Need Help with BK1077B

[Aperna1985]

Hi guys a while back I recapped my B&K 1077b and it worked really well. One day I didn't realize I left it on and I had the two RF output leads touching. Now it won't output to the television. I must have shorted something. I was trying to find a schematic, but everything I find is just for the 1077 (Even directly from BK) and I noticed some of the component values are different. Where can I find a schematic or is there a common failure when this happens?

[Popester]

Do you have the owners manual? I believe it’s in the back pages of the owners manual. It was pretty thick if I remember. Good luck.

[Aperna1985]

I'm going to have to look for it, I think I do

[kf4rca]

Go here: https://antiqueradio.org/BK1077BTelevisionAnalyst.htm
Scroll down halfway down the page and click to enlarge.
I really didn't know there was a "b" model for the 1077.
I knew there was a "B" model for the 1076 which has a jack for external audio in.
Also it has a different phototube which gives it a slightly sharper picture.
Be careful around that phototube or you'll be rigging one of these in there.

[kf4rca]

Another good place for schematics is here:
http://www.pacifictv.ca/wanted.htm

[Aperna1985]

Thank you, I actually just bought a guide off of eBay that explains how to work on them too. At least now I know which tube is which. So now I'll start checking all the sections hopefully I didn't blow up something that isn't replaceable.

[Aperna1985]

I'm still struggling a little with this 1077B. I tore my house apart and found the book. I'm looking at the block diagram, I don't get color bars, or any image from the slides on UHF or VHF. Is it right to assume the problem is in the video phase inverter? Or would the Analyst act like a TV with a dead IF and just create a blank screen. In that case it would be in the RF Modulator.

Here is a link to the block diagram.

https://imgur.com/a/gd0JhUV

[old_tv_nut]

Are you viewing the RF output on a TV or video on a monitor?

Are you seeing snow or a clean blank screen?

[kf4rca]

We're assuming you've got light on the screen.
You didn't unplug the photo-tube and plug it back in. Sometimes the keyway breaks off and that allows you to plug it in any way. Happened to both of my B&K's (1076's)
Something to check.
Something else to check is you should have high voltage on the pins of the phototube.

[Chris K]

I had a bad phototube in mine when I first got it and I had to replace it. This is a great piece of diagnostic equipment but it can be quirky...at least mine has been. I recapped it, both electrolytic and film caps, probably unnecessary to do all, but I wanted to be certain it was sorted.

You said both RF leads were shorted. You mean the RF signal and ground?

[kf4rca]

Is this the guide you bought off Ebay?
https://www.ebay.com/itm/14595267626...Bk9SR870i4f4ZA
It probably assumes you have a scope.
While you're in there you might want to add some video peaking coils to your 1st and 2nd video stages.