B&K 1076 TV analyst - Page 4 - Videokarma.org TV - Video

DaveWM · #46 04-09-2010, 09:12 PM

power up went well, about 500ma AC at 120v, no smoke, no issues. Nice purple raster came up. That is about the extent of testing tonight.

I will give it a rest and try hooking it up tomorrow to a TV.

bandersen · #47 04-09-2010, 09:45 PM

Cool - I like that purple glow

Good luck tomorrow.

DaveWM · #48 04-10-2010, 03:30 PM

works, got a pic and tone. Now I need to try it out on a few different sets. The Emerson was ok, the predicta barely strong enough RF. I have a 80's era SS set I will try it on. I was not able to see a hammer on the sync pulse line at all on either set, the emerson had better lineairity (much) so not sure what is going on.

I have not checked ANY of the tubes so I will start with some of the RF out tubes to make sure they are ok. I am assuming there may need to be some adjustments as well due to the replacement of some caps on the Sweep board, but I will hold off on that until all else has been checked.

DaveWM · #49 04-10-2010, 06:11 PM

gonna need some work..

pic on the newer TV is pretty linear, but sync tears some at the top, RF needs to be turned up near full, horz adj is at one extreme, just barely locks, has a lot of snow.

color bars work ok, but not great, kinda washed out, and the adj seems to have minimal effect. RF output is only good on two of the channels.

The 1st thing I will try is cleaning the RF channel selector. I replaced several of the weak old tubes (12at7 and 12au7). I need to find a strong 6cb6, I think it is part of the RF. I replace it with a stronger tube and the pic went away. Put the orig back in. I dont know maybe its critical on the tuning.

My guess is the horz is just going to be an adj of a trimmer pot to bring the horz adj control back into center range.

The scanned image was also to big, and offset. This was the cas on 3 different sets. I will be doing some reading up on how that is adj. My guess is the CRT is under scanning, but that is just a guess.

I will need to check the voltages before going too far to make sure all is good on the B+. It uses a 6ca4 dual diode, that has not yet been checked.

DaveWM · #50 04-10-2010, 07:20 PM

cleaning the channel selector switch did wonders for getting the other channels working. But now I am getting some intermittent pie crust in the image, and shifting. Resolution is pretty good, I can see the scratches and dirt on the transparency.

Getting good video signal, I can see the bulleye gradients for contrast, and 325 lines on the vertical not as good on the horz.

old_tv_nut · #51 04-10-2010, 08:10 PM

Quote:

Originally Posted by DaveWM

I was not able to see a hammer on the sync pulse line at all on either set,

I would not expect a standard hammer pattern from this device - it's likely just a wide sync pulse for vertical. (not near a schematic to check at this time)

DaveWM · #52 04-10-2010, 08:30 PM

been messing a bit more with it, getting better, I need to do a good cleaning of the tube pins and the pots. I opened up the vert scan a bit (it was not lighting up the whole of the transparency). The RF antenuator is a little rough. Fun little device.

DaveWM · #53 04-11-2010, 01:51 PM

a bunch of very weak tubes. Next up is the color pot. it turns on and off but seems to have no effect other than the switch. I get bars but the pot does nothing.

DaveWM · #54 04-14-2010, 02:40 PM

Well I got the cap today, very pretty, almost too pretty to put in the tester.
Its a cross over cap, I am sure meant for the audiophiles out there.

Its pretty big, but not much different than what is in there (a little shorter and a little fatter).

After putting this in I will button it up and get to work on the transparencies.