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Seattle, WA, USA

Posted Thu Jul 16, 2020 10:33 pm

A friend of mine and member of the AmigaLove Guild, "Walldog" Mike, sent me a scan of a multi-paged document he newly discovered that was taken by the owner of a Rejuvenator board based in England. That man apparently has a very early and somewhat rare model PAL A1000 - the kind that had an actual daughterboard like all NTSC models do. As a result, he was able to purchase and use a Rejuvenator board back in the day - something most European PAL A1000 owners could never do with their machines.

In any case, his Rejuvenator came with the typical thick, detailed installation manual written by Greg Tibbs and made by Expert Services, but it also came with another 5-page stapled document that I’ve not seen before and wanted to share with the community. I think the history nerds (of which I also consider myself) will find it a small yet interesting entry into the Commodore lexicon of early Amiga lore in relation to the Rejuvenator - one of the single greatest A1000 inventions ever brought to market.

The extra document was originally assembled and printed by a company that was a second distributor of the Rejuvenator.

This fact alone is worth noting, as originally I was under the impression that only Expert Services in Kentucky - who owned the copyrights and provided the capital to bring the boards to market - was the sole distributor. Apparently not, as The Grapevine Group out of Suffern, New York, also somehow worked a deal to distribute them as well.
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This is a piece of the Rejuvenator history in which I wish Greg Tibbs was still with us so I could ask him more about it. I will see if Scott Bennett of Expert Services recalls how that all went about...

Here is a PDF Download of the scanned extra document.

I have transcribed the first two pages that are unique to The Grapevine Group document below.

[Pg. 1]


Enclosed please find information pertaining to the advantages and features of the exciting new Amiga 1000 Rejuvenator.

Just to let you know a little more about us, The Grapevine Group is the largest distributor of Commodore chips and accessories in the United States. We have been in business since 1980. We guarantee our products and welcome your business.

[Pg. 2]

Amiga 1000 Rejuvenator Expansion Board
Bring out the best of your A-1000
Designed by Greg Tibbs

Distributed by the Grapevine Group

Now, as never before, you can truly tap the ultimate power of your A1000. With the addition of this unique board to your A-1000 hardware arsenal, you now have the ability to utilize the following enhancements; take advantage of the NEW 1-megabyte Agnus (graphic) chip, use Kickstart ROM in your machine with the ability to switch back and forth between using the internal Kickstart ROM or booting from Kickstart disk, 1 megabyte of internal on-board memory, a time of day clock, and a video slot that is currently configured for use with the FlickerFixer (user configurable for other video cards). Installation is easy, simply remove your original WCS (daughterboard) and plug in the Rejuvenator board onto existing pins, run 2 lines to the clock timing chip, and you are finished. Nothing this good has ever been this simple!

A few of the features of the Rejuvenator board are listed below, these should answer most questions, but if you have any particular questions, please do not hesitate to call us at the number listed at the end of this document.

  1. Allows use of the New 1 Meg Agnus and ECS Denise (CBM part # 8373) by replacing WCS with a new PCB. Old WCS daughterboard can eb sold to dealer or User Groups as they are not available in US as a repair part. Estimated value in good working condition: $50.
  2. Contains 1 Meg of chip ram on the Rejuvenator which becomes your new chip RAM. Uses 256Kx4 (1 Megabit technology) Drams.
  3. Motherboard chip ram becomes fast ram; a 512K Amiga will have 1.5 Mbytes of RAM after the conversion (1 Meg chip, 512K fast).
  4. Provision for A500/A2000 style ROM and/or converting 256K of motherboard ram into write protected WCS. Will support the 512K Rom when/if CBM ever uses it.
  5. Support for 1 Meg motherboard RAM conversion (piggybacked RAM chips) with slight modification.
  6. OKI battery-backed time-of-day clock chip at correct address
  7. A2000 style video slot subset - no parallel or audio support to slot (Normal audio & parallel ports work just fine).
  8. No modifications to the motherboard (NO soldering or trace cutting).
  9. A maximum of three clip lead wires are needed to go from the Rejuvenator to the motherboard (others are optional for video slot).
  10. Jumpers control motherboard RAM addressing to remove electronic conflicts with other RAM expansions. If not at $C00000 then memory must be ‘addmemed’ in.


