Problems with an Apple II clone named "Pluto", no color

31 posts / 0 new
Last post
z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Problems with an Apple II clone named "Pluto", no color

My Apple II clone "Pluto" (which has its origin in germany) does not like to show up colors on a color monitor.
It has a PAL Encoder card in Slot #7, and my Monitor is also a PAL capable display (Commodore 1084, tested with other devices and is able to show up colors).
I have the possibility to use two video outputs, one comes directly from the PAL encoder card, the other from the board.
The picture from the PAL encoder card shows up less sharp lines (a bit shadow too) and a bit "grainy", but has different grey levels.
The picture from the board looks sharp and the grey levels are less different (more intensive, but less differentiated).

I already tried to turn the small variable capacitor, no effect.
There are some variable resistants (potentiometer) but I didn't tried them to change, also because I was not able to reach them while running the computer (have to pull out the card).

Are there any manuals or schematics available for the PAL encoder card ?

Is there any chance to use also RGB output but just with this card (and no special adapter) ?
Or at least Chroma + Luma (like SVHS) instead of (bad) composite video ?

gsmcten's picture
Offline
Last seen: 6 years 4 months ago
Joined: Oct 4 2005 - 18:52
Posts: 2629
Re: Problems with an Apple II clone named "Pluto", no color

z80eu,

What you need is help of a Higher Order...

Look! Up in the sky! It's some Birds! No, it's two Planes, No, its

SpeedyG and BillO!

While you are waiting for them though you can
go to the upper right corner to where the Search Box is located and plug in
one or two search parameters. You may be surprised at what has already been written on your subject.

By the way... WELCOME!!!!

Steven Smile

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

I've tried already "Search", thanks.
Unfortunately if you're looking for "PAL Encoder" there are not really many entries found.
I didn't found any manual nor schematic for the "PAL Encoder" (e.g. at ftp.apple.asimov.net, or at apple2online.com), I didn't looked through all third party Apple II books, but looked for PDFs about "PAL Encoder".
At the moment, I'm unsure if it's only a matter of "right configuration" or if there is a real fault hidden (but I guess it's a faulty chip).
So gathering infos about the PAL encoder card will be Priority 1, but then it may come to a search for hardware problems.

Thx for welcome me. I already tried to look in other forums, but this one should be the best for getting qualified help Wink

stynx's picture
Offline
Last seen: 6 hours 6 min ago
Joined: Apr 19 2012 - 09:41
Posts: 223
Re: Problems with an Apple II clone named "Pluto", no color

There were several types of pal encoder cards from several manufacturers. well known german manufacturers are Basis and IBS. If your card has something written on it, you should either show a picture of the card (front+back) or tell exactly what you see.

-Jonas

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color

Hello z80eu,
i guess you got advice from stynx to take a chance here....
i have viewed the other thread with the pictures and passed over a list to stynx to pass it to you:
-------------------------------------------------------------
"Hallo Jonas,
Aus dem Forumseinträgen gehen einige Punkte nicht klar hervor:
1. Von wo, hat er sein Videosignal abgegriffen ?
2. Welche Karte verwendet er wirklich ?
3. Von wo auf dieser Karte greift er sein Signal ab ?
4.Welches Rev. ist der Apple bzw. clone ( ein gutes Foto 3500 pixel x 2400 pixel
obere Hälfte des Boards ohne Karten ) ?
Von diesen Details fehlen gute Foto´s.....
Immerhin:
Man sollte wissen, ob das Mainboard ein Colorkiller circuit besitzt
oder nicht und ob er korrekt funktioniert....
eventuell ist der 'Colortrimmer ( Trimkapazität auf dem Mainboard )
falsch getrimmt ?
wenn er das Signal beim Hilfsabgriff ( 4 Pfosten ) aufnimmt ist auch
die Frage auf welchem Pegel er das Signal mit dem Trimpoti eingestellt
hat ( wegen korrektem detect des Sync )
und bei der Karte tauchen ebenso viele Fragen auf....
kurze Anmerkung zu den Texten im Forum:
Die Apple PAL-karte nutzt zur Decodierung einen TCA650, wohingegen die
IBSkarte zur Decodierung den LM 1889 verwendet.
Der 1889 nimmt eine vollständige RGB Decodierung vor, so dass an den Pins
jeweils die vollständig separierten Signale vorliegen wohingegen der
TCA650 bei Apple lediglich eine "Teil-decodierung" vornimmt ( also sync
und vsync extrahiert ) und der rest wird mit Logikchips und
analoger elektronik ( durch shifting und shutter technik ) bestimmt
und durch den Fensterdiskriminator getriggert. Der TCA650 ist eigentlich
nur ein Chip zur Konvertierung zwischen NTSC, PAL und SECAM nicht aber
zur Decodierung des RGB Signals...

