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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc.

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Old 11th May 2020, 9:45 pm   #101
deepspacedaz
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Default Re: Fixing a GEC BT 302 Television

Thank you for the advice
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Old 15th May 2020, 12:11 am   #102
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Default Re: Fixing a GEC BT 302 Television

Hello again. I fired the telly up and all valves glow. Cathode a back glows. But I can hear a really high pitched sound, any ideas
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Old 15th May 2020, 12:52 am   #103
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Default Re: Fixing a GEC BT 302 Television

when I play with horizontal hold frequency changes. can see small dot when I switch off.
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Old 15th May 2020, 8:09 am   #104
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Default Re: Fixing a GEC BT 302 Television

So what was causing the lack of valve heaters?
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Old 15th May 2020, 10:38 am   #105
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Default Re: Fixing a GEC BT 302 Television

Is thats whats happening?
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Old 15th May 2020, 10:43 am   #106
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Default Re: Fixing a GEC BT 302 Television

What is the whining noise its really loud? frequency.
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Old 15th May 2020, 10:51 am   #107
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Default Re: Fixing a GEC BT 302 Television

The whinning is probably the line output stage and if your getting a dot when you switch off chances are your getting EHT.

You should be able to vary the frequency of the whinning with the line hold control.

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Old 15th May 2020, 11:09 am   #108
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Default Re: Fixing a GEC BT 302 Television

Ok so its a good start then there's something happening
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Old 15th May 2020, 11:12 am   #109
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Default Re: Fixing a GEC BT 302 Television

Should I able to use some static or will I need a signal for that
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Old 15th May 2020, 11:32 am   #110
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Default Re: Fixing a GEC BT 302 Television

Quote:
Originally Posted by deepspacedaz View Post
Should I able to use some static or will I need a signal for that
If you click on the "Quote" button in an individual post, you can then add your reply/comment to it. That way, we will all know to what you are referring. Otherwise, it is often far from clear.
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Old 15th May 2020, 11:54 am   #111
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Default Re: Fixing a GEC BT 302 Television

Thanks for the advice
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Old 15th May 2020, 12:17 pm   #112
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Default Re: Fixing a GEC BT 302 Television

Quote:
Originally Posted by Heatercathodeshort View Post
So what was causing the lack of valve heaters?
As Heatercathodeshort asked earlier, can you tell us what was causing none of the heaters to light up, please?
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Old 15th May 2020, 12:22 pm   #113
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Default Re: Fixing a GEC BT 302 Television

All I could figure out was possibly the fuse, I couldn't find anything in the posts relating to a defective heater chain per se unless I missed it.

Lawrence.
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Old 15th May 2020, 12:24 pm   #114
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Default Re: Fixing a GEC BT 302 Television

Post #36 onwards. It's unclear what the situation actually was though.
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Old 15th May 2020, 12:26 pm   #115
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Default Re: Fixing a GEC BT 302 Television

Ok, the situation is I switch on tv. It makes a high pitched whine sound. No picture but when I switch off I see the classic white dot
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Old 15th May 2020, 12:28 pm   #116
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Default Re: Fixing a GEC BT 302 Television

I had the valves checked yesterday some are a little weak but ok. I can list them if you like. I colour coordinated them but they may have got mixed up. Trouble is Ihe some valves labels have worn off ?
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Old 15th May 2020, 12:46 pm   #117
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Default Re: Fixing a GEC BT 302 Television

So it sounds like you ready to put a signal in to it next. It will not display any static, just a blank screen that may be brighter if the brightness is right up
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Old 15th May 2020, 12:53 pm   #118
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Default Re: Fixing a GEC BT 302 Television

If the valves are wrong will i t screw it up ?
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Old 15th May 2020, 12:59 pm   #119
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Default Re: Fixing a GEC BT 302 Television

If you got the result with the white dot with switch off earlier then its unlikely to be disastrous. If a signal is applied and everything is in correctly you would likely see something on screen which would then let you know what's needed next.
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Old 15th May 2020, 1:27 pm   #120
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Default Re: Fixing a GEC BT 302 Television

So i need to put a signal through
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