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Tech Review: Victor's (8liners/Genao) Replacement Arcade RGB Monitor Chassis (LONG)

P

Pac-Fan

All --

This post is intended to be a summary (though it still got long) review of
Victor Genao's (8liners.com)'s replacement CGA/low-res analog RGB arcade
monitor chassis. A much more thorough review with numerous pictures and
explanations will be posted to a web site (anyone have space?) when time
permits.

If you have personally tried one of his chassis as well, please contact me
and confirm/contrast anything noted below. If you reply you MUST include the
word 'chassis' is the title otherwise your mail will be lost in the spam
deluge, or preferably post to the group.

I am not in anyway related to Victor or his company, just an enthusiast with
enough CRT background to be safe and to be able to try out numerous tubes on
a chassis over a couple evenings. All I have in this is $73 for the chassis,
shipped, plus some old donor tubes, and about 10 hours work (also doing
swaps in a WG arcade chassis). My review is intented to be fair and
impartial based upon MY experiences only. Yours may vary based upon tube and
yoke variations.

Remember: Safety first. Don't attempt this unless you know and understand
all risks of working with CRTs and high voltage.


Summary: A cheap, quick and easy way to make an arcade monitor with (nearly)
any old TV or Arcade tube with their yokes attached.

Results: Vary depending on donor tube type, brand, model, quality, previous
(ab)use, yoke characteristics and other factors. Overal very positive with a
few caveots.

Unit purchased: I purchased the "low impedence" version. Meant for use on
tubes with yokes with vertical windings measuring around 15 ohms DC voltage.
(Technically, yokes work and vary based upon impedence [AC resistance, not
DC] but that's another topic for another post) Low impedence versions are
similar to a Wells-Gardner K4600 series monitor NOT an Electrohome G07 which
is high impedence (~55 ohms, DC).

I have yet to find a TV set with a high impedence yoke that also has the
correct tube pinout. With 5 tubes total, plus testing a WG chassis too,
making for 10 combinations, I didn't want to get into swapping yokes for
"perfect" combinations leading me to do 100+ ? tests along with
reconvergence/etc.. :( The intent of these chassis is for a quick setup
with a tube and its existing yoke...

Overall comments, in no particular order (remember far more detail will be
posted later, with pictures)

- Original RCA 19VJTP22 tube + yoke from a WG K4600 presented a super sharp,
VERY highly focused pixel screen at nearly any (resonable) contrast and/or
brightness. As good or better than the K4600 it came from. However the yoke
suffered from pincushion on the horizontal left and right part of the tube,
bowing inward about an inch in the center making it annoying to use. No way
to adjust it out. (Tube had burn-in but looked good in the chassis with the
new picture on it.)

- 4 different donor TV tubes. A Matsushita dark-tint screen from a mid-80's
Quasar knob tune set (very very faint overall burn-in), 2 Orion tubes from
late 80's Emerson quartz mini-dial and PLL synth tune sets (different tube
model #s), and a Magnavox/NAP/Philips tube from an early 80's Magnavox knob
tune set. Other 3 tubes showed no visible general burn-in.

- All 4 tubes presented colors very well, except the dark tint one that
seemed to be somewhat 'gun worn', which makes sense given the light burn-in
and darker glass. Overall on the all 4, the colors were vibrant and very
adjustable. However all 4 tubes exhibited an overall blurriness that could
NOT be removed using the focus control, even though the edge of the focus
pot was never hit. The only way to get the clarity in each pixel to match
the original WG tube was to adjust the brightness control very low (too low
to place in a game however) At normal brightness levels, basically there
was significant "blooming" around the pixels, especially white, making it an
overall soft, yet, not out-of-focus image.

