ukVac.com Homepage
Forum Home Forum Home > Arcade > General Arcade Discussion
  New Posts New Posts RSS Feed - The Amplifergifone TX14-V vector monitor
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Skin:


The Amplifergifone TX14-V vector monitor

 Post Reply Post Reply Page  123 4>
Author
Message
 Rating: Topic Rating: 8 Votes, Average 4.50  Topic Search Topic Search  Topic Options Topic Options
Mitchell Gant View Drop Down
Senior Member
Senior Member
Avatar

Joined: 25 Nov 2011
Location: Chez Vegas
Status: Offline
Points: 6506

Feedback: 5
Post Options Post Options   Thanks (3) Thanks(3)   Quote Mitchell Gant Quote  Post ReplyReply Direct Link To This Post Topic: The Amplifergifone TX14-V vector monitor
    Posted: 07 Oct 2012 at 8:01pm


So you could be posh and buy a used GO5 from Alpha1

OR

you could take a look at the new AmpliFergifone TX14-V vector monitor from Heath-Robinson Industries Inc.

OK, so it may be larger, more expensive, less reliable, more fragile, produce lower quality images and only have a limited production run (of 1), but so what?!?!? It's hardly an excuse to buy a proper vector monitor, is it?

And so what if there are minor issues like the X axis mirrored, or no Z blanking (yet)? Or that it smells of hot, old electronics? 

Chances are it will work longer than the Atari AVG chip on the Space Duel board that's generating the vectors... It lasted almost 30 minutes of 'on' time since I got the PCB a few weeks ago before it popped it's clogs. Fortunately I found a spare AVG chip that still worked (As well as 2 more that didn't of course!)

I'm amazed it worked at all actually, all I did was re-wound the vertical yoke coils and guessed about 80 turns for each half, then wired it to a Star Wars deflection board that I'd repaired. It didn't work at first as I'd got both halves opposing each other magnetically. Duh! A quick swap of wires and these images popped up. I wasn't sure if I'd correctly repaired the deflection PCB either, and it's running on a lower AC voltage too (18-0-18 VAC).




Boy, is this a machine!
Back to Top
tb lilley View Drop Down
Senior Member
Senior Member
Avatar
5 Star

Joined: 08 Jul 2010
Location: Sheffield
Status: Offline
Points: 6110

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote tb lilley Quote  Post ReplyReply Direct Link To This Post Posted: 07 Oct 2012 at 8:15pm
Impressive.

So, yoke rewinding .... What sort of yoke did you rewind? I looked into this recently, but its pretty much impossible to rewind the horizontal, so what reading (I'm assuming pretty low impedance) do you get from the horizontal coil?
Back to Top
Mitchell Gant View Drop Down
Senior Member
Senior Member
Avatar

Joined: 25 Nov 2011
Location: Chez Vegas
Status: Offline
Points: 6506

Feedback: 5
Post Options Post Options   Thanks (1) Thanks(1)   Quote Mitchell Gant Quote  Post ReplyReply Direct Link To This Post Posted: 07 Oct 2012 at 8:58pm
Originally posted by tb lilley tb lilley wrote:

Impressive.

So, yoke rewinding .... What sort of yoke did you rewind? I looked into this recently, but its pretty much impossible to rewind the horizontal, so what reading (I'm assuming pretty low impedance) do you get from the horizontal coil?


It's a Ferguson TX14 TV that was salvaged, so it's the yoke that was on it that I've taken apart.

By a little careful picking away at glue I managed to get the vertical yoke/ferrite cores off and leave the horizontal part underneath intact.

Resistance is not really that important, it's the inductance that matters. More will mean slower current changes at a fixed supply voltage, so slower vector drawing ability. Normal TV vertical coils have a high inductance 10's of mH from lots of turns of thinner wire, which is why the resistance is higher than the H coils. In a TV the vertical coils can have more turns (and inductance) as the vertical scan is slow (50 or 60Hz). This means that you don't need to drive as much current through the coils for a given screen deflection, so less power required.

With the vertical part and ferrites cores still on the yoke, the horizontal measured about 450uH (microhenries) and about 1 ohm resistance on my LCR meter. I guessed this would be fine for the X amplifier, and seems to be OK judging from the result.

The vertical yoke coils were several milli-henries and about 25 ohms resistance, because of lots of turns of much thinner wire. I removed all the wire from the ferrite cores and re-wound with some (about?) 0.5mm wire I found.