After this, The Grapevine Group also printed and attached an article from Amazing Computing (AC) magazine. Published out of Massachusetts, AC was one of the greatest Amiga magazines ever made, It was written for adults and professionals and hard-core Amiga fans where games were a bonus, not a focus, The article in question is published in the edition from October, 1989.

I happen to have a near-complete collection of Amazing Computing and was astonished to learn - thanks to Walldog and his discovery - it had an interview with Greg himself after all this time! Incredibly, the interview was reprinted from an August 9th “formal conference” on CompuServe’s AmigaForums, and then published in the magazine in Oct 1989, then re-printed in the document sent by The Grapevine Group to the buyer of the Rejuvenator in the UK. Talk about a mouthful. Hah!

To help keep this history alive, I have also transcribed the entire interview of Greg in Amazing Computing by hand below. Not everyone is a fan of reading electronic PDFs. So here is the entire article in a device-agnostic format. I hope you enjoy it - I know I did!

From Amazing Computing, October, 1989

Greg Tibbs
A1000 Rejuvenator

edited by Richard Rae

On August 9th, 1989, CompuServe's AmigaForums hosted a formal conference with Gregory Tibbs, an electrical engineer at Wright-Patterson Air Force Base and president of Amiga-Dayton, an Ohio Amiga users group. Shortly after receiving a 1 meg Agnus chip for his A2000, Greg began investigating the possibilities of installing it in an Amiga 1000. The concept grew in features and capabilities until it became the "A1000 Rejuvenator", a WCS daughterboard replacement which brings many of the features of the A500 and A2000 to the original Amiga model. The following is a heavily edited transcript of that conference. Names in parentheses represent conference participants.

AC: Greg, I don't think I even have to introduce you or your new toy, so I will just start things off by asking you if you REALLY did this just because you were told you couldn't!

GT: I am a person motivated by challenges. When things get old hat, I get bored. So I really DID do the Rejuvenator because it was said that it couldn't be easily done! It took tons of work; I started in mid-May with the design concept, and I now have three working prototypes and am working toward getting the design mass produced.

(Jim W.) Greg, to crush the rumors, just exactly what do we get for our (how much?) money?

GT: The Rejuvenator acts, in its minimal configuration, as a 1 megabyte RAM upgrade; this RAM is your new Chip RAM. Your [existing] motherboard RAM, through clever design, becomes Fast RAM if you use the Kickstart ROM, or 256K of Fast RAM and 256K [of] WCS. In any case, a 512K Amiga winds up with 1.5 meg (with ROM) or 1.25 meg (with Kickstart WCS). For good measure, you also get an A2000 compatible real time clock and an A2000-style video slot subset.

AC: Greg, any cost estimate at this point?

GT: It's really too early to tell. A lot depends on negotiations with CBM to get the 1 meg Agnus and ROM at less than dealer repair list price. I am shooting for $500, but I am not guaranteeing that I will make it.

(Jim W.) Will you still be able to get the 512K Fast RAM if you use a MultiStart like the one from Michigan Software?

GT: The Rejuvenator acts just like the ROM-based add-ons. If there is no physical incompatibility then I guess you could keep it, but you are going to have [an empty] ROM socket on the Rejuvenator. One note. [The Rejuvenator] replaces the Kickstart daughterboard. CBM currently does not sell the WCS as a single repair parts item. You should be able to sell it to your dealer — assuming it is in good condition — or you could try to sell it to someone in a local user group. I feel it will be worth $50 to $60, as a good WCS Is hard to get nowadays.

AC: Greg, you said "but you'd have a ROM socket...". Will the Rejuvenator let one buy a KS ROM, plug it into the new daughterboard, and get the basic functionality of, say, a KwikStart board (plus the additional RAM)?

GT: Yes. Since the WCS goes away, you do not recover that memory as it is no longer in the computer. You will have the KS ROM plus 1.5 megabytes of RAM (on a 512K machine).

(Jon Scarpelli) How will this affect those of us with Insiders or Spirit boards?
Any incompatibilities? And what did you mean by video slot SUBset?

GT: I know that the Spirit board will physically fit. Other people who have seen the Insider say that it occupies less space than the Spirit board; if that is true, then it too should fit. I refer to the A1000 Rejuvenator's video slot being a subset because there are some lines [missing which] have little to do with video; if I provided a method of obtaining them from the motherboard, [it would turn] the design [into] a kludge. [The] beauty is that [the current design] requires no jumpers or trace cuts on the motherboard, and only three 'clip lead' jumpers from the Rejuvenator to the motherboard In particular, the A2000 video slot has complete access to the parallel port. It also has provisions for dual audio in/out. I decided to not run these wires, as I felt that most A1000 owners would use it for the flickerFixer (which has been tested) and the A23OO genlock (which hasn't). It was an engineering trade-off.