- All the drive controls, cut-offs, screen and focus were adjusted in every
way trying to 'fix' these problems. However, a bit of background told me it
wouldn't help. You see, I also tested each of these tubes in the WG K4600
chassis and all of them had nearly the same highly focused pixels on the WG
chassis (though they had yoke problems there, where they had outward bowing
pincussion, opposite of what the WG tube did on the 8liners chassis...which
makes sense). I also compared the sharpness against a NOS, basically
unused, Hantarex MTC9000 monitor I have that is brilliantly sharp at even
high contrast/brightness as a basline comparison. (No, I didn't want to swap
that tube in to test...yet)

- Two of the tubes (the dark Matsushita and the Maganvox tube) exhibited
slight pincushion in the lower right corner (assuming the anode cap was on
top for orientation). The horizontal lines were slightly drug towards the
corner in the corner, but it was not so annoying as to make it unplayable
like the large pincusion exhibited by the RCA/WG tube.

- Other than the slight bends noted above, the chassis seemed to handle a
wide variety (9.8 to 14.5 ohm DC vertical) yokes keeping the pictures
straight and only very light geometry issues, but the 8.5 ohm one from the
WG was apparently too different in impedence to work without pincushioning
(and vise versa--the TV yokes in the WG chassis all had pincushion due to
impedence mismatch)


Conclusions:
- Depending on your donor tube luck--If you are looking for a monitor to
present a nice smooth screen, especialy with newer games that have numerous
solid colors and large fonts, you probably will be very happy with the
results. For the MAMErs it will blow away any attempt to use NTSC composite
or Svideo on a standard TV set, it will be better

- If you have older games with not much background and very clean/concise
lines (pac-man, galaxian, etc..) and LIKE seeing very sharp (but round, not
computer crt 'square') pixels, then you may have to look longer for a better
matching tube and/or do a yoke swap to make things match best. (e.g. if my
old RCA tube didn't have bad burn in, I could just swap on any donor yoke
from a TV set and have a really really nice monitor for what I like--sharp
pixels)

- It seems to like the impedence of TV set yokes best, but I only had one
compatible arcade chassis/yoke to compare against so my test sample is
admittedly small.

- The chassis has a wide range of controls and isn't anywhere as limited as
a WG 46xx or EH G07 series chassis. You can control virtually everything
with pots, and there is a "small/medium/large" jumper block to gain even
more size if the HWIDTH and VSIZE controls don't give you enough or too much
size. Unlike many monitors there are THREE drive and THREE cutoff controls,
giving you full (and easy) control over RGB grey and white balancing, which
is good if the donor tube may have a weaker gun than the others. Focus seems
to be very wide..I didn't ever reach the 'edge' of the pot in either
direction when I switched tubes. I did run into that on the old WG chassis
where a donor tube would just be in focus at the extreme left or right of
the pot.

- Built in switch-mode isolation transformer is nice so you don't need a
huge heavy copper wound iso. It includes a very cheap line cord with AC end.
I was annoyed it was not keyed hot (small) and neutral (wide), as techically
it's safer to run the hot in through the fuse first and not the neutral. But
I just labeled the end to be extra safe and plugged it in the same way each
time.

- For those with odd positive sync game board: This monitor only accepts
composite negative sync. You will need to get a hex inverter and a 5 volt
line and invert your old sync if you can't adjust it on the board in order
to get a picture. Many boards use negative separate (easily
combinable--just combine the wires) or negative composite, but some use
positive separate or composite and need adapting.

- There are 2 yoke jumper rows so if you mount the tube upside down, you can
easily flip the image 180 degrees by using the other jumper row..without
having to remount the tube or de/re-solder the yoke wires. (This is a common
problem with old vertical games that each rotated the tube differently.)
[Note: in practice I have seen some SLIGHT color shifting when a yoke is
flipped due to the way the beams hit the phosphor slightly differently, so
perfectionists may want to find the way to mount and control the yoke that
looks best and is the best adjustable with the pots.]

- For $73 shipped (for the 19" version), it's a pretty good deal if you have
a/many donor tube(s) and don't have the time, experience or want to spend
money fixing up broken or "untested" old chassis. However be aware it may
take some trial and error finding a 'perfect' match. If more people have
tried this and could report their results, along with tube model #'s we
could figure out which ones work better or worse given an individuals
tastes.

