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ajacocks
January 14th, 2014, 08:55 AM
All,

As discussed on commodore128.org, I am making available a new run of Richard42's video DAC board, which, along with a GBS-8220 (or similar) CGA-VGA converter, will enable high-quality 80-column RGB output, from the Commodore 128, to a VGA monitor.

There is a good picture of the output from the original run of these boards, at Commodore128.org (http://www.commodore128.org/index.php?topic=3877.msg19829#msg19829).

My prices are as follows:

1. Bare PCB
Total (US): $10.00

2. Kit
Contains: bare PCB and components
Requires: soldering of component, GBS-8220 and power supply
Total (US): $40.00

3. Completed Board
Contains: populated PCB
What you need to do: Connect with your own CGA->VGA converter and power supply.
Total (US): $55.00

Thanks again to Richard42 for such a great design! I couldn't have done any of this without him. Sorry for the price increases over Richard, but a number of the parts have gone up in price, and so has shipping. I might be able to do better, if I get a number of orders.

This board will also work for IBM CGA, quite well.

Thanks!
- Alex

pearce_jj
January 14th, 2014, 11:18 AM
Nice! Are the Eagle files available for this?

Output looks almost too good... will be needing Blarrg processing (http://www.tested.com/tech/gaming/2982-a-link-to-the-past-how-to-add-crt-filters-to-16-bit-games-on-pc/) on it next :)

ajacocks
January 14th, 2014, 03:28 PM
All the board build files that Richard42 created are available from a post on commodore128.org. I'll upload mine, with the mods that I made, as soon as I know that they work.

Thanks!
- Alex

njroadfan
January 14th, 2014, 06:06 PM
Nice! Are the Eagle files available for this?

Output looks almost too good... will be needing Blarrg processing (http://www.tested.com/tech/gaming/2982-a-link-to-the-past-how-to-add-crt-filters-to-16-bit-games-on-pc/) on it next :)

Another option is the Micomsoft XRGB-Mini upscaler, which will add scanlines to the output video.

wesleyfurr
January 14th, 2014, 06:07 PM
This board will also work for IBM CGA, quite well.

Thanks!
- Alex

Just to make sure I'm understanding correctly...this converter will take the TTL CGA output from and IBM PC or compatible machine and convert it to a nicely usable VGA output? Does it support the CGA intensity pin? I've been dreaming of such a thing...I'll be anxiously awaiting a confirmation! :-)

Thanks,

Wesley

ajacocks
January 14th, 2014, 06:37 PM
Wesley,

This board converts TTL RGBI to analog CGA suitable for use with an arcade-type CGA-to-VGA adapter, like the Gonbes GBS-8220. In combination with that board, the output is actually very good. The adapter is indeed designed for intensity (hence RGBI), but it was originally designed for a Commodore 128. I'll be happy to test, in any way that anyone wants, but I don't have a perfectly running PC, at the moment.

I'll let everyone here know when I get the test boards back from the PCB vendor, and build them up, to make sure that all is well.

Thanks!
- Alex

SomeGuy
January 14th, 2014, 07:01 PM
I guess "CGA" has some slightly different meaning here in the context of arcade machines?

wesleyfurr
January 14th, 2014, 07:06 PM
Alex,

That is excellent...I'm definitely interested in one. Do you have any links you can share with screenshots, etc? I looked but wasn't finding much...though it is late and I'm getting tired, could just be me! Also, the only board I saw was using surface-mount components...but I'm not sure if that was yours or not...is yours a surface-mount design, or through-hole? I can solder through-hole, but I don't think I'm up to that much surface-mount yet...in which case I would need to opt for buying an assembled one.

Thanks!

Wesley

ajacocks
January 15th, 2014, 04:41 AM
Someguy: Yeah, to the arcade guys, "CGA" means 15Hz analog signalling.

Wesley: The board is entirely through-hole, and should be easy for a journeyman builder to assemble.

I'll work on taking some screenshots of my own, but this is from the original run:
http://www.commodore128.org/index.php?topic=3877.msg19829#msg19829

Here is the front of the board:
16869
And here is the back:
16868

Thanks!
- Alex

wesleyfurr
January 16th, 2014, 06:42 PM
That's awesome, and certainly something I feel comfy tackling. Definitely would like to buy one when they come available...maybe even two.

Thanks!!

