CHELCO 1983 600XL REV 3

[JGRAHAM2]

I have a rather unusual 600XL with a CHELCO 1983 600XL REV 3 motherboard. It also seems to have some mods to the board and the RF shield. See the pictures. Does anyone have an idea why these were done? The holes in the lower shield make no sense.

 

 

Edited November 6, 2021 by JGRAHAM2
Change shield picture

[JGRAHAM2]

Looks like the long red wire going to the PBI is to bring 5V to 47/48. I guess this model was not designed for the RAM expansion, so they added it.

[JGRAHAM2]

Looks like the long red wire going to the PBI is to bring 5V to 47/48. I guess this model was not designed for the RAM expansion, so they added it. Also, the holes make more sense when placed on the bottom case. Still, they seem an afterthought.

[+kheller2]

Early working version of the 600XL.  I’ve only ever seen pictures of one other one like this, and I think with a different power switch (slide vs rocker).   Do you have a pic of the bottom sticker?

[JGRAHAM2]

7 hours ago, kheller2 said:

   Do you have a pic of the bottom sticker?

Here it is

[bfollowell]

8 hours ago, kheller2 said:

Early working version of the 600XL.  I’ve only ever seen pictures of one other one like this, and I think with a different power switch (slide vs rocker).   Do you have a pic of the bottom sticker?

 

No, that one has a rocker; I'm fairy certain they all do. The power switch is on the far left edge of the motherboard in this picture. The slide you see is the channel select switch.

 

I have the same, or at least a similar model 600XL. Mine is also a Chelco unit and has the dark gray sticker on the bottom like that.

 

That obviously isn't an NTSC model, and mine is, so there are obviously some differences.

 

Edited November 7, 2021 by bfollowell

[flashjazzcat]

That's one very sweet board.

[+kheller2]

2 hours ago, bfollowell said:

 

No, that one has a rocker; I'm fairy certain they all do. The power switch is on the far left edge of the motherboard in this picture. The slide you see is the channel select switch.

 

Disagree. I know the one shown in this thread has a rocker, but as mentioned here: 

slide power switch.  

 

And the images of the other unit with slide here: http://www.atari.org.pl/forum/viewtopic.php?id=12054

 

The most popular CHELCO board is Chelco 1983 P/N: 150600008 REV 8A 600XL.   So, there were a lot of differences between 3 and 8A I would imagine. The trace layout on the 600XL is mostly the same except on this REV3.  Most folks would have a "A" or "X9A" or "X9B" board variant. 

 

The FAQ states there were three manufacturers:

 

"The 600XL was made by Chelco Sound (Hong Kong) Limited from July to December
1983 (NTSC units with "black label" 7YJ serial numbers), by Atari-Wong Co. in
Hong Kong from September 1983 to April 1984 (most NTSC and all PAL units), and
by Atari Taiwan Manufacturing Corp. (ATMC) from July to September 1984 (NTSC
units).  There were also some units assembled at ATMC in July 1985 (NTSC),
apparently factory-refurbished from stock originally manufactured earlier."

 

It must be a very interesting story how the layout changed so much to basically resemble the 800XL.

 

[bfollowell]

1 hour ago, kheller2 said:

Disagree. I know the one shown in this thread has a rocker, but as mentioned here: 

slide power switch.  

 

And the images of the other unit with slide here: http://www.atari.org.pl/forum/viewtopic.php?id=12054

 

The most popular CHELCO board is Chelco 1983 P/N: 150600008 REV 8A 600XL.   So, there were a lot of differences between 3 and 8A I would imagine. The trace layout on the 600XL is mostly the same except on this REV3.  Most folks would have a "A" or "X9A" or "X9B" board variant. 

 

 

I had no idea slide switches were common. I think they must have been more common in non-NTSC countries. I've never seen a U.S. model that had anything other than the normal XL rocker switch. I guess that doesn't mean that they didn't exist, but I'd think they must've been fairly rare. Are you aware of any U.S. models that had the slide power switch?

 

I need to look my board over for the numbers and try to determine which board revision I have. Thanks for the link. I'll have to read through that thread later.

 

EDIT:

I looked at my board and it is a Chelco 1983 P/N: 150600008 REV 8A 600XL, which you're saying is the most popular board, and by that, I'm assuming you mean the most common.

 

Edited November 7, 2021 by bfollowell

[manterola]

What is also interesting is the type iv keyboard with smooth keycaps variant. I guess these keycaps where used in the early releases of type iv keyboard. 

 

[JGRAHAM2]

Other things to note

- the keyboard uses the 800XL style ribbon and connector

- the bodge wires on the switch (perhaps to use the rocker vs slider?)

