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TeamRocketReviews
April 20th, 2012, 06:18 AM
Does anyone actually have one of these?

http://books.google.com/books?id=voPUUGTC56UC&pg=PA205&dq=thomson+ega+monitor&hl=en&sa=X&ei=5W6RT6zOG4qf6QHX1LmLBA&ved=0CFMQ6AEwAw#v=onepage&q&f=false

Maverick1978
April 20th, 2012, 12:09 PM
Not a Thompson... I've a Magnavox EGA.

mikey99
April 20th, 2012, 02:27 PM
I've never seen one of those in person but I have seen the ads before.

The Princeton EGA monitors are also really nice.....
I have a couple IBM 5154 EGA and also a Tatung EGA. I like the
Tatung because it has a cooling fan, but overall I think the picture
on the IBM 5154 is better.

The IBM 5154 was in the same price range.... around $600

TeamRocketReviews
April 24th, 2012, 08:53 AM
Can you show the Tatung in pictures? Just curious. I've never seen a CRT with a fan before.

mikey99
April 24th, 2012, 11:18 AM
I'll take some pictures next time I have the monitor hooked up...... it's a TATUNG CM-1380F
I've never opened the monitor, so I'm not sure if it came stock like that or it was just added by someone.
But I do hear a fan running inside when I power it on :-)

ibmapc
April 24th, 2012, 08:19 PM
I have a Zenith Data Systems EGA monitor that has a cooling fan. It looks original to me.

twolazy
April 24th, 2012, 08:32 PM
Is it a flatscreen zenith? I had one of those, the hypertension monitors. God I miss that thing!

Only EGA I have left is a Unisys 14"

ibmapc
April 24th, 2012, 09:12 PM
No it's an old style curved face 13" CRT. It's starting to show it's age. The edges of the picture are sometimes distorted and the colors are weak, especialy RED. Sometimes it flickers as it warms up. I wonder if some new Capacitors in the power supply would help.

TeamRocketReviews
April 25th, 2012, 05:38 AM
Is this what it looks like?

http://www.zdsparts.com/images/zvm-1380.jpg

ibmapc
April 25th, 2012, 07:50 AM
Yup, That's the one. Anyone know where I might find Schematics for it?

Shadow Lord
April 25th, 2012, 07:54 AM
The IBM 7534 Industrial Series EGA monitor also had a fan. I've posted pictures of it here and so have other members.

Jan3Sobieski
April 25th, 2012, 12:02 PM
Hi TeamRocketReviews,

I just picked this monitor up at an older computer store. It powers on, but I haven't tested it yet. It has 4 way switch on top. As i can't seem to find a manual for it, does anyone have any idea what the switch does?

SpidersWeb
April 25th, 2012, 12:28 PM
Judging by the advert, it probably changes the text colour in text mode.

TeamRocketReviews
April 26th, 2012, 09:34 AM
Which monitor are you referring to?

Jan3Sobieski
April 26th, 2012, 10:30 AM
Which monitor are you referring to?

The one you were asking for in the thread, the Thomson 4460D. Like I wrote, I picked one up from an old computer store. It's missing the base, but it does power on. I will test it out as soon as I get a chance.

PGB1
April 30th, 2012, 12:33 PM
Does anyone actually have one of these?

http://books.google.com/books?id=voPUUGTC56UC&pg=PA205&dq=thomson+ega+monitor&hl=en&sa=X&ei=5W6RT6zOG4qf6QHX1LmLBA&ved=0CFMQ6AEwAw#v=onepage&q&f=false

Hi Everyone!
I was looking for information about connecting a 3-1/2 floppy & a some HDDs that need erasing to my 8088 & came across this forum. I saw this post. I know Im late to the party with the reply, but... Yes, I've got that monitor. I'm actually using it today. Important stuff- Looking at old disks & stuff & junk. It's a blast!

I'm not interested in selling it right now, if that's why you asked. But I will be more than happy to supply any information or photographs you might like. If you need shots of the insides, I'll be happy to open it. (Should be cleaned anyway- It's been wrapped & packed away for ten or more years.)
I'll look to see if I received any documentation for it when I purchased the computer way back in- Huh, I can't remember. I do remember the $2,000.00 part like it was yesterday.

Are you restoring one? It is a great monitor & outlasted several others I've had.

Let me know if I can supply any info,
Paul

Jan3Sobieski
May 9th, 2012, 07:19 AM
Well, tested it out yesterday. Monitor powers on and displays picture. Unfortunately, did some testing and it's missing the red color. The usual "smack" on the monitor doesn't seem to have any effect. Any ideas on where to start troubleshooting? all pins are perfectly fine on the cable so I don't think that's the problem.