Wesley

azog
January 17th, 2014, 02:55 AM
I have one of these back from when Richard originally offered them. It's a good deal. If you have a VGA monitor capable of doing CGA, you probably won't even need a VGA converter, just a 9-15 pin adapter.

ajacocks
January 17th, 2014, 05:13 AM
Yep. Though, I don't know how common those are, unless you have a multisync CRT. I have seen on eBay some new LCDs that are meant to be arcade display replacements that claim to take CGA/EGA as inputs, but those are definitely analog, and not digital.

They should work nicely with this DAC, though. I very much would like to do a new version of this DAC that supports EGA, but that's a future project.

- Alex

azog
January 17th, 2014, 05:32 AM
I have an older Coby LCD, I think it is a model TV-TF1514 I was able to connect it directly to my Atari MegaSTE and run both low res and medium res modes (they're both CGA modes; high res mode is VGA-ish enough that it also worked).

ajacocks
January 17th, 2014, 05:42 AM
Interesting. I wonder how many LCDs out there accept many more frequencies than expected?

- Alex

dabone
January 17th, 2014, 09:24 AM
I've got one of these with a amigamaniac rgb to svideo adapter, and it works very well for text, not so well for the demos.


Later,
dabone

ajacocks
January 17th, 2014, 09:32 AM
For Amigas, isn't it easier to use an Indivision? That's what I use on my A1200 and A4000.

- Alex

Maverick1978
January 17th, 2014, 07:02 PM
Indivisions are much more expensive, however.

ajacocks
January 18th, 2014, 07:34 AM
Glad to hear that some folks are still interested.

To update on status, the prototype boards have been sent to the fab, and I should have them back by January 29th. Once I build and verify those, I will make the production order, and will hopefully get those back within 2 weeks, so I should be able to start shipping boards and kits around the middle of February. I have already gotten the parts from DigiKey for my prototype.

Thanks!
- Alex

wesleyfurr
January 21st, 2014, 05:30 PM
Alex,

Thanks for the update and your work on these...I'll be looking forward to having one! If you ever work out an EGA version, you can count me in for one of those too!!

Thanks,

Wesley

ajacocks
January 24th, 2014, 04:42 PM
Just to give another update, I should have the prototype board in hand, on Monday. However, my company is sending me on travel, next week. So, I should have the completed prototype next weekend, and assuming that it works, I will start taking orders then.

Thanks!
- Alex

ajacocks
February 9th, 2014, 07:10 PM
All,

Sorry for the delay, I had a minor health problem that pushed me back a week.

So, I built the first prototype, and it turns out that there are 2 bad connections to the ground plane. I'll be talking to the PCB vendor to try to figure out what went wrong, tomorrow.

With the 2 fixups in place, though, the board works fine.

Thanks!
- Alex

ajacocks
February 14th, 2014, 04:50 PM
All,

I just ordered what will hopefully be the last round of prototypes. I moved some traces to prevent the ground plane disconnection that affected my first run.

Here are what will, hopefully, be the final boards.

Top:
17298

Bottom:
17299

I'll post another update when I successfully build this test board.

Thanks!
- Alex

wesleyfurr
February 14th, 2014, 04:54 PM
Alex,

Thanks for the updates and hard work...I'm really looking forward to the finished product!

Wesley

ajacocks
March 3rd, 2014, 06:47 PM
All,

I have completed the building of the test board, and it tests successfully!

I will post an update, tomorrow, with details on how I'm going to go about selling these.

Thanks for everyone's patience!
- Alex

dhoelzer
March 4th, 2014, 03:53 AM
Are you taking reservations for your initial run of boards?

wesleyfurr
March 4th, 2014, 04:24 AM
Wonderful news! I'll be over here standing in line... :-)

Thanks,

Wesley

ajacocks
March 5th, 2014, 04:18 PM
OK, thanks for everyone's patience! I started a blog, and posted some PayPal buttons on it.

http://he-insanity.blogspot.com/2014/03/commodore-128-cga-video-dac-board.html

Please let me know if I've forgotten anything, as this is a first, for me.

- Alex

wesleyfurr
March 5th, 2014, 05:13 PM
Alex,

Looks great. The only thing I see missing is a parts list. I've got some things to order for Mouser and Jameco, I could add these parts in...though it is probably just as easy and cheap to buy the whole kit from you!