- Bad: I found that no matter how long I let the chassis sit unplugged
(admittedly 24 hours at most), it did NOT auto-discharge the tube, like both
of my K4600's and my G07 and my Sanyo EZ20's do. I was actually amazed at
this fact given new technology. I have NEVER gotten a "zap" when
discharging any of my old chassis+tubes before removing the anode cap.
However I got THREE healthy zaps in a row each and every time I discharged
each tube I swapped in and out of this chassis. The first zap jumped from
the clip to the screwdriver when they wern't even touching, the second and
third (after waiting a few secs) required touching the clip. Therefore
people 'used to' not getting zaps discharging will be in for a surprise if
you do a few swaps on this. Yes, ALWAYS ALWAYS ALWAYS assume there is a
charge and discharge three times, even if you don't hear/see anything after
the first time... you may have 'missed'.

- Good: The anode wire clip is VERY easy to clip in and remove. (Unlike the
horrible one in the WG K4600 that is very hard to work with, especially to
remove). This clip seems to stay very tight and any anode 'crackling' went
away shortly after turning on (a sign of a poor connection).


That's all for now... When I get time, I will post numerous photos of the
results of each tube on each chassis. Please reply (to the forum preferably
so it isn't lost in spam) with any comments on the review or your
experiences if you've tried them yourself.

-- Pac-Fan
 
S

Scott Caldwell

I'd like to see this, since I have several TV tubes I'd
like to start using. I've considered his tubes, and based
on what he asked to be measured, it seems like a fairly
easy tasks to mate the tubes with his respective new
chassis.

Scott C.

Pac-Fan said:
All --

This post is intended to be a summary (though it still got long) review of
Victor Genao's (8liners.com)'s replacement CGA/low-res analog RGB arcade
monitor chassis. A much more thorough review with numerous pictures and
explanations will be posted to a web site (anyone have space?) when time
permits.

If you have personally tried one of his chassis as well, please contact me
and confirm/contrast anything noted below. If you reply you MUST include the
word 'chassis' is the title otherwise your mail will be lost in the spam
deluge, or preferably post to the group.

I am not in anyway related to Victor or his company, just an enthusiast with
enough CRT background to be safe and to be able to try out numerous tubes on
a chassis over a couple evenings. All I have in this is $73 for the chassis,
shipped, plus some old donor tubes, and about 10 hours work (also doing
swaps in a WG arcade chassis). My review is intented to be fair and
impartial based upon MY experiences only. Yours may vary based upon tube and
yoke variations.

Remember: Safety first. Don't attempt this unless you know and understand
all risks of working with CRTs and high voltage.


Summary: A cheap, quick and easy way to make an arcade monitor with (nearly)
any old TV or Arcade tube with their yokes attached.

Results: Vary depending on donor tube type, brand, model, quality, previous
(ab)use, yoke characteristics and other factors. Overal very positive with a
few caveots.

Unit purchased: I purchased the "low impedence" version. Meant for use on
tubes with yokes with vertical windings measuring around 15 ohms DC voltage.
(Technically, yokes work and vary based upon impedence [AC resistance, not
DC] but that's another topic for another post) Low impedence versions are
similar to a Wells-Gardner K4600 series monitor NOT an Electrohome G07 which
is high impedence (~55 ohms, DC).

I have yet to find a TV set with a high impedence yoke that also has the
correct tube pinout. With 5 tubes total, plus testing a WG chassis too,
making for 10 combinations, I didn't want to get into swapping yokes for
"perfect" combinations leading me to do 100+ ? tests along with
reconvergence/etc.. :( The intent of these chassis is for a quick setup
with a tube and its existing yoke...

Overall comments, in no particular order (remember far more detail will be
posted later, with pictures)

- Original RCA 19VJTP22 tube + yoke from a WG K4600 presented a super sharp,
VERY highly focused pixel screen at nearly any (resonable) contrast and/or
brightness. As good or better than the K4600 it came from. However the yoke
suffered from pincushion on the horizontal left and right part of the tube,
bowing inward about an inch in the center making it annoying to use. No way
to adjust it out. (Tube had burn-in but looked good in the chassis with the
new picture on it.)