At first I tried 50 turns on each core half, wired both in parallel in what I *thought* was the correct way around and got very little Y deflection. Then I added another 30 turns as I thought it seemed logical that more turns= more magnetic field= more deflection. But the result was the same, hardly any Y deflection.

Then I tried swapping the wires on one of the coils and measured it. Now I got about 250uH I think it was (I'll check actual results tomorrow if I get time). This time it worked and I got the picture shown above. I was quite surprised as I thought I'd got the coil wiring correct, so it was trial and error that I swapped it! So at first both coil halves were opposing each other magnetically.

I'll re-measure all the values and report back when I get chance.

Boy, is this a machine!
Back to Top
tb lilley View Drop Down
Senior Member
Senior Member
Avatar
5 Star

Joined: 08 Jul 2010
Location: Sheffield
Status: Offline
Points: 6110

Feedback: 5
Post Options Post Options   Thanks (1) Thanks(1)   Quote tb lilley Quote  Post ReplyReply Direct Link To This Post Posted: 07 Oct 2012 at 9:45pm
Ta.

I was recently in contact with Jrok about this. Here's what he said:

"I used the stock yoke from a low impedance Happ Vision Pro/Kortek monitor. I think the inner horiz winding would be just too hard to do by hand. You'd almost certainly have to build some kind of cust winding rig for it. In theory... almost any standard 90 degree yoke should be suitable as all rasters have very fast horiz deflection for the retrace. IIRC, the Horiz retrace on the yoke I used was listed as about 3 micro-seconds."

He's got a page up detailing his work:

Link

Edited by tb lilley - 07 Oct 2012 at 9:46pm
Back to Top
Alpha1 View Drop Down
Admin Group
Admin Group
Avatar
Do the Shake and 'VAC

5 Years of Supporting ukvac.com!

5 Years of Supporting ukvac.com!



Joined: 06 Jan 2001
Location: nr Southampton
Status: Online
Points: 125025

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote Alpha1 Quote  Post ReplyReply Direct Link To This Post Posted: 07 Oct 2012 at 10:16pm
very cool!
Wanted: Time Traveller, GALAXIAN 3 THEATER, 80's Namco & Taito games

Back to Top
Equites View Drop Down
Senior Members
Senior Members
Avatar
Chief Sheesher®

5 Years of Supporting ukvac.com!

5 Years of Supporting ukvac.com!



Joined: 28 Jun 2010
Location: Warrington
Status: Offline
Points: 21837

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote Equites Quote  Post ReplyReply Direct Link To This Post Posted: 07 Oct 2012 at 11:42pm
Fantastic thread, keep it coming - impressive stuff.
Back to Top
Mitchell Gant View Drop Down
Senior Member
Senior Member
Avatar

Joined: 25 Nov 2011
Location: Chez Vegas
Status: Offline
Points: 6506

Feedback: 5
Post Options Post Options   Thanks (1) Thanks(1)   Quote Mitchell Gant Quote  Post ReplyReply Direct Link To This Post Posted: 08 Oct 2012 at 1:49pm


A little lunchtime fiddling (non-Savile type I hasten to add!) has yielded some more results.

First I now notice the TV is a Philips not a Ferguson that I thought it was. So it should be an Ampliphilifone instead!

I've added Z blanking by routing the Space Duel Z output into the TV's video input driver, and remove the VBlank circuit from the TV.

The picture is quite dull, nowhere near a real GO5, and it also seems to be much dimmer near the centre of the screen, doesn't show so much on the photos as it really is. No idea what could cause this! Turning the screen brightness up also make focus worse. I need to check the voltages and see if they are what they should be. I suspect removing the horizontal scan coil has affected the TV flyback circuit.

There was a small magnet glued to the top of the original yoke, and balancing this back on top of the rewound yoke makes the picture a bit more square. I'm not sure whether the Space Duel's pincushion circuitry is helping or making it worse here.

I've measured the yoke inductances with my Peak Atlas LCR40 LCR meter and got the following results:

Measurements taken with yoke assembled and in place on CRT neck.

AmpliFergifone:

Horizontal (original TV) winding
450uH 0.8R
Vertical winding. First attempt, about 90 turns on each core, wired in parallel
230uH 0.7R


Star Wars 19" Amplifone

X/Horiz
830uH 0.8R
Y/Vert
960uH 0.4R


Goodmans 19" TV donor for colour vector rewind (next mission!)

Horizontal (original TV) winding
1.9mH 1.8R
Vertical (original TV) winding
26mH 14R

It looks like my windings are quite low inductance, which suggests I have not put enough turns on. But the picture is tall enough, which shows that there is enough magnetic field to deflect the beam properly.