Also, do you have any notes for how to connect the adapter to the GBS-8220? I see a header on it, but not sure what I would need to connect it...unless the 8220 has those type connections on the other end of the included cables? An ebay auction I found has photos of the cables, but they appear to be bare on the other end...

You note this works for PC CGA connections...does it just use a straight-through DB9 cable, or something special?

Thanks!!

Wesley

dhoelzer
March 5th, 2014, 05:25 PM
Thanks!! Order placed!

I'm so eager to see this thing work from the 80 column port! I haven't seen that in over 15 years!


OK, thanks for everyone's patience! I started a blog, and posted some PayPal buttons on it.

http://he-insanity.blogspot.com/2014/03/commodore-128-cga-video-dac-board.html

Please let me know if I've forgotten anything, as this is a first, for me.

- Alex

ajacocks
March 5th, 2014, 06:03 PM
Wesley,

Yeah, all of that info was on the original thread, on Commodore128.org, which seems to have gone missing, recently.

The parts list is as follows:


Qty Reference Part Number Description
======= =============== ====================== ================================
1 R13 309XBK-ND RES 309 OHM 1/4W 1% METAL FILM
1 R14 324XBK-ND RES 324 OHM 1/4W 1% METAL FILM
1 R15 365XBK-ND RES 365 OHM 1/4W 1% METAL FILM
2 R4,R5 4.64KXBK-ND RES 4.64K OHM 1/4W 1% METAL FILM
1 R6 4.32KXBK-ND RES 4.32K OHM 1/4W 1% METAL FILM
1 R19 13.0KXBK-ND RES 13.0K OHM 1/4W 1% METAL FILM
3 R10,R11,R12 10.0KXBK-ND RES 10.0K OHM 1/4W 1% METAL FILM
3 R7,R8,R9 15.0KXBK-ND RES 15.0K OHM 1/4W 1% METAL FILM
4 R3,R16,R17,R18 75QBK-ND RES 75 OHM 1/4W 5% CARBON FILM
1 R1 2.2KQBK-ND RES 2.2K OHM 1/4W 5% CARBON FILM
1 R2 3.3KQBK-ND RES 3.3K OHM 1/4W 5% CARBON FILM
4 C2,C3,C4,C5 478-3193-ND CAP CER 0.1UF 50V 20% RADIAL
1 C1 493-1144-ND CAP ALUM 10UF 100V 20% RADIAL
1 IC2 296-3577-5-ND IC TRIPLE 3-IN NOR GATE 14-DIP
1 IC1 TC74ACT244PF-ND IC BUFF/DVR TRI-ST DUAL 20DIP
1 IC3 296-4348-5-ND IC QUAD 2IN POS-NAND GATE 14-DIP
1 X1 621-009-260-042-ND CONN DSUB PLUG 9POS R/A GOLD
1 IC4 AD8044ANZ-ND IC OPAMP VF R-R QUAD LP 14DIP
1 POWER A1921-ND CONN HEADER VERT 2POS .100 TIN
1 H2 A1923-ND CONN HEADER VERT 6POS .100 TIN


There is a 6-pin pigtail that comes with the GBS-8220 board, that you can solder to the board, where you see that I attached headers. From left to right, those connections are:

Ground, horizontal sync, vertical sync, red, green, blue

The power connector (the 2-pin header) is, from left to right:

+5 VDC, ground

You will need to solder the supplied (with the GBS-8220) 2-pin pigtail to these 2 pins.

Those are DigiKey part numbers. Note that a number of the resistors are precision parts, and this is important for color fidelity.

As far as CGA goes, a regular straight-through CGA cable works fine.

For anyone else who orders, please note that I have parts on order, and shipping will happen as soon as I get parts in, and assemble boards.

Thanks!
- Alex

wesleyfurr
March 5th, 2014, 07:16 PM
There is a 6-pin pigtail that comes with the GBS-8220 board, that you can solder to the board, where you see that I attached headers. From left to right, those connections are:

Ground, horizontal sync, vertical sync, red, green, blue

The power connector (the 2-pin header) is, from left to right:

+5 VDC, ground

You will need to solder the supplied (with the GBS-8220) 2-pin pigtail to these 2 pins.