Eventuell verweist Du ihn an mich, wenn er bessere Fotos macht und die
obigen Details genauer erklärt.....
-----------------------------------------------------------------------------
but in advance we´d keep here along with english language to permit
the other members to follow up the postings....
within the helppages related to creating new content there is rather good info
about integration of pictures to the postings or adding links to the pictures....

The moment i have more info´s by the provided pictures i´ll continue the troubleshooting...

welcome here
besides at the moment i´m currently heading for my pillow....
but this gives more time to take pictures and i´ll be back tommorow morning
while sipping my morning cup of coffee....

sincerely speedyG

BillO's picture
Offline
Last seen: 4 years 5 months ago
Joined: Jun 20 2014 - 18:03
Posts: 258
Re: Problems with an Apple II clone named "Pluto", no color

z80eu,

What you need is help of a Higher Order...

Look! Up in the sky! It's some Birds! No, it's two Planes, No, its

SpeedyG and BillO!

Okay, it seems I've over stepped the bounds here in some way. However, I did not think I was that verbose.

In any case, my humble advice would be to (depending on the version of the 1084):

Look first at changing the CVBS/LCA switch and the VCR switch.

Then look to the cable or termination of the cable. Is the cable the right impedance? Or does the RGB board measure the correct resistance? How about the monitor itself? Look for 75 ohms in all cases.

I am not saying that these are the problem, but just that they could cause the problem and they are easy to check. Then you can see if the encoder chip has gone wonky.

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color

Hello Bill,
the list you published is quite well....

unfortunatly i have forgotten to mention the previous part of the thread at the other forum:
http://forum.classic-computing.de/index.php?page=Thread&threadID=6872&highlight=

the picture of the computer itself published in the second posting of that forum is in several areas rather blurry
and i have not been able to realy check the used entire path of combined components....

- in fact the one used and mentioned green cable does not look very reliable......

the only picture really clear is the one published from the IBS RGB Card..... but that seems
not to be the one realy used in the computer but rater more a picture snatched from other source.

And for better diagnostic it would be usefull to get better views to the
"cable jungle area" between the slot 7 and the case.....

it seems that in fact besides the wild cables and the IBS RGB card also the nearly simple
cloning of the UHF Mudule of the Sup´r Mod RF Output is involved too.....

and the clone boards of the Apple have been known to clone the rev.4 mainboard as well as the rev.7
and the RFI - but this picture does not display enough to enable correct identification....

so that were the points i spotted out to Stynx, when he spotted me to that thread...
and therefor i just repeated that previous part of the alternating contact of the german mailing above....

sincerely speedyG

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

Please give me some hours to make pictures also from the PAL encoder card and the mainboard, I have to disassemble a lot before I can do this.
Meanwhile you can take a look at the computer from (mostly) outside in my blog from z80.eu.

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

Unfortunately I am not able to attach images here (no possibility while commenting seen):

Instead, I will link to my own site:
PAL Encoder Front
PAL Encoder Back
Mainboard total
Mainboard back/upper part
Mainboard front/lower part
Mainboard Slot7 area

Note: I can't remove the PAL encoder card because of many wires connected to the board directly.