- 4 different donor TV tubes. A Matsushita dark-tint screen from a mid-80's
Quasar knob tune set (very very faint overall burn-in), 2 Orion tubes from
late 80's Emerson quartz mini-dial and PLL synth tune sets (different tube
model #s), and a Magnavox/NAP/Philips tube from an early 80's Magnavox knob
tune set. Other 3 tubes showed no visible general burn-in.

- All 4 tubes presented colors very well, except the dark tint one that
seemed to be somewhat 'gun worn', which makes sense given the light burn-in
and darker glass. Overall on the all 4, the colors were vibrant and very
adjustable. However all 4 tubes exhibited an overall blurriness that could
NOT be removed using the focus control, even though the edge of the focus
pot was never hit. The only way to get the clarity in each pixel to match
the original WG tube was to adjust the brightness control very low (too low
to place in a game however) At normal brightness levels, basically there
was significant "blooming" around the pixels, especially white, making it an
overall soft, yet, not out-of-focus image.

- All the drive controls, cut-offs, screen and focus were adjusted in every
way trying to 'fix' these problems. However, a bit of background told me it
wouldn't help. You see, I also tested each of these tubes in the WG K4600
chassis and all of them had nearly the same highly focused pixels on the WG
chassis (though they had yoke problems there, where they had outward bowing
pincussion, opposite of what the WG tube did on the 8liners chassis...which
makes sense). I also compared the sharpness against a NOS, basically
unused, Hantarex MTC9000 monitor I have that is brilliantly sharp at even
high contrast/brightness as a basline comparison. (No, I didn't want to swap
that tube in to test...yet)

- Two of the tubes (the dark Matsushita and the Maganvox tube) exhibited
slight pincushion in the lower right corner (assuming the anode cap was on
top for orientation). The horizontal lines were slightly drug towards the
corner in the corner, but it was not so annoying as to make it unplayable
like the large pincusion exhibited by the RCA/WG tube.

- Other than the slight bends noted above, the chassis seemed to handle a
wide variety (9.8 to 14.5 ohm DC vertical) yokes keeping the pictures
straight and only very light geometry issues, but the 8.5 ohm one from the
WG was apparently too different in impedence to work without pincushioning
(and vise versa--the TV yokes in the WG chassis all had pincushion due to
impedence mismatch)


Conclusions:
- Depending on your donor tube luck--If you are looking for a monitor to
present a nice smooth screen, especialy with newer games that have numerous
solid colors and large fonts, you probably will be very happy with the
results. For the MAMErs it will blow away any attempt to use NTSC composite
or Svideo on a standard TV set, it will be better

- If you have older games with not much background and very clean/concise
lines (pac-man, galaxian, etc..) and LIKE seeing very sharp (but round, not
computer crt 'square') pixels, then you may have to look longer for a better
matching tube and/or do a yoke swap to make things match best. (e.g. if my
old RCA tube didn't have bad burn in, I could just swap on any donor yoke
from a TV set and have a really really nice monitor for what I like--sharp
pixels)

- It seems to like the impedence of TV set yokes best, but I only had one
compatible arcade chassis/yoke to compare against so my test sample is
admittedly small.

- The chassis has a wide range of controls and isn't anywhere as limited as
a WG 46xx or EH G07 series chassis. You can control virtually everything
with pots, and there is a "small/medium/large" jumper block to gain even
more size if the HWIDTH and VSIZE controls don't give you enough or too much
size. Unlike many monitors there are THREE drive and THREE cutoff controls,
giving you full (and easy) control over RGB grey and white balancing, which
is good if the donor tube may have a weaker gun than the others. Focus seems
to be very wide..I didn't ever reach the 'edge' of the pot in either
direction when I switched tubes. I did run into that on the old WG chassis
where a donor tube would just be in focus at the extreme left or right of
the pot.

- Built in switch-mode isolation transformer is nice so you don't need a
huge heavy copper wound iso. It includes a very cheap line cord with AC end.
I was annoyed it was not keyed hot (small) and neutral (wide), as techically
it's safer to run the hot in through the fuse first and not the neutral. But
I just labeled the end to be extra safe and plugged it in the same way each
time.