Left to right with which end up? :-)

So the 8220 provides 5v power to this converter via the 2-pin wire? I had assumed that wire provided power to the 8220...but I guess if it is tied to the power jack on the board, power would flow through both. Any thoughts on a power supply since the 8220 doesn't come with one? I was thinking maybe one from a USB hub. Do you know if the center pin on the power connector is positive?

Also...I noticed your web page says "or lo-res EGA"...can you clarify that statement? Would be even more awesome if this thing would do EGA conversion too...

Sorry to keep pestering you with all the questions... :-)

Just sent an order your way for the board...many many thanks again! I'm very excited...

Thanks,

Wesley

ajacocks
March 6th, 2014, 03:14 AM
Please note that I am (already) out of stock. I have ordered more PCBs and more parts kits. The parts should be in soon (< 5 days), but I suspect it will be ~ 2 weeks on the PCBs.

Please check this page for stock information, before ordering, unless you are willing to wait.

http://he-insanity.blogspot.com/2014/03/parts-inventory.html

Thanks!

SteveMarg
March 18th, 2014, 05:24 PM
I have several 8220 cables.
So for example, could I simply take two of the 2-wire cables and solder the bare ends together so I end up with a single wire with connectors on both ends?
That would make it much easier than going through the crimping.

ajacocks
March 18th, 2014, 08:33 PM
Steve,

The 8220 should have come with 2 different cables, both with connectors pre-attached to one end. One of the connectors has 2 wires, and is for power. The other has 6 wires, and is for sync and data. Each of them will need a connector, as specified on my assembly page, attached to the other end, which comes from the manufacturer bare.

Thanks!
- Alex

ajacocks
March 20th, 2014, 03:24 PM
All,

I now have stock of the boards and parts kits, and I have updated my inventory page, on the blog.

- Alex

lizardb0y
March 27th, 2014, 03:21 PM
All,

I now have stock of the boards and parts kits, and I have updated my inventory page, on the blog.



I've placed a kit order. Looking at the specs for the GBS-8200 and GBS-8220 the only difference I can see is the second VGA output. Does anyone have any reason to believe the 8200 wouldn't work with this?

SteveMarg
April 11th, 2014, 03:43 PM
Alex,
I just tried the board and it works fantastic. Thanks a lot.
Steve

ajacocks
April 12th, 2014, 07:00 AM
Steve,

I'm glad that it works well, for you.

- Alex

wesleyfurr
April 24th, 2014, 07:02 PM
I'll also have to chime in and say it works great! At least on an IBM Compatible with CGA graphics...I don't own a C128. I can't tell you how awesome it is to be running on a VGA monitor off the original video card on my old Tandy...

Thanks,

Wesley

SkydivinGirl
April 26th, 2014, 04:31 AM
Was I supposed to get the connectors for the wires from the GBS-8220 to plug into DAC board? I got the connectors that go on the board, but not the connectors that plug into it. :)

Heather

ajacocks
April 26th, 2014, 10:53 AM
Heather,

No, there weren't any parts shipped, for those.

The original design left the holes in the board unfilled, for the wires to be soldered in. However, in my experience, the wires would get frayed, from use. So, at the last minute, I decided to throw in the male connectors. I didn't include the female ones, though, since I figured that people might just use what they had laying around, since individual pin connections are fine, too.

If I do a version 2 of the board, I might include the female connectors, as well.

If you look at the bottom of this page http://he-insanity.blogspot.com/2014/03/video-dac-assembly-information.html, you will find the mating connectors, and the pins.

Thanks!
- Alex

SkydivinGirl
April 26th, 2014, 05:07 PM
Thanks for the explanation Alex! I'll get them ordered. :)

Heather

stamasd
April 27th, 2014, 08:27 PM
Awesome. Ordered a PCB because:
1. I have all of the parts except for the opamp which I ordered separately
2. will use my awesome soldering skillz :)
3. you're out of part kits anyway :p

I assume that the implied answer to lizardboy's question on the previous page "is there any reason to believe that this converter works only with the GBS-8220 but not the GBS-8200" is no. Correct? Because I have a GBS-8200.

BTW, I plan on using this with a Sinclair Spectrum 128k, which has TTL-level RGB outputs. Not exactly CGA, but close.

ajacocks
April 28th, 2014, 06:40 PM
stamasd,

Sorry, I didn't update my inventory. I do indeed have parts kits.

I don't have any reason to suspect that the 8200 wouldn't work, but I don't have one, so I couldn't test it. I'll also be happy to hear how this works with a Speccy.