Looking at a real Amplifone shows almost 1mH for both X and Y windings, though I notice Y is higher than X. This may just be due to how the windings are physically arranged. Inductance is not simply number of turns, but what geometry and core materials are in there too.






Edited by Mitchell Gant - 08 Oct 2012 at 1:51pm
Boy, is this a machine!
Back to Top
IDCHAPPY View Drop Down
Moderator Group
Moderator Group
Avatar
KANFU Master

Joined: 01 May 2011
Location: Edinburgh
Status: Offline
Points: 21668

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote IDCHAPPY Quote  Post ReplyReply Direct Link To This Post Posted: 08 Oct 2012 at 4:42pm
Awesome  work Big smile
We are the 45
Back to Top
Mitchell Gant View Drop Down
Senior Member
Senior Member
Avatar

Joined: 25 Nov 2011
Location: Chez Vegas
Status: Offline
Points: 6506

Feedback: 5
Post Options Post Options   Thanks (1) Thanks(1)   Quote Mitchell Gant Quote  Post ReplyReply Direct Link To This Post Posted: 08 Oct 2012 at 9:46pm

More progress.

I've measured the TV flyback voltages compared to what the Philips service manual says they should be and they're all low. I thought this might be the case as I've removed the horizontal coil from the flyback circuit. In fact I'm surprised it worked as much as it did without the horizontal coil in the circuit.

I did try to 'vectorise' a VGA monitor but that would not generate any flyback voltage at all once the horizontal coil was disconnected. I gave up on that and gave the CRT to my friend who de-vacuumed it, and with the aid of an axe removed the shadow mask gauze for projection Moire effects... but that's another story.

I had saved the yoke that was from the VGA monitor and it's horizontal coil measures about 500uH. Soldering this in place of the original H coil did the trick (see photo). I now have much better CRT voltages and the image is now much brighter and sharper. It now shows pretty good greyscale shades from the gameboard.

I had to turn up the X and Y sizes quite a lot as the new image size was much smaller now. Lower CRT anode voltage would need less magnetic field and therefore less yoke current to deflect the beam by a given amount.

It's not a perfect image as there is some noise on the vectors, you can see it on the greyscale test screen photo below if you look closely. This could be because I'm running the deflection board from only 18-0-18V AC. Also there could be some magnetic effects from the extra flyback yoke coil on the bench next to it!

But it's a much better result than I expected from some trial and error coil winding and TV hacking.


Boy, is this a machine!
Back to Top
Mitchell Gant View Drop Down
Senior Member
Senior Member
Avatar

Joined: 25 Nov 2011
Location: Chez Vegas
Status: Offline
Points: 6506

Feedback: 5
Post Options Post Options   Thanks (1) Thanks(1)   Quote Mitchell Gant Quote  Post ReplyReply Direct Link To This Post Posted: 08 Oct 2012 at 10:38pm

So here is the real AmpliFergifone, a 20" colour vectorised TV.

I've used an Amplifone deflection and HV board to generate the CRT voltages this time, though I think the EHT is a little low and I have no EHT probe to adjust it. Colours are fairly dull especially red. Though it is a very old TV I picked up for free, so it could just be a crap tube.

Vertical yoke coils were carefully removed while leaving the horizontal yoke in place on the tube neck, so no need to disturb the purity/convergence.

Horizontal coil measures about 1.9mH 3.3R

I wound about 90 turn of 0.63mm magnet wire on to each ferrite core half. It measures about 1.8mH 2.5R, quite a lot higher than the BW Philips yoke I did.

But the results are promising from a quick test!



Boy, is this a machine!
Back to Top
Alpha1 View Drop Down
Admin Group
Admin Group
Avatar
Do the Shake and 'VAC

5 Years of Supporting ukvac.com!

5 Years of Supporting ukvac.com!



Joined: 06 Jan 2001
Location: nr Southampton
Status: Online
Points: 125025

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote Alpha1 Quote  Post ReplyReply Direct Link To This Post Posted: 08 Oct 2012 at 10:57pm
dude that is looking pretty sweet!!
Wanted: Time Traveller, GALAXIAN 3 THEATER, 80's Namco & Taito games

Back to Top
Mitchell Gant View Drop Down
Senior Member
Senior Member
Avatar

Joined: 25 Nov 2011
Location: Chez Vegas
Status: Offline
Points: 6506

Feedback: 5
Post Options Post Options   Thanks (1) Thanks(1)   Quote Mitchell Gant Quote  Post ReplyReply Direct Link To This Post Posted: 15 Oct 2012 at 2:05pm

I'm on to vector monitor conversion number 3 now, a 19" Goodmans TV with re-wound vertical yoke coil.