- For those with odd positive sync game board: This monitor only accepts
composite negative sync. You will need to get a hex inverter and a 5 volt
line and invert your old sync if you can't adjust it on the board in order
to get a picture. Many boards use negative separate (easily
combinable--just combine the wires) or negative composite, but some use
positive separate or composite and need adapting.

- There are 2 yoke jumper rows so if you mount the tube upside down, you can
easily flip the image 180 degrees by using the other jumper row..without
having to remount the tube or de/re-solder the yoke wires. (This is a common
problem with old vertical games that each rotated the tube differently.)
[Note: in practice I have seen some SLIGHT color shifting when a yoke is
flipped due to the way the beams hit the phosphor slightly differently, so
perfectionists may want to find the way to mount and control the yoke that
looks best and is the best adjustable with the pots.]

- For $73 shipped (for the 19" version), it's a pretty good deal if you have
a/many donor tube(s) and don't have the time, experience or want to spend
money fixing up broken or "untested" old chassis. However be aware it may
take some trial and error finding a 'perfect' match. If more people have
tried this and could report their results, along with tube model #'s we
could figure out which ones work better or worse given an individuals
tastes.

- Bad: I found that no matter how long I let the chassis sit unplugged
(admittedly 24 hours at most), it did NOT auto-discharge the tube, like both
of my K4600's and my G07 and my Sanyo EZ20's do. I was actually amazed at
this fact given new technology. I have NEVER gotten a "zap" when
discharging any of my old chassis+tubes before removing the anode cap.
However I got THREE healthy zaps in a row each and every time I discharged
each tube I swapped in and out of this chassis. The first zap jumped from
the clip to the screwdriver when they wern't even touching, the second and
third (after waiting a few secs) required touching the clip. Therefore
people 'used to' not getting zaps discharging will be in for a surprise if
you do a few swaps on this. Yes, ALWAYS ALWAYS ALWAYS assume there is a
charge and discharge three times, even if you don't hear/see anything after
the first time... you may have 'missed'.

- Good: The anode wire clip is VERY easy to clip in and remove. (Unlike the
horrible one in the WG K4600 that is very hard to work with, especially to
remove). This clip seems to stay very tight and any anode 'crackling' went
away shortly after turning on (a sign of a poor connection).


That's all for now... When I get time, I will post numerous photos of the
results of each tube on each chassis. Please reply (to the forum preferably
so it isn't lost in spam) with any comments on the review or your
experiences if you've tried them yourself.

-- Pac-Fan
 
K

Ken Layton

Yes, it would be a nice idea to include screen shots of each donor
tubes' picture. Did you put a picture on this board with a monitor
pattern generator and/or just a video game board? Personally, I like
to use a monitor pattern generator first to get most of the focus,
screen, rough color balance, and rough picture centering/size stuff
out of the way. Then I use a Street Fighter II game board in the video
test mode to get fine color balance and razor sharp focus and screen
control adjusts to perfection. The SFII board has an excellent "stair
step" red-green-blue scale on screen that's perfect for color balance.
Does this new chassis have a "pincushion" control/adjustment on it? It
might be labeled "SPC" (Side Pincushion Correct). If not, then it may
be something that Victor may want to request be included in the
chassis from his chassis supplier in Taiwan.

One other important item to think about is for those reporting on what
donor tubes they tried is to include the yoke resistance, picture tube
number, AND the make & model of the tv set it came from. I really have
to applaud Victor's efforts to help bring affordable monitors to us
all in the game community. Not all of us can afford to go out and buy
brand new monitors all the time. He makes it easy for those who aren't
well-versed in monitor repair to do some work themselves and come out
with a working monitor.
 
P

Pac-Fan

Yes, I used an Arkanoid II Jamma board in regular and test mode. Test mode
produces a white cross hatch pattern and 16 squares, 4 gradiated shades each
of RGB and white. Perfect for color balancing, focus, screen and brightness
adjustments.