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color

Hello z80eu,
thanks for taking the pictures .... this will help with analysis ahead...
but there are still 2 or 3 pictures missing:
1 picture with cables running towards the UHF-Modulator ( the silver box at the very right side at the case )
1 picture with the connectors of the cables and the rearside view ( i guess from the UHF Modulator there is at the backside also a chinchplugconnector )
and a highresolution picture of the very fast first picture displayed in the other thread without blur and the cables leaving the case at the rearside
to the pulgs outside.....
in meantime i´ll start making a drawing of the base shematic functions of the related parts interacting with each other and their function with additional explenations....
sincerely sopeedyG

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

A picture from rear view will not help, really nothing to see except the RF connector from the UHF modulator, the cassette interface DIN 5-pin jack (lower one) and also a video connector DIN 5-pin jack (upper one). The original Apple II+ connectors are not there.
Modulator and video connector (upper one)
The DIN 5-pin jack for video is not really a secret, because there is only the red wire on one pin which "carries" the signal, 2 additional pins are connected to ground, but no other pins are used.

I will try to turn the variable capacitor on the mainboard also (named "COLOR" on the board), although it's for the original NTSC signal I guess.

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color

At this state i do not believe the trimming of the capacity will bring us ahead to a solution....
I have detected other problems which must be solveed previously....
the reason for my demand to the pictures is sorting out the cables and functions of the "wild bunch"
reducing the diagnosis to the cables realy needed and ordering the purpose of cables
not beeing able to be assorted at the moment because they are not ending in limits of the pictures at the moment....
please also check pm sent to you here....
sincerely speedyG

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color

Hello Z80eu,

after sorting the info´s i´ve prepared a set of pictures resulting from your pictures
and making a kind of overview table.

Therefor i´d recommend to download the 9 pictures ( pic01 to pic08 and the overview table picall )
and working along step by step.

the RGB card is a kind of clone of the Apple RGB card although several parts are different from
the original
. The original uses the 7M signal from the slot. So the red wire from the 74LS86 pin 8
that brings the 14M signal to the card is not normal common copy of the original.
This connection therefor is doubtful to be correct..... but at the moment this might be kept.
In later part of the text there is further explenation.

The links to the downloadable pictures:

http://www.appleii-box.de/Bilder/pic01.jpg
http://www.appleii-box.de/Bilder/pic02.jpg
http://www.appleii-box.de/Bilder/pic03.jpg
http://www.appleii-box.de/Bilder/pic04.jpg
http://www.appleii-box.de/Bilder/pic05.jpg
http://www.appleii-box.de/Bilder/pic06.jpg
http://www.appleii-box.de/Bilder/pic07.jpg
http://www.appleii-box.de/Bilder/pic08.jpg
http://www.appleii-box.de/Bilder/picall.jpg

IMAGE(http://www.appleii-box.de/Bilder/picall.jpg)

pic01:

Under normal conditions the 14M signal is not required but due to missing docs about
the card we´ll leave this point at the moment the way it is....

But the unshielded wire from 74LS86 isn´t that good and dampens signal in the mainboard....
In the original Apple the 14M signal is leading to the pin 24 at the componentside
only at slot 7 and the videocard should have no connection to pin 27 !
Otherwise there is a shortcut with the DMA channel of the lower slots 6 and previous slots !

Its therefor a good idea to examine the pin 24 at component side and inspect if the 14M signal
is present there at the slot 7 with a scope! (*)

If 14M signal is demanded by the card its in such case better to pick the signal from
that point instead of dragging that signal accross the entire mainboard with the
red cable !

Its also good idea to inspect / follow that trace from pin 24 of the slot along the mainboard ...
maybe there is similar to the original Apple mainboard at some point of that trace a kind of "soldering pads"
that must be connected with a drop of soldering material to get the signal from pin 8 of the
74LS86 provided to pin 24 of the slot 7 !