This came together quite quickly after the last two I'd done.

The black and white monitor I'd tried with a proper bought (Farnell) 470uH inductor in place of the large bodged horizontal yoke coil. That is now nice and neat in the HV department.

So next to try to fool the Goodmans TV chassis into generating EHT rather than the Amplifone HV board that I'd been using.

I found a 1.2mH inductor stripped from a switch mode power supply and tried that in place of the horizontal yoke coil. It was a fair bit lower value than the original yoke at 1.8mH, so I wasn't sure if it would work or melt.

I also put a pair of 100R resistors in parallel (that's all I had to hand) to make a 50R load for the original vertical yoke coil, as most newer TV chassis monitor for correct vertical scan currents, and will shut down if not detected.

The modern TV also does not power on when mains is applied, meaning I had to press a 'change channel' button on the front panel to get it to come on. A crackle of EHT told me it was on, and indeed a picture soon appeared with no blanking, so a very bright centre dot.

The image was quite small too, which suggested a higher EHT voltage than the Amplifone was putting out, possibly because of the different inductance in the flyback circuit.

I've got a HV probe on order now as I don't want to cause any damage or X rays! It's already started a small burn in the phosphor at centre, so I need to be more careful with my new precious tube.

I made a short video to show it working:

http://www.youtube.com/watch?v=yj480PKiYD4&feature=youtu.be

The inductor was fairly warm even though I only ran for a maximum of 30 seconds or so (I had it on for longer than the video clip I did). So I'll need to make a beefier inductor with a proper value I think.


Boy, is this a machine!
Back to Top
DanP View Drop Down
Admin Group
Admin Group
Avatar
Whipcracker

5 Years of Supporting ukvac.com!

5 Years of Supporting ukvac.com!



Joined: 17 Apr 2000
Location: Essex
Status: Offline
Points: 6102

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote DanP Quote  Post ReplyReply Direct Link To This Post Posted: 15 Oct 2012 at 2:11pm
Haha great hackery!   It's amazing how quickly burn can occur.  Fascinating project, keep us updated on progress!

Dan
Back to Top
Mitchell Gant View Drop Down
Senior Member
Senior Member
Avatar

Joined: 25 Nov 2011
Location: Chez Vegas
Status: Offline
Points: 6506

Feedback: 5
Post Options Post Options   Thanks (1) Thanks(1)   Quote Mitchell Gant Quote  Post ReplyReply Direct Link To This Post Posted: 15 Oct 2012 at 2:21pm

These look like possible 19" crt donors (vector or raster) for anyone in that area of "daahhnn sarf" London/Essex:

http://www.ebay.co.uk/itm/PHILIPS-19-Portable-Colour-Television-TV-Ex-Condition-With-remote-control-/251155941200?pt=UK_AudioTVElectronics_Video_Televisions&hash=item3a7a0f8750

http://www.ebay.co.uk/itm/philips-19-tv-with-remote-control-/300795963343?pt=UK_AudioTVElectronics_Video_Televisions&hash=item4608d627cf

http://www.ebay.co.uk/itm/BUSH-2203-T-19-inch-television-/120997825509?pt=UK_AudioTVElectronics_Video_Televisions&hash=item1c2c084be5

http://www.ebay.co.uk/itm/television-/190739755310?pt=UK_AudioTVElectronics_Video_Televisions&hash=item2c68f9b12e

Boy, is this a machine!
Back to Top
Mitchell Gant View Drop Down
Senior Member
Senior Member
Avatar

Joined: 25 Nov 2011
Location: Chez Vegas
Status: Offline
Points: 6506

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mitchell Gant Quote  Post ReplyReply Direct Link To This Post Posted: 19 Oct 2012 at 2:26pm

Some small updates to the Goodmans TV vector conversion today.

I've now got a proper 25-0-25V AC transformer for the deflection board which has cured the wavy flicker that was showing when I was running on 18-0-18. No surprise!

I have also re-wired my pair of vertical yoke coils to be in series rather than parallel, this now gives more deflection, so I can turn the Y Size pots down and the circuit runs cooler now. It was working in parallel, but I noticed the Y deflection current sense resistor was warmer than the X one, and I'd had to turn up the Y size to get a square image. So I was having to drive more current for same deflection.