Admittedly I tuned it well for one tube and then left the drive controls the
same only slightly adjusting cutoffs for equal gun output when tubes were
switched. They were all about the same.

No, the new chassis doesn't have any pincushion control at all :( I don't
think any of the chassis that the company that Victor gets the chassis from
have pincushion control.. only additional features like remote cable for
pots, etc.. The OEM for it can be found here:
http://www.jenshinn.com.tw/j220.htm

Once I get all the pics and text together, I will have pictures of the donor
TV shells and model # info, plus all the other pertinent information.

I thought of another annoyance I didn't list last nite: The input pins are
non standard and therefore you must use the included wire and convert it to
the old style connectors as the pin size and spacing are nowhere similar
between the two.

Also, although most people wont run into this (as they won't be swapping
tubes multiple times), I found the spring on the ground strap to be very
tight and once stretched, it deformed and didn't recollapse to the original
size. Over time and multiple tubes it will loose tightness and won't
provide a good ground to the aquadag and will probably have to be zip-tie
assisted.

More info later or in response to your questions!

[snip]
 
B

Bill Maier

Hey all,

I purchased three high impedance chassis from 8 liners because I
had three dead or non-working GO7's.

First off I'd like to say I'm no monitor expert, but I have done
some cap kits, flybacks, transistors, etc. and am learning all the
time.

The first chassis I hooked up I mixed the vert and horiz and popped
a cap on the board. Do not do this. This is bad. I contacted Victor
and he said he would repair it for $20. I thought this was very nice,
since I was the one that let the smoke out.

The second chassis I installed correctly. The picture was very
nice and crisp, good color, good adjustment except the horiz width did
not work- just spun freely. The only problem was that the image was
bowed in about one inch on the left and the right (monitor mounted
horiz). Like this ) (. There is no adjustment for this I used this
chassis one all three tubes with the same results.

The third chassis was exactly the same as the second on all three
tubes.

I also have a known good GO7 chassis that I installed on all three
tubes that worked perfectly in every case.

However, my test game is a MAME machine running with a JPac. The
JPac has a video amplifier built in so I still question if this may be
the cause of the bowing.

When I have more time and a good canidate I'll test these chassis
in a regular game like my Ms. Pac. I attempted it in my Robotron but
there is no provision for it to sync to this game.

Apart from the bowing (which IMHO is intolerable) it's new, cheap,
and a time saving remedy for your 20 year old monitors. Perhaps one
of you monitor guru's out there may have a solution for this problem.
I am willing to provide one of my chassis as a test bed. So please
contact me if you are interested.

Thanks.

,Bill
 
P

Pac-Fan

[snip]
The first chassis I hooked up I mixed the vert and horiz and popped
a cap on the board. Do not do this. This is bad. I contacted Victor
and he said he would repair it for $20. I thought this was very nice,
since I was the one that let the smoke out.

Yes, that is very nice of Victor, but once you factor in shipping, it's
kinda pricey, especially since you said you've done cap kits, this should be
a 5 minute replacement and you should be able to pick up the cap from a TV
shop or even BobRoberts for not too much (or email me and I might have an
old one scavenged from old boards I could send you if you can tell me the
ratings/which one)

The second chassis I installed correctly. The picture was very
nice and crisp, good color, good adjustment except the horiz width did
not work- just spun freely. The only problem was that the image was
bowed in about one inch on the left and the right (monitor mounted
horiz). Like this ) (. There is no adjustment for this I used this
chassis one all three tubes with the same results.

This is EXACTLY what I experienced using the original RCA tube+yoke from a
WG K4600 on the 8liners chassis... It ended up with )( pincushion. [and that
was the low impedence chassis]. However with every donor TV tube+yoke, I
got near-perfectly [] square screens. And vise-versa... RCA tube+yoke in
the K4600 looked [] while every TV tube+yoke bowed outward () in the WG
chassis.

Therefore I believe that Victor's (Jenshinn) chassis' are tuned to work with
most standard TV tube yokes and NOT the old Wells-Gardner or Electrohome
chassis (at least those two).