And it´s also recommended to check, if there is a trace from the point where the red cable is soldered
at the soldering side of the RGB card to pin 24 at the slotpads of the card.
If there is a chance to get the signal from the 74LS86 to pin 24 of the sot 7 and
a connection from the soldering point of the pin 24 of the card, you can remove the red wire and
get rid of that cable, reducing possible trouble or malfunction !

(*) when inspecting pin 24 with the scope it´s also good idea to examine pin 19 at the component side
to see if the sync signal is availiable there and to examine if the trace leading to that pin is
interrupted at a point with soldering pads that must be "activated" by adding a drop of
soldering lead to the pads.
Similar examination should be performed at the soldering side at pin 35 to see if there is a
color-ref signal availiable ! The color-ref signal is also availiable at pin 3 of the 74LS02 at
location A14 or at pin 2 of the 74LS02 at location B13 or better the pin 3 of the 74LS175 at location B1 !
In some cases it turns out to be usefull to replace the 74LS175 by a faster 74F175.

pic 02 and pic 03:
It´s quite common that the memsignal is picked from the pin 5 of the 74LS259 at location F14.
In this computer that signal is picked by the blue wire. some 80col cards like the videx also
pick off that signal. In later part of the text we will reach a point
that you might examine if the card will work without the use of the blue cable !

A real problem now is discussed:
At nearly all cards except those that realy use the INT and DMA signals from the CPU the card
have internal shortcut from pin 27 to pin 24
and from pin 28 to pin 23.In this computer RGB card a wire is soldered to pin 28 at soldering side ( pink wire )
and pin 23 ( blue wire ) at component side and i´m quite sure this to be a shortcut and mistake !

pic06:
The pink wire here to pin 28 is rather sure a mistake ! That wire contains the videosignal from
the auxiliary videoconnector of the mainboard ! And it surely is not to be shortcut with the blue wire !

In general if system has no RGB card inserted that signal at the pink wire is directed to the video input of the UHF Modulator.
From there the signal is directed then from the output of the UHF Modulator to the TV-set and the TV is
adjusted to the channel displaying the signal of the Apple. Under regular conditions that signal is located
at a channel between channel 34 and channel 39 of the UHF band of the TV.
The hole in the Modulator is used for adjusting the channel of the TV and it also might be used for adjusting best signal at the TV-set with sharpness and precise colordisplay at the TV.

At the TCA650 of the card that videosignal should also be present at pin 1
of the TCA650. In some special cases that FBAS Videosignal is instead directed to pin 3 of the TCA650.
But it may be directed to only one of that pins at the TCA650 either pin 1 or pin 3 !
At the moment i can´´t detect any other position where the FBAS Video signal may be inserted to the card except the points mentioned in the previous text !

Another problem to recognize:
There have been 2 kinds of UHF Modulators in those days in the marketplace....
a simple one only capable to handle black/white signal to TV-sets
and a more expensive one capable to handle color signal to TV sets.
Unfortunatly it seems that the top side of this UHF Modulator is fixed by glue to the case
so that the topside of that module can´t be examined anymore.... otherwise it would have been
possible to view the label and inspect which kind of module has been used in this computer.

But if you don´t pick the videosignal off from the card and take it instead from the auxiliary mainboard video connector
to the module input and connect the module output to the antenna input of the TV set and tune in the correct channel
of the module at the TV, it might be possible to at least detect if that module is able to handle color signal.

picall:
In this sheamtic i display the ability to insert a switch that enables you to switch between the output
of the card and the output of the mainboard to direct the signal to the UHF Modulator and chose one of
the signals. I´d recommend to use at the end of the auxiliary video mainboard connector pins a fitting
pin plug to keep the connection removable. And at the card i´d replace at the points the cables are
soldered at instead massive pins and also use removable pin connector to also keep this connection removable.

