Question on CTM644 - Very dark picture

CanonMan · 14:27, 13 March 15

Quote from: roy bates on 12:56, 13 March 15
whats wrong with that method?

What's right with it? Think about it...

roy bates · 14:41, 13 March 15

Quote from: CanonMan on 14:27, 13 March 15

What's right with it? Think about it...

i did think about it,lol...so would you like to explain?

Bryce · 14:53, 13 March 15

If you use a "bare" screwdriver like this one: http://www.hubertuy.com/wp-content/uploads/2015/02/screwdriver.png
Then there's a good chance that the voltage will arc to your hand. Not good.
Better to use an electricians (insulated) screwdriver: http://www.hyperclaw.com/pic/products/vde_philips_screwdriver_L.jpg
But even then... If a jobs worth doing, it's worth doing properly. And proper jobs are done with proper tools.

Bryce.

The Last Bandit · 16:44, 13 March 15

You're better off with a flat blade, those philips/posi are a bugger to get under the anode cap

Shielded long screwdriver, bit of wire and a croc clip has served be well on a variety of TV & monitors. 22KV seems a bit high for the CTM644 though, my 19" arcade crt is about that. General rule of thumb is approx 1KV per inch plus a few KV.
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roy bates · 17:43, 13 March 15

a 14 inch crt's yields about 15kv.

ivarf · 22:55, 13 March 15

Quote from: Bryce on 12:53, 11 March 15
The knobs on the back off a CTM644 are to adjust V-Hold and H-Hold. They will not have any effect on the brightness of the picture and due to their age, only turn them if you really have to

Did they remove the brightness pot from the back of later models? The 464 colour monitor had it

pelrun · 05:53, 14 March 15

The external brightness pot for a CTM644 is on the right side, not the back. But it's limited (you don't want the consumer burning out the tube!) and requires the internal sub-brightness pot to be adjusted properly.

ivarf · 08:56, 14 March 15

I remember one at the back as well. It might have been a hole in the case where you had access to the potmeter with a screwdriver

Bryce · 17:45, 14 March 15

@Canonman: Of course a flat head would be used. My example was just to show the type of insulation.

@Roy: 15KV hurts too

Bryce.

Gesendet von meinem Motorola DynaTEC 8000X mit Tapatalk 2.

roy bates · 18:59, 14 March 15

bryce,

15kv will more than hurt mate.

kevin.c · 20:21, 14 March 15

Thanks God, discharging the LCD is much more safe.

roy bates · 23:18, 14 March 15

i like working on crt's so i dont really worry about it myself

i would rather have a crt than a lcd for sure..especially on older machines like cpc's

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Question on CTM644 - Very dark picture