View Full Version : CRT for Hitachi CT1342?


asynchronousman
11-25-2004, 08:41 AM
What CRT does this set use, or which replacement might be available for it? The set picks out weak UHF signals like they are going out of style--with only a cheap loop that it came with! But it looks like this...and blue screens are crimson/blood red!

asynchronousman
11-25-2004, 08:46 AM
Set is dated 1985, rotary tuning and everything else is SWEET! I paid $35 for it, and but for the color it was much better than the nearly new Trinitron from 1980. It is the TV equivalent of a great AM DXing machine.

andy
11-25-2004, 10:21 AM
These CRTs are pretty interchangeable. Find any junker with the same screen size and neck size and it should work fine. Even one from a modern TV should work.

jstout66
11-25-2004, 10:55 AM
I'm not sure if that would work... Aren't the yokes glued on in in-line CRT's? Someone should have a Sams, but if not, take the back off and get the number off the tube and check around at Hawkeye or any CRT rebuilder. I need to get with it, and check on a tube myself. I have an early 80's Quasar console that is in a nice cabinet and has Dolby surround stereo and all the inputs. The tube has been getting worse and worse, I may just try to rejuvinate it, which is what you might try. Good Luck!

andy
11-25-2004, 11:29 AM
RCA is pretty much the only one to use bonded yokes. I've never seen in on a Japanese set unless they were using an RCA/Thomson CRT.

Bill R
11-25-2004, 03:04 PM
The CRT is a 370LGB22. Looks like you may have problem with the Chroma processing in IC501 or its associated circuits though. You may not need a CRT. It is in Sams 2335-1

Bill R

Doug
11-25-2004, 08:24 PM
Problems I've run into on some using other tubes are the mounting ears position , curvature of front glass and deflection angle of yoke.
Make sure to check the filter capacitor on the 200v(approximate) supply to RGB outputs.

asynchronousman
11-25-2004, 11:31 PM
I'll be sure to do that. Since I've never so much as messed with one yet finding one will be fun. Fixing the Eico 221 VTVM that is not working will be first. Will let you know at some point.

kc8adu
11-26-2004, 06:57 PM
looks like it is making good white so the crt is likely ok.
did you try degaussing?does the tint do anything?
cant tell much from your pic.
i keep lots of those type crt's since they go in no arm bandits(video poker)
but i doubt you need a crt.
hitachi made good tubes.

asynchronousman
11-26-2004, 08:02 PM
I don't have any advanced equipment beyond my soldering iron (and I need to thank Gary for that, thanks for the reminder) and an EICO 221 VTVM that needs repair (thanks again). The best I can manage is a washed out brown scale like an old colorized 1890's photo. The "blue screen" of most VCR's comes out a cross between tomato sauce, blood and a "Coca-Cola" disk sign, kinda darker red. The AFT (marked ST) was on and that actually improved it.

Here's a couple of lousy shots of my Sony KV-1923 (1980) with a good CRT, just not taken at the right points in the scan but the color's as close as it will get right now. Bowtie that came with the set.

kc8adu
11-27-2004, 04:04 AM
do you have a bulk tape eraser?
a weller soldering gun?
spikes and failed degaussing thermisters can magnetize the crt and cause what you have.
could be a chroma issue too.
try turning up the bias on 1 color and see if that color actually increases.
so if you crank up the blue bias and red increases you know you have a purity issue.

asynchronousman
11-27-2004, 04:56 AM
Refine your definition of "turning up the bias" please. It has color, hue and tint if anything and an AFT/color/contrast type switch. I do know that when you adjust for the "best" color picture the bright "blue" screen generated by many VCRs is blood red and green is more bluish. It took some effort to prevent it from looking like "Halloween" or two-color process movie films, which is why my original beliefs have leaned towards a bad gun. If I recall, it may affect colors in the way you've mentioned. I also recall the the color was much better when I bought it at a yard sale 3-5 years ago.

asynchronousman
11-27-2004, 04:58 AM
The CRT is a 370LGB22. Looks like you may have problem with the Chroma processing in IC501 or its associated circuits though. You may not need a CRT. It is in Sams 2335-1

Bill R

If you have a scan in PDF or even DJVU, it would be great of you to send. PM me if you will.

kc8adu
11-27-2004, 06:57 PM
Refine your definition of "turning up the bias" please. It has color, hue and tint if anything and an AFT/color/contrast type switch. I do know that when you adjust for the "best" color picture the bright "blue" screen generated by many VCRs is blood red and green is more bluish. It took some effort to prevent it from looking like "Halloween" or two-color process movie films, which is why my original beliefs have leaned towards a bad gun. If I recall, it may affect colors in the way you've mentioned. I also recall the the color was much better when I bought it at a yard sale 3-5 years ago.
turn the color all the way down.
on the crt socket board you will find controlls marked drive and bias or background.
the bias adjusts the background and the drives the bright areas.
there is a drive and bias for each color.
if you turn up the red bias and the background goes red its not a purity issue.
try to borrow a degausser or bulk tape eraser and degauss tht tube.
looks more like bad purity in the(poor) pic you posted.

asynchronousman
11-27-2004, 10:30 PM
Ok, so I'll have to take the back off. I hope if it's interlocked like my tube sets are that the Norelco cord will work...degaussing is something the vacuum/TV repair shop on the other side of the tracks will have to look into, though. We are absolute newbies here. Enlightened, not skilled.

By the way, that was the BEST picture a 300 KILOpixel VGA imaging unit will take with no flash and no light in the livingroom (burnt out) using a fluorescent tube fixture as backlighting(the kind you mount under a hutch). I didn't have a scanning sync problem with it like I did in the bedroom on the Trinitron, either, but the colors were correct.