At the switch the wires may be soldered. And additional i´d recommend to use shielded 70 Ohm core thin
antennacables
and connect the shielding at one end ( preferably at the end of the switch ) to ground.

Be carfull in that case to keep shielding away from the corewire and avoid any kind of shortcuts !

Best behaviour will be to secure both ends with shrinking hose!

After woorking along this list it would be good to place here a feedback of the results and then - if needed we can continue procedures.

sincerely speedyG

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

Thanks really a LOT.

What I do not understand - the blue wire starts at Pin 4 of the LS259, not Pin 5.
See http://www.z80.eu/images/pluto_blue_wire_ls259.jpg ...

The Blue wire ends at Pin 23 of the slot, right.
Why is Slot Pin 28 and Slot Pin 23 connected together ?

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color

If it is pin 4 and not pin 5 the blue cable contains the switching signal of "text Mode".
Even that signal may not be short cutted with the B8 ( location ) pin 2.
It´s even then a mistake.
the wrong detection of the pin at the 74LS259 just was result of the picture you made and the
angle of view it was taken..... anyhow the use of the blue wire will be explained later more....
at the moment the statemants made to the blue wire not bothering if it was extracting signal from pin 4 or pin 5 are still valid.

The so called INTin and INT out
as well as the DMAin and DMAout
are a kind of "Daisychain" running along all slots.
If any card accesses the INT or DMA channel of the CPU it interupts the access of the remaining cards in the other slots to avoid conflicts.
Therefore at that cards, which do not use this Channel the contacts are schortcut by a contact-through punch which contacts both sides of the daisy chain disableing access from that card.

And even if the pins are not contacted through there still is a possible conflict remaining with the blue wire because in case the B8 pin 2 is directed to the slot at pin 23 like at the original Apple II it will cause problems.

B8 pin 2 is 74LS174 and contains part of the softswitch to "Hires" signal

speedyG

Offline
Last seen: 8 years 10 months ago
Joined: Jun 15 2014 - 12:48
Posts: 305
Re: Problems with an Apple II clone named "Pluto", no color

There have been 2 kinds of UHF Modulators in those days in the marketplace....
a simple one only capable to handle black/white signal to TV-sets
and a more expensive one capable to handle color signal to TV sets.
speedyG

Just wondering wonder why would a modulator intentionally kill the colour sub-carrier (in this case 4.43MHz) when it lies in the composite videosignal's bandwidth?
I would never suggest using a modulator for apple 2 in the 21st century...
Despite there is no picture of the computer mobo provided the topic starter mentioned that it has a PAL color output on the motherboard and it also outputs in b/w. I would have started by checking the COLORREF signal presence on slot 7...

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color


Just wondering wonder why would a modulator intentionally kill the colour sub-carrier (in this case 4.43MHz) when it lies in the composite videosignal's bandwidth?
I would never suggest using a modulator for apple 2 in the 21st century...
Despite there is no picture of the computer mobo provided the topic starter mentioned that it has a PAL color output on the motherboard and it also outputs in b/w. I would have started by checking the COLORREF signal presence on slot 7...

barking at this tree will be ignored.... answer was given in thread:
http://www.applefritter.com/content/laughable?page=23#comment-73866
posting #1177
speedyG

Offline
Last seen: 8 years 10 months ago
Joined: Jun 15 2014 - 12:48
Posts: 305
Re: Problems with an Apple II clone named "Pluto", no color

The simpler the rf modulator (for example one transistor modulators without intentional filters) the higher the chances that it does not cut color sub-carrier frequency.

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

I never planned to use the RF modulator, any consideration about it would be irrelevant.
My problem with that clone is related with the composite signal. I just like to get a color picture on my Commodore 1084 (and yes, I know how to use the 1084 with his switches/connections).