AC: I think my system may be typical of many; I have two devices on the expansion bus. What with all the problems we've heard related to loading, how would the Rejuvenator fit into such a system? Since it replaces the daughterboard, is it safe to say "if it works now, it will work with the Rejuvenator", or not?

GT: I have three points to make on this subject:

1) I could have used a Gary chip and turned the A1000 into a real A500. I didn't because I wanted to use PALs to emulate the A1000 timings as closely as possible. Pals also meant one less chip to negotiate for.

2) Because the timings are as close as I can make them, most expansion devices should work. I am using better (i.e. faster 15 nsec) PALs and have more than enough copper on the power busses to ensure that there will be no noise problem. On my prototypes I see little noise over what is on the motherboard's power bus.

3) The one problem that could occur is bus loading of the 68000. There is somewhat more capacitance on the address and data bus, and a couple more tri-state devices to leak and load the bus, This might make a marginal situation terrible, but I usually recommend going to the 68010 CPU, as it has CMOS drivers that are more noise immune.

AC: What WONT run with your video slot subset? Also, knowing how tight the 1000 is for space (especially with an Insider or Spirit installed), I have to ask: where does the video board GO???

GT: As I stated before, anything that uses the video slot's parallel port or audio mixing capability will not work. I haven't a list of what is available for the A2000 video slot, so I can't say what won't work.

The space situation is indeed tight. I intend to sell a new RF shield with the Rejuvenator that will add about .4" of clearance. You can also (optionally - you do not have to do this) trim the gold posts that the WCS mounts on by about .3". The only limit on how low you can go is a large electrolytic capacitor on the motherboard. The video card mounts horizontally, parallel to the Rejuvenator, between the power supply and the center case support.

AC: So, for example, a flickerFixer and an Insider could coexist?

The Rejuvenator turns
your A1000 into a 1.5
megabyte machine
that uses the 1 meg
Agnus. You will have
the option to add the
new ECS Denise when
it is available in the

GT: Sure. The only thing I know for sure that conflicts is LUCAS' Frances RAM board. It will fit, with some height adjustment in LUCAS/Frances, but Frances will occupy the same space as the video slot card.

(Jon Scarpelli) Do you get the sense that CBM is reluctant because of prolonging what they may view as an inevitable conversion to the A2xOO, or do they seem willing to listen/assist?

GT: I knew some form of this question was going to be asked. I don't think CBM knows WHAT to think about it. Anything more I can't say, as I don't want to jeopardize future negotiations with them.

(Willie Schreurs) Will there be support for the full ECS (Expanded (Enhanced?) Chip Set)? In other words, will Obese Agnus be joined by its similarly fattened brother and sister? Also, you earlier mentioned that the WCS goes. Does this mean no more ability to swap between Kickstarts on disk? <sob>

GT: If you have an ECS Denise beta you want to send me, I'll guarantee compatibility!

(Willie Schreurs) <Empty hands>

GT: Seriously, I will try to support the ECS Denise. It is supposed to be pin-for-pin compatible with the existing Denise. If so, then it should work. As far as the Kickstart disk, have faith! I mentioned that one of the jumper options is to turn 256K of your motherboard RAM into a new Kickstart RAM. My next PCB artwork will incorporate the ability to switch back and forth via a mechanical switch between Kickstart RAM and ROM. The change will take place after the next keyboard reset of the Amiga.

(Pat Fallon) Glad to hear of a product with video option for the 1000! Can you hazard a guess when it might be available?

GT: I certainly want to hit the Christmas market. I am aiming for mid-November. (Dean) How is the board installed? Are there connectors like on the WCS board or is it a slip over the posts and (maybe) solder?

GT: The board is larger than the original WCS. It extends over the three custom chip sockets, and the board has machined-pin adapters that fit in these 'sockets. The Paula and Denise chips plug into the Rejuvenator, along with the 1 meg Agnus. I had to have access to the entire data and address bus, so I needed all of the pins that were used by the WCS. I originally thought to solder those as I was concerned about noise. However, for this to be a commercial product, I can't have Joe Average Solderer mangling his A1000 beyond repair, so I use the same red slip-fit connectors as on the original WCS.

