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Old 05-29-2016, 04:18 PM
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Sencore VG91 very erratic please help

This thing has got me stumped. I sat and tried to work with this thing for half an hour, and the closest I got was a bunch of very fuzzy test patterns. The pictures represent the closest I coud get with the fine tuning.
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Old 05-29-2016, 04:19 PM
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Another.
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Old 05-29-2016, 05:01 PM
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Do you have the output frequency set for the proper OTA channel (not cable channel, IF, etc?). Connected directly to antenna terminals thru balun (if needed)? RF output level set properly for antenna connection?

Most Sencore gear of that era has a pullout quick reference guide attached to the bottom of the cabinet. Have you read it (or the full manual?)
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Old 05-29-2016, 05:15 PM
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I did attempt to read the manual, but it did not make much sense to me. I set all the controls by the instructions for NTSC patterns, and this is what I got. I found that I got better signal by plugging in an RCA cable to the "Standard Video Out" plug than with the BNC plug that I paid $10 for. The RCA cable goes to two gator leads that go on the VHF terminals. This method worked for my Sencore CG159.
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Old 05-29-2016, 09:53 PM
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The "standard video out" provides just that-- a VIDEO SIGNAL. You could feed this in through a composite input on a newer TV. To go in through the antenna you need a modulated RF signal. This is available from the "RF/IF output" jack. Set the output mode to standard TV, select whatever channel you want, and bring up the RF signal level to get a solid picture.
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Old 05-30-2016, 08:29 AM
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But when I did that with the BNC connector, I got nothing.
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Old 05-30-2016, 12:51 PM
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Quote:
Originally Posted by TUD1 View Post
But when I did that with the BNC connector, I got nothing.
Several possibilities:

1. TV tuner bad... is this the TV that did not work well on VHF. did you try it on UHF?

2. Improper settings of the generator... read over the manual again, you need to understand how it to set it up. Ask questions here if something does not make sense.

3. IF/RF output of the generator not working... possibly the reason that this generator was free.

Did you try running the "video output" RCA cable into your modulator?

jr
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Old 05-30-2016, 03:09 PM
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Problem solved! I stopped being an idiot and I realized the RF/IF output was on minimum. I turned it up and now I have all the test patterns I could ask for. And yes, after this, I ran the video output to the Blonder Tongue, and that works excellent as well.
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Old 06-02-2016, 10:52 AM
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Long ago a chief engineer I worked for told me this, "If it worked before, it can work again." I was having a particularly hard time with a Conrac monitor. But I always remembered that. Sometimes you just gotta keep at it.
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