Hans W. | Feb. 26, 2025

Very good price/performance ratio

For PAL-1 - A MOS 6502 powered Computer Kit

Very good kit. I chose this kit because I wanted to actively familiarize myself with the hardware and software basics of the 6502 and the KIM-1. The circuit board is very well made and the components supplied are of very good quality. It is not a 1:1 KIM-1 replica, but the essential hardware and software features of the KIM-1 are present. The microprocessor and I/O chip are reused and that gives it a special appeal. For me it was also important that the kit was not too expensive. Overall, the kit has a very good price/performance ratio.

Response from KJXZZ | April 1, 2025

Thank you for your input!!!!

Happy hacking 6502~

William | June 2, 2024

Great kit

For PAL-1 - A MOS 6502 powered Computer Kit

I already have a MicroKIM-1 from back in ~2010, but I couldn't resist another KIM replica. I also want to support those who are keeping things alive.

I purchased all the available options at the same time, but so far, I've only built the PAL-1. It's a very nicely put together kit. I built it over a two-day weekend, taking breaks along the way and checking my work during the build. First power on was a success, and I keyed in the sample counting program with no issues. I'll start building the accessories next but anticipate no problems.

I already have mounting ideas, so I don't need the recommended 3D printed case, but I wonder what kind of key-caps would fit?

Response from KJXZZ | June 3, 2024

Thank you for your review!

The keys in the kit are chosen for the purpose of not requiring keycaps, the stem shape of this type of key switch makes it difficult to add normal keycaps to them.

To make typing easier, I write letters on the top of the stem with a paint marker (Schneider Maxx 271) and seemed to work well.

Best,
Liu

Andres | May 26, 2024

Great kit!

For PAL-1 - A MOS 6502 powered Computer Kit

Great kit to build and learn about the 6502. The quality is excellent and the shipping was super fast.

Response from KJXZZ | May 26, 2024

Thank you for your review!
Happy hacking 6502~

Kaveen | Sept. 10, 2022

Randall | Aug. 17, 2022

What a wounderful computer to build

For PAL-1 - A MOS 6502 powered Computer Kit

I had admired the original KIM-1 as a key part of computing history. I had also wanted one foer quite a while but as they are rare and expensive, including its Corsham sucessors, When I came across the PAL-1 I was excited to get it.

The kits were not hard to built even with my amateur soldering skill and every part of the PAL-1 just worked first go.

The documentation is awesome and I was able to get the basics going with little trouble and now I am learning about the wonderful world of 6502 assembly and machine language.

I recommend getting all the accessories as they provide a great deal more functionality and engagement.

Very much worth the cost.

Well done on nicely put together experience.

Randall.

Response from KJXZZ | Aug. 19, 2022

Thank you for your typing!

Happy hacking 6502 ;)

Will | July 18, 2022

Fantastic addition to the PAL-1 system

For PAL-1 ROM Expansion Kit V1.2

This addon was straightforward to put together and worked perfectly once assembled. The pre-programmed ROM comes loaded with useful monitors and languages:

eWoz, PBug, MS BASIC, Apple I Integer BASIC, VTL-02c, and a Memory Test Utility.

Kinda requires the RAM expansion, so go grab that too!

Response from KJXZZ | July 18, 2022

Thank you for the review!

The ROM expansion brings PAL-1 a good usability.

Will | July 18, 2022

Great addon and easy to assemble

For PAL-1 32KB RAM Expansion Kit

Board came with all parts include. Online BOM makes placing parts a cinch. Worked perfectly once assembled. The extra RAM is useful for large programs and projects.

Response from KJXZZ | July 18, 2022

Thanks for your input!

Online interactive BOM is highly recommended when assembling kits.

Daniel | July 14, 2022

Will | June 12, 2022

Fantastic Kit and great Maker

For PAL-1 - A MOS 6502 powered Computer Kit

Bought my PAL-1, and when it arrived, I soldered it up and when I ran into issues, I got quick help. The Kit was flawless and once I straightened out my mistakes, worked beautifully. If you are looking for a great 6502 trainer that is reminiscent of the KIM-1, this is the ticket.

I got the PAL-1, the motherboard expansion, and the 2nd RIOT at the same time. The PAL-1 was the most labor intensive to put together, but the motherboard had its share of soldering - lots and lots of pins :). The 2nd RIOT took about 5 minutes. All of the kits had all of their parts and went together smoothly. They all pretty much "just worked".

Response from KJXZZ | June 13, 2022

So glad you liked the kit~ Thanks for your review!

Thomas | May 7, 2022

Everything is fine.

For PAL-1 ROM Expansion Kit V1.2

3 Weeks ago i ordered the Kit. Today it arrived. Soldered the kit and another socket on the motherboard an it worked immediately. Thank for your work.

Response from KJXZZ | May 8, 2022

Thank you for your review! The ROM expansion will give you a convenient way to the 6502 world.