It would be interesting to hear from others with these chassis and also
other chassis to see how the yokes interchange. However if I recall
correctly someone on ArcadeControls message boards tried this on a G07's
tube and didn't seem to have this problem, but it may have been swapped
previously with a different yoke for them?

As far as your sharpness.. were these old RCA 19VxxP22 tubes? I see so much
more sharpness on the old tube in the new chassis than I do on newer,
unburned in donor TV tubes at normal brightness/contrast levels. The
sharpness on the old tube comes close to a minty-new Hanatrex monitor I
have, where the 8liners chassis on a TV tube is just too 'bloomed' and soft,
but not really out of focus, but definitely not sharp.

However, my test game is a MAME machine running with a JPac. The
JPac has a video amplifier built in so I still question if this may be
the cause of the bowing.

This might be an issue, but unlikely since you can get it good on the
original chassis and it matches what I witnessed.


Anyone else care to post experiences?
 
B

Bill Maier

<<<<Yes, that is very nice of Victor, but once you factor in shipping,
it's
kinda pricey, especially since you said you've done cap kits, this
should be
a 5 minute replacement and you should be able to pick up the cap from
a TV
shop or even BobRoberts for not too much (or email me and I might have
an
old one scavenged from old boards I could send you if you can tell me
the
ratings/which one)>>>>

I did replace the failed cap. Although now the chassis does power
up, the screen is squished horizontally. I don't intend to pursue
this until it can be a usable chassis.

I believe this chassis would be a good solution if there were an
adjustment for the pincushioning. Perhaps a cap in that circuit with
a different rating?

C'mon, anyone have any advice? I've got three of these things
waiting to be used :)

,Bill
 
B

Bill Maier

One other thing that I forgot to mention. Any game with a bright
screen the monitor would dim immediatley. For example- Stargate demo
screen when all of the colors flash, the screen would dim and then
resume. QBert's blue background would dim to near black. And if
running windows the mame32 screen would be unreadable. However, I
don't know if this effect would exist in a standard arcade game since
I was testing on a mame machine with JPac.

,Bill
 
K

Ken Layton

It would be helpful if a service manual and schematic were available
for the replacement chassis. Then we could see about a pincushion
correction circuit.
 
M

Mark Allender

I used one of his high impedence chassis to drive what I _believe_ was a
tube from a Sanyo 20-EZ (the chassis was hosed, but as I said, I'm not even
sure that the tube from from the Sanyo since it was mounted in a Frogger. I
suppose that chances are it was a Sanyo tube though).

I have had _no_ issues with the replacement chassis. Colors look fine to
me, no pincushioning that others have spoke of. It's been easy to adjust
the colors, size, and placement of the image.

I do have a modern flat screen TV tube that I'm going to try one on
sometime.
 
B

Bill Maier

Okay, I emailed Victor and he's going to send me a copy of the schematics.

Again, I will offer one of my new chassis for experimentation.

Is there anybody interested in this project? It's way beyond my skills.

,Bill
 
P

Pac-Fan

FYI: For pictures comparing the quality of the 8Liners chassis on 5
different picture tubes (4 salvaged from 1980's TV sets and 1 original RCA
from a WG-K4600) check out the following site:

http://www.oscarcontrols.com/chassis

(Disclaimer: Oscar Controls has no part in the review, they are simply
providing the web space)

That web page accompanies a post made in the newsgroups a few months ago
titled: "Tech Review: Victor's (8liners/Genao) Replacement Arcade RGB
Monitor Chassis (LONG) "

http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&[email protected]


Pac-Fan said:
All --

This post is intended to be a summary (though it still got long) review of
Victor Genao's (8liners.com)'s replacement CGA/low-res analog RGB arcade
monitor chassis. A much more thorough review with numerous pictures and
explanations will be posted to a web site (anyone have space?) when time
permits.

[snip]
 
B

Bill Maier

Victor has sent me the schematics for this chassis. If anyone wants
to tackle the blooming and pincushioning problems let me know. I'll
provide the schematics and the chassis.

Thanks.

, Bill
 
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