Good luck!
- Alex

bouncedhex
April 28th, 2014, 09:56 PM
I recently received a GBS-8200 and I am using it with a C128 Video DAC board and a Tandy 1000 HX. I haven't spent much time with it yet, but so far it's working great.

wesleyfurr
May 4th, 2014, 05:27 PM
Do you have more of the PCB's on hand? I'm interested in building up a second one...

Thanks,

Wesley

ajacocks
May 4th, 2014, 05:33 PM
Yep, I have 4 more on hand, at the moment.

- Alex

SteveMarg
May 5th, 2014, 06:40 AM
I ended up encasing the DAC and the GBS boards inside a box, and using it as a monitor stand. :p

18612
18613
18619

ajacocks
May 5th, 2014, 07:04 AM
SteveMarg,

That is very nice! Are you a woodworker?

- Alex

SkydivinGirl
May 18th, 2014, 05:45 PM
I finally received and installed the connectors to connect the wires from the GBS 8200 to the Video DAC board. Here's pictures of the results.

First, the text color test. The colors are better than this picture.
http://s7.postimg.org/xq61kde9j/C128_Video_DAC_1.jpg (http://postimg.org/image/xq61kde9j/)

Second, two pictures from the Risen 80 column demo (http://csdb.dk/release/?id=44983). They are a little stretched from my widescreen monitor, but the colors are amazingly nice. There's also no lag in the video processing.
http://s7.postimg.org/mcji963qv/C128_Video_DAC_2.jpg (http://postimg.org/image/mcji963qv/) http://s7.postimg.org/u3vmtziif/C128_Video_DAC_3.jpg (http://postimg.org/image/u3vmtziif/)

Thanks for a great device Alex! My next test is on my Commodore PC 10-III. :)

Heather

ajacocks
May 18th, 2014, 05:51 PM
Thanks for the great screenshots, Heather!

SkydivinGirl
May 26th, 2014, 01:17 PM
Hi Alex! I would like to order one more bare PCB if you have one available. Thanks in advance!

Heather

tanuki
June 13th, 2014, 04:25 PM
Hi Alex,

I would like to buy a pre-assembled unit. Do you have any left?

Cheers!

ajacocks
June 13th, 2014, 06:47 PM
Tanuki,

I have an order in for more PCBs, but I have plenty of stock of the components. I should have stock in 2 weeks or so.

Thanks!
- Alex

tanuki
June 17th, 2014, 10:22 PM
Sounds good. I've subscribed to the thread & will watch for updates.

ajacocks
June 20th, 2014, 12:51 PM
I now have 4 PCBs in stock, should anyone want to place and order.

Going forward, I will probably only order PCBs when folks place orders, because the volume has dropped to a slow trickle.

Thanks!
- Alex

ajacocks
July 16th, 2014, 04:02 PM
All,

It seems like the sales of this board have slowed down. Going forward, I will only be buying the parts, and additional PCBs, when folks place orders. This means that while the board will still be available for sale, my pace at shipping, after I receive an order, may be slower, especially if I have to order PCBs.


Thanks!
- Alex

sprite9
August 23rd, 2014, 07:09 AM
I built my board this week and got it working with the GBS-8220 V3.0 today. Initially the GBS reported "No Signal" and pressing the Auto button didn't work. I had to go in to the Display Menu and set the resolution to 640x480 and then it worked.

Thanks Alex for providing this board!

CanadaPhil
October 4th, 2014, 12:41 PM
Hi All,

I know this is an old topic, but is there any chance of more of these becoming available?

I'm in the process of putting together all of my old vintage Commodore stuff, but its been in boxes for more than 10 years and I have had it all for 30 odd years now... Its in great condition though!

I really always had a soft spot for my 128, and kept it all... but I had left my 1902a monitor with my Sister as she needed a CGA capable display for an old PC she had. Sadly, that gave up the ghost many years ago.

I may be interested in getting 1 (maybe even 2) built units in the near future.

Very informative topic for me btw!
Thanks

ajacocks
October 4th, 2014, 05:04 PM
Phil,

I actually just ordered 3 more boards, of which I have sold 1, already. I should have the boards in hand, in a couple of weeks, so feel free to place an order, if you would like 1, or more, boards.