I've also wound a beefier inductor to fool the TV horizontal output. I've got a HV probe too and am measuring a rather hot 28kV on the anode with no beam current. Service manual for TV says 27.5kV max, so I may be running a little hot there! For a 19" CRT that is pretty high compared to a Star Wars Amplifone at 19.5kV. It is bright though!

The game board RGB is now driving the TV original neck PCB RGB amplifiers, bodged via some 1K resistors chosen at random. There is no spot killer circuitry now, and if any of the RGB wires falls off that colour turns itself on FULL power with no blanking and will likely burn the screen pretty quickly.

At first there were a lot of jumpy wiggles on all the vectors, but adding proper twisted pair signal/ground wires for X and Y signals from game to deflection board has cured that. I think I'll need to do the same for the RGB signals too, as per original game wiring loom. I'm sure Atari had all those grounds for good reason!





Boy, is this a machine!
Back to Top
Alpha1 View Drop Down
Admin Group
Admin Group
Avatar
Do the Shake and 'VAC

5 Years of Supporting ukvac.com!

5 Years of Supporting ukvac.com!



Joined: 06 Jan 2001
Location: nr Southampton
Status: Online
Points: 125025

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote Alpha1 Quote  Post ReplyReply Direct Link To This Post Posted: 19 Oct 2012 at 3:27pm
holy crapola the picture looks really great! Kudos dude, that's a great project and result.
Wanted: Time Traveller, GALAXIAN 3 THEATER, 80's Namco & Taito games

Back to Top
karlcdoe View Drop Down
Senior Members
Senior Members
Avatar

Joined: 22 Jan 1999
Location: United Kingdom
Status: Offline
Points: 3263

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote karlcdoe Quote  Post ReplyReply Direct Link To This Post Posted: 19 Oct 2012 at 3:30pm
I trust your good work + JROKs + Dezbaz (any others I've forgotten?) previous studies might finally lead to vector monitor prices becoming sane again, either that of a sudden shortage of CRT tvs :-)

In fact someone somewhere should be stockpiling TVs, there are hundreds at my local tip, probably all working but there's only so much I can take in. Incidentally I passed what looked like a standard ratio 19 or so inch Trinitron just off Southover street in Brighton this morning if anyone wants to rescue it and dry it off. 

Anyhow keep the tech updates coming, looking more interesting all the time...
Back to Top
chadsarcade View Drop Down
Senior Members
Senior Members

Lord of Vectors (tm)

Joined: 02 Feb 1999
Location: Lancs
Status: Offline
Points: 818

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote chadsarcade Quote  Post ReplyReply Direct Link To This Post Posted: 19 Oct 2012 at 4:42pm
Wow - now that is seriously impressive!
Back to Top
P-Man View Drop Down
Senior Members
Senior Members
Avatar
International man of mystery

Joined: 16 Mar 1999
Location: Oakland CA, USA
Status: Offline
Points: 4013

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote P-Man Quote  Post ReplyReply Direct Link To This Post Posted: 20 Oct 2012 at 12:32pm
Do you have a microwave radiation meter? get one... 28kv seems high for a small CRT like that, dont want to sterilise yourself...

I hacked up a vga monitor a year back or so, i did get deflection but didn't hook up the Z's and lost out on time. I had the usual issues with the monitor not powering up unless it had a sync signal in the correct vga range. I attempted to make a valid sync signal from some 555 timers but ran out of effort and havn't picked it up since.  (i was using a 60-in-1 for the valid vga signal during testing) I got HV but didn't measure it, i was surprised it powered up the hv with the yoke disconnected.

A VGA crt gives you pinpoint sharp vectors as the dot pitch is much much finer than a normal tv, which is probably not good for playing vector games where you do need thicker vectors really. I figured it might be good for test bench purposes though.

You've inspired me to look at the project again sometime soon, i've always fancied a 14" colour vector on my testbench.

How have you found the convergence to be after you have messed with the yoke re-winding though?


Edited by P-Man - 20 Oct 2012 at 12:34pm
Andrew Welburn www.andys-arcade.com
Back to Top
Muppz View Drop Down
Senior Member
Senior Member


Joined: 26 Jan 2012
Location: Alfreton
Status: Offline
Points: 805

Feedback: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote Muppz Quote  Post ReplyReply Direct Link To This Post Posted: 20 Oct 2012 at 1:17pm
one word - AWESOME
 
maybe its time to visit loscoe tip to rescue some tellies.
Hand Soldering 160-Pin QFPs since 1994.
Back to Top
 Post Reply Post Reply Page  123 4>
  Share Topic   

Forum Jump Forum Permissions View Drop Down



This page was generated in 1.471 seconds.