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

@SpeedyG: I have looked for an explanation about Int In and Int Out (daisy chained interrupt).
At http://fjkraan.home.xs4all.nl/comp/apple2faq/a2pin.html the follow is stated:

Pin 23 – INT OUT – Interrupt priority daisy-chain output. Usually
connected to pin 28 (INT IN). Note: On slot 7 ONLY, this pin can be
connected to the graphics-mode signal GR (Not available on revision A
boards).

Here Slot #7 is mentioned as an exception. Do you know something about the "graphics-mode signal GR" in conjunction with the PAL Encoder card ?

And btw. the picture of a similar PAL Encoder card http://jesperalsed.com/vintageapple/wp-content/uploads/2013/11/PAL-encoder.jpg does not have any connections to Pin 23 and Pin 28 ... strange.

Offline
Last seen: 8 years 10 months ago
Joined: Jun 15 2014 - 12:48
Posts: 305
Re: Problems with an Apple II clone named "Pluto", no color

Yes, /GR signal is present at slot 7 and is used by PAL and RGB cards to properly display text. Daisy chaining is NOT required for such cards at slot 7. A nice schematic of a PAL module can be seen on page 8-18 in Jim Sather's Understanding the Apple IIe book.

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

I already told you (at vintage-computer.com) that I am not looking for a general description how the Highres Graphics picture is generated ( http://www.z80.eu/downloads/understanding%20the%20apple%20ii-214-216.pdf ), I need a description how the PAL signals are generated, with an Apple II+ (not IIe) and with a PAL Encoder card.

Offline
Last seen: 8 years 10 months ago
Joined: Jun 15 2014 - 12:48
Posts: 305
Re: Problems with an Apple II clone named "Pluto", no color

The card versions are almost identical for //e and ][+, therefore you can use the schematics of the PAL module in that book , especially to figure out what is the problem with your card, but I do recommend you to try it first in another unmodified computer as I told you on the other forum.

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color

The basic difference is a question of timing, shifting and delay....
the decoding of NTSC, PAL and SECAM are defined by the timingdiffeneces/delays of the signal related to the triggers and sync signals.... so it´s very important to keep eyemark to the source of the used clocking and resulting "phase shifting"
from delays within the signalpath...

speedyG

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

@georgel: I guess it's not really difficult to understand - even for you - that I was interested in solving the problem for my parts (II+, PAL Encoder) and not for other parts (IIe, NTSC).
Again... in the book you mentioned at Page 8-18 and the next two pages the word "PAL" wasn't used. My referenced PDF file is searchable (text, not an image), therefore try to search for "PAL".

Offline
Last seen: 8 years 10 months ago
Joined: Jun 15 2014 - 12:48
Posts: 305
Re: Problems with an Apple II clone named "Pluto", no color

I have a scanned copy of that book and therefore cannot search for a text in it. In the real book (or in the scanned one) there is a schematics of the PAL module on that page. Here is the link again to the book http://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Books/Jim%20Sather%20-%20Understanding%20the%20Apple%20IIe.pdf

Look in the book for //e. You are searching in the different book, e.g. in the previous book for ][.

In order to solve your problem first you have to determine whether your card is faulty or your apple clone, or both. That's why I suggested testing the card in another unmodified apple.

speedyG's picture
Offline
Last seen: 5 years 6 months ago
Joined: Nov 16 2011 - 07:45
Posts: 2493
Re: Problems with an Apple II clone named "Pluto", no color

just adding the norm of both standards see here:
http://www.diffen.com/difference/NTSC_vs_PAL

and for basic explenation about the topic here:
http://en.wikipedia.org/wiki/Television_standards_conversion
and related to the stuff here see the part about phase correlation...

the trick is performed in the line Apple II ( U.S.Version=MTSC european version=PAL )
at the IIe in the HAL-chip by changing the timing of the clocking rates

at the Apple II the card solves the problem by delay / shift of the timing signals

speedyG

Offline
Last seen: 8 years 10 months ago
Joined: Jun 15 2014 - 12:48
Posts: 305
Re: Problems with an Apple II clone named "Pluto", no color

As I have said the PAL cards intended to work in //e will work in ][ and vice versa with wrong colors but they still would provide color picture (taking into account that the frame frequency should be 50 Hz, e.g. so called "euroapple")! The principle is the same. Every card could be modified to work in //e or ][ but this is out of scope right now. As you said there is no color at all with this PAL card in this computer. First you have to be sure that your computer it is set for 50Hz frame rate. You could easily differentiate 60Hz from 50Hz vertical sync pulses in the composite videosignal with an oscilloscope.