Thanks
- Alex

CanadaPhil
October 4th, 2014, 05:27 PM
Phil,

I actually just ordered 3 more boards, of which I have sold 1, already. I should have the boards in hand, in a couple of weeks, so feel free to place an order, if you would like 1, or more, boards.

Thanks
- Alex

Hi Alex,

Thanks for the reply!

I will let you know in a week or two maybe? I have a 1901 monochrome coming next week frim an Ebay buy. I will give that a try first to make sure all is well with my 128 before I start going crazy with it. Its all boxed with a 1351 mouse, 1750. REU, etc.. etc. Oh, looks like I don't have a functioning Floppy Drive. I had been looking to firing up GEOS128 :(

PS... I nearly fell off my chair when I saw a 1901 green monochrome monitor from an almost local seller on
ebay Canada! I actually had one of those nearly 30 years ago with my FIRST PC system... Which happened to be a Commodore PC-10. Looks like I am about to own one again!
:)

ajacocks
October 4th, 2014, 05:31 PM
OK, no problem.

CommodoreKid
October 4th, 2014, 10:46 PM
Seems that commodore128.org's domain expired, so I can't go there for more information. I am intrigued by this adapter and I am tempted to order one. However, I would like to know more before I give a solid yes/no. Any place I can look in the mean time?

ajacocks
October 5th, 2014, 07:10 AM
There is a fair amount of information in this thread. Is there something beyond that (and on the links from this thread to my blog page) that I can answer?

Thanks!
- Alex

CanadaPhil
October 6th, 2014, 08:44 AM
OK, no problem.

Hi again Alex

Just wanted to let you know I will pass for now. I have reacquired a 1902 and will make do with that for the time being.

However, I know that these old crt's that are still working are definitely on their last legs and I will need a new solution going forward.

Im still amazed no one has ever offered a readily available box for easily adapting vintage gear like 128's, early Amigas and vintage PC's running CGA via RGBi.

ajacocks
October 7th, 2014, 03:51 PM
OK, no problem.

- Alex

CommodoreKid
October 8th, 2014, 07:38 AM
I looked through the blog and reviewed the thread again, Alex. And I think I got most of the information that I was looking for.

The only thing that I didn't see that I was curious about were pictures of the finished functioning units plugged in. Know anywhere that I could see that?

ajacocks
October 8th, 2014, 01:44 PM
Follow the link to my blog, http://he-insanity.blogspot.com/, and there are pictures of completed boards.

Thanks!
- Alex

CommodoreKid
October 10th, 2014, 10:04 AM
Sorry for the delay. I think I'm going to hold off for now on buying a board for now.

Rick Ethridge
December 12th, 2014, 10:35 PM
commodore128.org is DOA.

ajacocks
December 13th, 2014, 04:23 AM
It has been down for quite a while, now. There is a fairly good copy of the site in archive.org's cache. Also, there is a standby site, at http://c-128.freeforums.net/.

If there information on the site that you were looking for?

Thanks!
- Alex

Charles Faust
December 15th, 2014, 06:08 AM
Are the completed DACs still available? I see a shopping cart on the blog, and I am very interested in obtaining at least one, maybe another one down the line I have a 128D and a 128 wedge.

ajacocks
July 6th, 2015, 11:30 AM
Charles,

Sorry for the slow response, I hadn't noticed the post.

Yes, the boards are still available. I am having time crunch issues, so I would much prefer that interested folks order the kit, rather than the completed board. That saves me several hours in assembly and testing. In fact, I am likely to be discontinuing the availability of the completed board, once my daughter is born, next month.

Thanks!
- Alex

Timigo
November 12th, 2015, 09:20 AM
Hello, Interested in this device. How can I buy it? Have no permission for PM.

ajacocks
November 12th, 2015, 01:11 PM
Timigo,

Sorry, but I'm not selling these, at the moment. I think that there is an alternate version being sold by Robert Bernardo, of the Fresno Commodore User's Group. You might want to contact him.

Thanks!
- Alex

RobertB
November 12th, 2015, 06:50 PM
I think that there is an alternate version being sold by Robert Bernardo, of the Fresno Commodore User's Group. You might want to contact him.
Heh, I'm not the seller of the C128 VGA adapter. It is John Carlsen of Palm Desert, California. Go to

http://www.bit-c128.com/

Truly,
Robert Bernardo
Fresno Commodore User Group
http://www.dickestel.com/fcug.htm