(Dean) Ok, so its just plug and go!

GT: Yes, along with the three clip leads to the motherboard.

(Daniel Habecker) My question has been half answered already. What about electrical compatibility with LUCAS/ Frances?

GT: I have a LUCAS board, but haven't tried it. Brad Fowles sent me a Frances board to check on the physical compatibility. Lucas is a little temperamental. It should work, but you might have to go through the problem of changing oscillators and/or 7474s again until you get it to work. The fact that I am using 15 nsec PALs will just about assure that you will have to 'recalibrate' it.

(Daniel Habecker) Thanks, I hope I can get it to work. It will give the 2500 a run for the money.

(Kbalid) Going back to the video slot. Is it possible to have more than one video slot on your product (or for that matter the 2000)? Why/why not?

GT: I am looking at changing how the right angle connection is made. I may go to a header block pin/socket arrangement to a 2nd PCB to obtain the right angle. If I do that, aside from vertical space considerations inside the A1000, it could be possible. However, it depends on what video cards you wish to connect. Some of the signals are meant to go from the video card to the A1000/A2000 if you are using a genlock. This would lead to a contention problem that could damage the video cards. If die purpose was a genlock and a flickerFixer, then okay, they might coexist. I buffer the digital RGB signals, so loading them will not be a problem.

(J. Mikell) Greg, three quick questions: 1) Availability of unpopulated boards? 2) Cost thereof? 3) Speculations on Toaster compatibility?

GT: To work with the Toaster?!! Sure! Just ask for the $1500 A2000 add-on option! The Toaster is supposed to occupy several slots of the A2000 as well as the video slot. There will be no way of making it work.

Bare PCBs will not be available for several reasons that 1 am not allowed to talk about here.

AC: Who will be handling production and distribution?

GT: I am not affiliated with any company. I have a friend who is an Amiga dealer and has lots of money, and we are nearing an agreement. Don't worry. You'll Find us.

AC: So you're not going through a distributor, you're doing it yourselves?

GT: It depends on the final production cost, which is now being estimated by an outside firm. I'm sure that it will be direct sales at first because we probably will be conservative on production quantities. When we get more confident and build thousands at a time, we will be able to lower the overall cost to afford a distribution layer.

(Charlie) I came in late, so I'm not sure I have a clear grasp of the thing itself; so could you briefly run down the major features/advantages? And mostly, has any provision been made for processor/co-processor options?

GT: [The Rejuvenator] turns your A1000 into a 1.5 megabyte machine that uses the 1 meg Agnus. You will have the option to add the new ECS Denise when it is available in the future. So, as long as CBM supports the A500 & A2000, this board which replaces your Kickstart RAM board will keep your A1000 current. It has an A2000-style video slot and a battery-backed real time clock. You can use the CBM KS ROM or, via a jumper, turn 512K of RAM into a new WCS (KS RAM). It will coexist with most major internal RAM expansions. And finally, the ROM socket is wired to accept the 512K byte ROM, should CBM ever decide to use one.

This is not a bus expansion product; it will not act like a coprocessor slot, and there is no provision for a math coprocessor.

(Caleb(BU) You mentioned a jumper for selection of KS ROM or RAM. Is this jumper internal, external, or a soft-switch?

GT: I have referred to it both ways. In my prototype, it is one of those square two pin jumper blocks. In the future, I will run it to an available flip-flop which will be clocked by the reset line, and have the flip-flop input a switch which will run outside of the case. To change, you'd toggle the switch and reboot via Ctrl-Amiga-Amiga. At that point the new setting would take hold.

(Caleb(BU) I expect that this will be a well-received product. As such, how small an initial production run do you expect to make? Are you chinking of doing something like ASDG and polling users first to see who will buy so as not to be under-stocked for too long?

GT: That depends more on finances. We plan to build 100-200 for a first run, depending on production costs. I am
reasonably sure that they will go quickly. But we need to impress the bank!

(Caleb(BU) I think you will, Greg. The Rejuvenator sounds like a winner!


Copyright © 1989 AmigaForums.
All Rights Reserved.

Amazing Computing V4.10 ©1989

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Posted Sat Jul 18, 2020 3:33 pm

So glad a little piece of this history is out there. I enjoyed reading the interview with Greg and responses in his own words. Enjoy

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