slyvania roundie

[DaveWM]

I have a B&K 1076, I can try a few things with it. Its out in the garage, but will be coming in soon, should be easier to work on then. the plan will be to try injecting a composite signal and see if that works better. I also plan to scope the output from the detector diode and compare that to the composiit signal from the digital TV tuner. I have done that in the past just to see how well the RF/IF/detector are working (by comparing the dvd comp signal on one trace with the comp from the set on the other). that gives a real good indication of how well the tuner and IF alignment are working.

I have gone thru and replaced or checked just about eveything in the vert osc section, the only thing left I I have not checked (since I dont really know how) is the VDR, but I have one coming soon so I will just replace that. its the one right after the .0082 cap from the plate of the vert out.

[DaveWM]

finally got it in the house, vert pairing does not seem to be an issue anymore, but now the pic seems noisy, dont recall if that is a new problems, like a weak RF amp tube. could also be related to agc, so I will try a new RF amp tube AND a bias supply on the RF just to see.

There is a tuner subber locally for sale, I am thinking about getting that, seems like a fast way to clear a tuner.

I nver did get the scope out and go over the video signal again. too lazy I guess.

oh and even thru the noise I can see the same kind of ghost as the maggie has (both are CTC-15/16 clones). So either they both have a design flaw, or they both have the same problem, or my signal is bad. Not something I am overly worried about.

[Chad Hauris]

If you have another known good set with a transformer power supply (or a hot chassis set with an isolation transformer) this can work good as a tuner check out device. It doesn't matter if it's color or black and white. If you suspect tuner problems in the suspect set, sub in the test set's tuner using the 45 mhz IF output and if you suspect IF problems in the suspect set, hook its tuner IF output to the test set's IF input.

I used a Zenith B/W set with a solid state tuner this way to help find problems in an RCA CTC-28. The picture was very weak and snowy but the RCA set's tuner produced a good picture on the Zenith set. It turned out to have one bad IF tube and and bad 1st video tube.