- no traces or through holes for a monitor jack where the channel select switch is (no easy UAV install on this one!)

- why the bodge wires going under the cartridge port? Other pictures I’ve seen of this model don’t include those.

- the 28 pin socket for the BASIC ROM. The ROM itself is 24pin… Reminds me of some 1200XLs.

[+kheller2]

1 hour ago, manterola said:

What is also interesting is the type iv keyboard with smooth keycaps variant. I guess these keycaps where used in the early releases of type iv keyboard. 

 

We’ve seen a few of these smooth key caps recently popping up. I would love a set. 

 

 

35 minutes ago, JGRAHAM2 said:

Other things to note

- the keyboard uses the 800XL style ribbon and connector

- the bodge wires on the switch (perhaps to use the rocker vs slider?)

- no traces or through holes for a monitor jack where the channel select switch is (no easy UAV install on this one!)

- why the bodge wires going under the cartridge port? Other pictures I’ve seen of this model don’t include those.

- the 28 pin socket for the BASIC ROM. The ROM itself is 24pin… Reminds me of some 1200XLs.

 

I’m curious about the RAM wiring if it’s easier to go 64K.   Take the cart port off and see where they go. 
 

1 hour ago, bfollowell said:

 

I had no idea slide switches were common. I think they must have been more common in non-NTSC countries. I've never seen a U.S. model that had anything other than the normal XL rocker switch. I guess that doesn't mean that they didn't exist, but I'd think they must've been fairly rare. Are you aware of any U.S. models that had the slide power switch?

EDIT:

I looked at my board and it is a Chelco 1983 P/N: 150600008 REV 8A 600XL, which you're saying is the most popular board, and by that, I'm assuming you mean the most common.

 

 

I don’t think the slide is common at all.  I don’t think rev3 is common.  But who knows anymore. I’ve only ever heard this rev 3 discussed three times.  (Makes me wonder what’s inside the 800XL sample that showed up here a few months back). 
 

and yes by popular I mean common, at least for CHELCO made 600XLs.  
 

 

[+kheller2]

6 hours ago, JGRAHAM2 said:

Here it is

That put is at late July 1983 which is a darn early 600XL.  And it is NTSC correct?

[+DrVenkman]

50 minutes ago, JGRAHAM2 said:

Other things to note

- the keyboard uses the 800XL style ribbon and connector

- the bodge wires on the switch (perhaps to use the rocker vs slider?)

- no traces or through holes for a monitor jack where the channel select switch is (no easy UAV install on this one!)

- why the bodge wires going under the cartridge port? Other pictures I’ve seen of this model don’t include those.

- the 28 pin socket for the BASIC ROM. The ROM itself is 24pin… Reminds me of some 1200XLs.

My Chelco made 600XL (rev 8A board) also has the 800XL style ribbon connector even though it is probably the "final" revision of the Chelco board. The lack of traces and pads for a video DIN is a real bummer but as a somewhat unusual machine, I'd be tempted to keep it fully stock anyway if it was mine. The 28-pin socket is likely provision for the use of an EPROM for the first units until mask ROMs were ready. 

[bfollowell]

2 hours ago, kheller2 said:

That put is at late July 1983 which is a darn early 600XL.  And it is NTSC correct?

 

I'm sure you're right, I mentioned earlier that it wasn't an NTSC model, but what I took to be the monitor port was just the power port. No monitor port, but pads not in place under the channel selector switch, that bites, unless you're planning to keep it stock of course.

 

[JGRAHAM2]

2 hours ago, kheller2 said:

That put is at late July 1983 which is a darn early 600XL.  And it is NTSC correct?

That is correct, it is NTSC and works with my US TV.

[JGRAHAM2]

2 hours ago, kheller2 said:

I’m curious about the RAM wiring if it’s easier to go 64K.   Take the cart port off and see where they go. 
 

 

 

 

The cart port is melted in place, so would have to be damaged to be removed. I did upgrade it to 64K with the SRAM upgrade that installs under the CPU with one solder point that is easily reversed. I am debating a video upgrade. I will leave this as an easily reversed upgrade if someone in the future wants to go back to stock.

[+kheller2]

1 hour ago, JGRAHAM2 said:

The cart port is melted in place, so would have to be damaged to be removed. I did upgrade it to 64K with the SRAM upgrade that installs under the CPU with one solder point that is easily reversed. I am debating a video upgrade. I will leave this as an easily reversed upgrade if someone in the future wants to go back to stock.

grr.  There is no need for that, it has plastic clips to lock it in place.  Although this being a CHELCO, the thing probably had dozens of screws and nuts holding the shield together.  You can figure it out with a multimeter and probe it out if you really wanted to know.