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

Because I do not like to discuss this further, please focus all the discussions to the topic, my Apple II+ clone and my PAL Encoder card. I do not want to rebuild an Apple IIe, nor I want to write a book about generating video signals in general. Instead, I am only interested in getting a color picture on my 1084 monitor.

Meanwhile I know why you do not stop to refer to that book from Jim Sather. See here: http://www.z80.eu/images/Difference%20between%20NTSC%20and%20PAL%20Apples.png
But they also mention that Sather do not explain in detail the differences between component and slot layout of II+ and IIe. So I am still looking for an original description of that PAL Encoder card.

P.S.: Yes, I even found in the "non IIe" book of Jim Sather a short chapter about PAL (not named PAL, but "Eurapple scanning") - see here: http://www.z80.eu/downloads/understanding%20the%20apple%20ii-210.pdf . But even this does not help figuring out the right wiring or what's going wrong in my special case, described and photographed above. Thank you for your understanding that I do not like to get this thread hijacked for a religious war about generating video signals.

P.P.S.: I have a real powerful OCR software so it would be no problem to rebuild the PDF in that way, that it will be searchable. But that can be discussed in another thread, not this one.

Offline
Last seen: 8 years 10 months ago
Joined: Jun 15 2014 - 12:48
Posts: 305
Re: Problems with an Apple II clone named "Pluto", no color

Okay, obviously I have to describe it that simple way:

1. Is your pluto set to 50 Hz veritcal sync? If not (e.g. it is set to 60Hz) try the NTSC color output of the computer itself on an NTSC monitor. At this point you might consider adjusting the trimming capacitor on the mainboard. If still no color go to step 2.
2. Set your pluto to 50Hz. Consult Jim Sather's book on how to do that.
3. Look for PAL color picture from your PAL card. At this point you might consider adjusting the trimming capacitor on the PAL card. If still no color picture go to step 4.
4. Does your card work in another eurapple? If yes go to step 5. Else will focus later on the PAL card itself.
5. Does your pluto provide specific signals to slot 7, e.g. 3.58MHz COLOR REF (pin 35), SYNC (pin 19)and GR (pin 23)? If not consult Jim Sather's book on how provide them to slot7 or if they are already wired fix the failing components on the motherboard.

z80eu's picture
Offline
Last seen: 9 years 10 months ago
Joined: Oct 30 2014 - 18:10
Posts: 13
Re: Problems with an Apple II clone named "Pluto", no color

I have tried to turn both trimming capacitors - the one named "COLOR" on the mainboard and the one which is found on the PAL Encoder card. As usual, it didn't helped because it would be too easy.
What do you mean with "set to 50 Hz" ... it was buyed and operated in Germany, so it should be obvious it is set to 50Hz (ok, will check it, but it should be as mentioned 50Hz, why not...).
And no, I have no other Apple II Europlus (that was indeed my first thought, to test components/cards on a second one.... no second one, no test).
In the moment my Oscilloscope does not have a "probe cable", and if I would buy one again, I have no idea with what picture (on the scope screen) I have to compare...

@SpeedyG: I've found a schematic for the PAL [Encoder] Card (with the help of one user of the classic-computing forum): http://john.ccac.rwth-aachen.de:8000/patrick/data/PALcard.pdf
If you take a look into it, you will see also what input signals are used (/text for example, see above also, LS259 Pin 4). May be now it can be better compared to my weird wires Wink

Log in or register to post comments