Any help would be appreciated.

PGB1
May 9th, 2012, 02:31 PM
Hopefully one of these ideas will solve the problem...

I have a 4460D & vaguely remembered having trouble with a color. I looked in the manual & had left myself a note telling me that a solder joint in the convergence circuit cracked (from heat/cool cycles)- Red was dead. (Details below)

Before Reaching Into The Monitor's Guts:
The bottom of this reply has How-To-Open-The-Case notes.
Be sure the unit is unplugged & the high mfd capacitor is drained. I don't know the 'official' proper way to do this, but an internet search will certainly provide safe details. These can hold charges for months & months. Please be very careful. Usually, the high voltage areas are well marked, but the power, of course, can manifest itself anywhere in the unit. It is also a good idea to wear a grounded wrist strap to dump your own static before it blasts a component in the monitor.

I don't remember where to tell you to look for the convergence circuitry. I think it is usually the board on the back of the CRT. (I learned something new today, so something old fell out. Must have been that.) I'm by no means an electronic repair person, but I've had cracked joints on many circuit boards (mostly entertainment lighting dimmer packs). With an opti-visor or just a good magnifying glass, they are easy to spot. Also look for 'cold' solder joints. They will be dull grey in color. They may conduct fine for years & then quit.

Simple Fixes To Try First:
Sometimes degaussing the CRT can clear up the craziest of problems. I don't see a degauss button on this monitor. A good way to degauss is 1) make sure the unit is plugged into a grounded receptacle if it is 3 prong. If 2 prong, make sure the receptacle is properly polarized (The wide blade goes into the receptacle's neutral. Lots of houses are wired backwards.) These two items will help let the residual (stray) magnetism bleed to earth. 2) Check cleanliness. A TV guy once told me that he sometimes simply cleans greasy dust from cigarette tar or nightclub fog juice off the tube inside to make a variety of problems go away. It can't conduct electricity to dump the built up charge properly. 3) See that the cage, if there is one, is still properly hooked up. It is generally some wires across the back of the CRT. They go to the chassis. If it gets unhooked, there is no way to bleed off the stray current & magnetism.

The cable could be bad or have a bent pin. On yours, if it is the same as my 4460D, Pin 3 is Red & Pin 2 is 2nd Red. If you hold the female end with the wide side up & the holes facing you, pin one is top row, left. It moves right (Pin 5 is last on the top row). The bottom row is pin 6 on the left through pin 9- far right.
You could use a continuity meter from the board the cable terminates on to each pin. (After discharging the capacitor I mentioned above.) But, the male pins on the video card are most easily damaged. Also, there could be dirt or corrosion in the female end. A blast of contact cleaner will clear that out fast.

Last Idea: Did you check the Input Signal/Test Switch? It is the one in front of the power button. Position 1 is RGB 16 or 64 colors. Position 2 is Green Only 3 = Amber Only & 4 = Blue Only. But on mine, if I hit just the right position, I will get everything but blue. So maybe on yours, there is a position where everything but red comes on. Guess it has to do with the video card? I'm not trying to be rude, but if you don't know what this poorly marked switch is for, it is easily overlooked.

The idea you don't want to hear- The red gun is dead. I understand this is unusual, so hopefully it is not the problem.

I hope at least one of these fixes your problem. If not, I've found good information at this web site about all kinds of electronic problems- http://www.eserviceinfo.com/news.php
There is a forum in there with really helpful professionals. (I'll be hitting it tonight. My 6x86's power supply went dead. I can't figure out which component cooked.)

Opening The 4460D Case: (From my napkin notes shoved in the manual)
Remove Back Case- Push in 4 clips. there is one near each corner. Need small spudge or screwdriver
Remove Front- Pry out 2 plastic pions located on the bottom near the front panel. Separate with a wide, flat blade. Unplug the LED
Remove Top- Remove 2 screws at the top, front corners of the screen. Top lifts off.

Again, I hope at least one of these fixes your situation. And, I hope it is one of the easy & free solutions!
Paul

modem7
May 9th, 2012, 04:30 PM
Well, tested it out yesterday. Monitor powers on and displays picture. Unfortunately, did some testing and it's missing the red color. The usual "smack" on the monitor doesn't seem to have any effect. Any ideas on where to start troubleshooting? all pins are perfectly fine on the cable so I don't think that's the problem.
Loss of red in the monitor itself can be caused by the failure of one of many components.

A faulty cable is a possibility. Try bending/flexing the cable at various points, particularly near the ends of the cable.

TeamRocketReviews
May 12th, 2012, 02:20 PM
Post a picture?