[JGRAHAM2]

1 hour ago, kheller2 said:

 this being a CHELCO, the thing probably had dozens of screws and nuts holding the shield together.

Actually, it had 3 screws and some H shaped clips that you twist to hold the top to the bottom . You have to remove the board to disassemble it. I will probe it out to see what is connected under the port. 

[+mytek]

I just bought this Chelco Rev 3 from @Paul Westphal and discovered how unusual it is. The story goes that Paul picked this up from eBay a few years back and it was listed as PAL because it had a PAL Antic and GTIA plugged into it. However as anyone who's read this topic knows it not only isn't a PAL board, but can't be easily made into one since it has no place on the circuit board for the PAL Color Burst oscillator. So the best you could do would be B&W PAL. Anyway Paul swapped out the PAL chips for NTSC and was using it as a chip tester.

 

After I got it, the first things I noticed was that it had a slide power switch instead of the normal rocker, and that the layout was completely different, with the BASIC ROM (in a 28 pin socket) and the OS ROM over to the left of the Cart Port, and not to the right as I was accustomed to seeing. So I started searching to find out what the deal was and came across this topic and a couple of others.

 

So without further ado here's the pics of my Chelco Rev 3 600XL...

 

Quirks: Slide Switch for Power, no pads for A/V DIN jack, 28 pin BASIC Socket, and a different layout,

dedicated to NTSC use ONLY. Also was missing +5V on PBI, which was added with a jumper.

 

Chelco used very high quality capacitors on this board, unlike a Rev 08 I have that has cheapo

disc ceramic caps instead.

 

 

 

The keyboard works, has a great feel, but could use a little retro-briting on the lettering & case,

and a fix to the scuffing on the console keys. I removed the model plate - it was pretty mangled.

 

 

 

Not the Hong Kong black label like on the OP's or one other I found pics of. Although it looks

like it might have had one at an earlier time - note the adhesive towards the edges.

 

 

 

 

This switch hole is smaller than normal to accommodate the power slide switch.

 

 

Chelco embossed in the inside plastic of the case.

 

 

 

I discovered two other owners of this same Chelco besides myself and the OP.

 

atari.area forum: ...new discovery

 

Although it isn't one of a kind, these do appear to be rare. I would love to know the history on this, especially why a slide switch was used for power, because even the 1200XL which predates this had a rocker.

 

- Michael

 

Edited March 28, 2022 by mytek

[Paul Westphal]

Nice thread!

Yeah I habe been using that particular 600xl for testing chips for quite some time.

 

I hit up Nir Dary and this is what he came up with for the 64k mod on this board ( pic ). I have done many NTSC 64k mods, but I didn't want to risk tanking the board if this mod didn't work. In fact I didn't want to sell it, but like everything else I sell on AA, it went to someone worthy that appreciates it for what it is

Edited March 28, 2022 by Paul Westphal

[Paul Westphal]

The Franken600XL came from a guy in California, via Ebay, about 6 years ago. $60 shipped.

Edited March 28, 2022 by Paul Westphal

[+mytek]

4 hours ago, Paul Westphal said:

The Franken600XL came from a guy in California, via Ebay, about 6 years ago. $60 shipped.

I appreciate that you didn't jack up the price much at all. eBay is absolutely getting ridiculous on A8's.

 

4 hours ago, Paul Westphal said:

In fact I didn't want to sell it, but like everything else I sell on AA, it went to someone worthy that appreciates it for what it is

I will take very good care of it, and it will get fully restored to it's former glory. Thanks for being willing to part with it.

 

[+mytek]

This label really doesn't make sense to me.

 

 

Because according to this...

Quote

The 600XL was made by Chelco Sound (Hong Kong) Limited from July to November 1983 (early NTSC units

with 7YJ serial numbers), by Atari-Wong Co. in Hong Kong from September 1983 to April 1984

(most NTSC/PAL units), and by Atari Taiwan Manufacturing Corp. in July 1984 (rare late PAL units).

LINK

 

This Chelco unit should have been made in Hong Kong not Taiwan as the label says. I really wonder if someone slapped a different label on it, because the case was made for the slide power switch which matches the board.

 

Edited March 29, 2022 by mytek

[_The Doctor__]

The label should have been black and went from edge to edge for most chelco hong kong units... there were variants though and this one isn't one of them.

So it looks to be a replaced label... the old glue is still there, if re labeled at the factory it wouldn't look like this either.

Edited March 29, 2022 by _The Doctor__