box door.

[CoogarXR]

Can't wait to see more!

I love that set.

[JCFitz]

Well I brought it up to full line briefly. There was sound from the tuner and the horizontal stage is definitely working but no high voltage. Tried another 1B3 I know was good.No go.The 4.7ohm resistor is open under the socket according to my continuity tests. Anybody ever have to pry open one of these arrangements? It's a metal holder mounted on top of the doorknob. Wish I had a solid state replacement lying around to get around this to see what I got. If it works otherwise this resistor may be why it was retired.

It had to be brought to full line to wake up the IF and tuner stages so there's some weak tubes or that 5Y3 is causing that.It only brought up to 40 both sections on the scale of my B&K 747. So I need a 5Y3 for sure.

[JCFitz]

Went out looking in my used tube stash. Knew I had saw a solid state rectifier sub there a while back. Found it. It's for a 3DB3 but I figured I'd try it and it worked. Got a vertical line which increased a little as it warmed up. There is no sync and the picture is best when the sound is tuned out(What else is new...lol)

After a few minutes there was static in the speaker and the raster was jumping around. The 6SN7 in the vertical stage was sparking inside. Went and got a 6SN7 and got a half a picture this time. Getting better. I'm gonna drag out my B&K 747 and see what culling out the bad tubes does before I stop powering it up for recapping. I found a strong 5Y3 but it still takes a minute or 2 for the IF and tuner to wake up at full line voltage. Just a raster at 110v.

[ChrisW6ATV]

You are very bold to power up the TV with known-bad filter caps, but it is nice to see how much it is working with the basic steps you have taken.

[JCFitz]

Originally Posted by ChrisW6ATV

You are very bold to power up the TV with known-bad filter caps, but it is nice to see how much it is working with the basic steps you have taken.

I have been told of these working with original capacitors so I had to see for myself and the main filter is running much cooler now. The ones on the main chassis don't even get warm at all.The radio chassis main filter will get restuffed since it already vented a little. Of course I'm running it very briefly and on a variac.All the paper caps will be replaced before it's run very long.

[Microtrol]

you're a lot braver than I on firing it up but looks like you have a very good deal there. Going to check that 4.7 oh resistor in the cup for sure on my unit. All the sand resistors were badly out of spec on my blonde so far. Hope to fire mine up in a couple weeks part willing.

[JCFitz]

Originally Posted by Microtrol

you're a lot braver than I on firing it up but looks like you have a very good deal there. Going to check that 4.7 oh resistor in the cup for sure on my unit. All the sand resistors were badly out of spec on my blonde so far. Hope to fire mine up in a couple weeks part willing.

Well the main filter in the tv power supply seems to have finally formed as it runs cool to the touch but there is a slight background hum in the speaker so it may still need replacement(restuffing) all the others I'll see. All the ones in my Zenith color roundie except one that was bad checked out good for value and esr so the remaining cans in this set may be still good also.

I checked all the tubes.It seems nearly the entire set was retubed with GE tubes in 1963 according to the date code on the tubes. Somebody liked GE tubes.They all checked good. The 2 vertical 6SN7s were Westinghouse. 1 of them was the bad one I replaced. The original Zenith 6AL5 was in there and had a short and I broke the GE 6C4 in the tuner trying to get the shield off. It was a 63 GE tube also but it may have been weak. I get snow and finally a picture when I get between 100 and 110v ac with a new one. Before it took full line voltage to get it from white screen to a picture.

The vertical is still shrunk regardless of the switch position(It does increase when I switch to full screen but not all the way) ,there is no sync and the picture has poor contrast so no further improvement to be gained until I recap it and go over the resistors and clean the controls. So no more powering up on the old papers I promise...lol.

I'll definitely check those sand resistors(Thanks Microtrol) and my flyback needs recoating also. Maybe it's a good idea to replace all the sand resistors.

Doing some cleaning I see a serial no. sticker on the glass bell of the tube before it meets the metal funnel. This may be an original Zenith tube after all.It's definitely a strong one.