Dominic | Jan. 29, 2022

I like it so much I made an unboxing and assembly video

For *LR* PAL-1 | A KIM-1 clone Computer Kit

So far I have assembled three of these, one I gifted to a fellow 6502 enthusiast one I used my own keys and keycaps and the other is a straight out of the box install.

shipping on the first one was a month, shipping the other two was less than 10 days because I opted for the "express" post for only a couple extra dollars.

Video here: https://youtu.be/Juf5nu1Eh88

Response from KJXZZ | Jan. 30, 2022

Thank you for your review! Your video is very useful as a video assembly reference.

Dominic | Dec. 1, 2021

It's a real KIM

For PAL-1 - A MOS 6502 powered Computer Kit

Assembled and tested a hello program in two hours. Very nice. I collect KIMs but prefer replicas for everyday use.

I made an assembly video and will post it to YouTube.

Great features include the sturdy PCB. large, positive click feeling keypad keys.
Large digits, rs232 serial port integrated into the board. Just right size. Easy assembly, not an emulated KIM.. this is real hardware and clearly designed with care.

Minor design quibbles.... The kbd/serial selector should be a SPST switch, not a jumper. I'd like to see an on/off switch (nice but not necessary) and the keys are labeled at the bottom and this confuses me while searching for the right key to press I keep getting the wrong row because my eyes expect the label to be above the key. I'll label the keys myself to solve that.


I hope you make and sell thousands of these.

Shipping was five weeks to USA.

Response from KJXZZ | Dec. 1, 2021

Thank you for your review!

May a version E of PAL-1 is needed to optimize the two jumpers (replaced with two switches). I will try a version E after current version D PCB sold out.

David | Nov. 17, 2021

Hendrik-Jan | Oct. 19, 2021

Fantastic KIM-1 reproduction, and more

For PAL-1 - A MOS 6502 powered Computer Kit

The PAL-1 has probably become my favorite retrocomputing kit. What sets this kit apart are a few things:
1) Outstanding quality kit. The PCB is top notch, very nice design, high quality. Soldering is not too difficult. The components are well packaged. And the designer has really great eye for detail.
2) This is, in every meaningful way, a 'real' KIM-1. I've tried many different programs from the late '70s written for the KIM-1 and EVERYTHING works the same.
3) Often not appreciated enough, but that former point means there is TONS of software to be explored for this little machine, unlike so many retro-designs that are interesting in themselves which don't have this legacy (think Ben Eater 6502, RC2014, or the many Z80-based retroboards).
4) Of all my retro-kits, this one has the highest level of authenticity. Take any one of the manuals, tutorials etc from that age and you can just learn the 6502 as if it were 1977 (with the benefit of having huge collections of software and other KIM-1 resources through 2021 internet).
5) The kit is cheap. Really, I couldn't believe it. Only 80USD, and it does include a real 6502 (not the still in-production 65c02 version which would likely break some old software). Some sacrifices were made, including ditching the second 6532 RIOT, but that will only be interesting for people wanting to do interfacing with other hardware anyway, and is still available as a separate kit. Furthermore, unlike KIM-1 reproductions, the PAL-1 uses cheaper, easy-to-find components, such as a single-chip SRAM and recent capacitors that may look less vintage but you can be sure of will not go off anytime soon.
6) Unlike the real KIM-1, the PAL-1 comes with a serial connection on-board. The serial connection would be the single-most useful expansion for an original KIM-1, and is the very first thing I got for my reproduction KIM-1 which I also own. Since all original manuals include interfacing over serial connection, the fact that this is a standard feature of the PAL-1, it is in fact very much more easy (and cheaper) to get going than an original KIM-1.
7) The expansion kits are absolutely fantastic, and, again, cheap. If you ever shopped for still-in-production expansion kits for the original KIM-1 design, you will know what I mean. There are all the functions you would expect - RAM, cassette player interface, and that second RIOT, all on a very practical backplane. But, there is now also the ROM expansion card, which not only comes with a ROM that has some very useful software, but the ZIF socketed design makes it very easy to just put in a ROM with software of your own choosing (or own design).
8) The PAL-1 puts the KIM-1 back to where it was designed to be: a computer for learning and tinkering. A original KIM-1 is so expensive and rare, I wouldn't even dare to use it, even if I owned one. Even my reproduction KIM-1, although fantastic, is pretty expensive, and, honestly only very useful with expansion boards. The PAL-1 therefore really is the best kit around to explore the KIM-1 and the 6502 legacy.
9) The seller is amazing - not only has he created a fantastic kit but is also easy to get hold of for feedback and very obviously passionate for his product. Thanks Liu!

Response from KJXZZ | Oct. 19, 2021

The LONGEST review I ever received.

I think this review is useful for those who are interested in purchasing a new 6502 kit, the PAL-1 will be a good choice!

Thank You Hendrik-Jan!

David | Oct. 16, 2021

Great kit with great detail BOM documention

For PAL-1 - A MOS 6502 powered Computer Kit

Great kit that was easy to build using the BOM that came with the kit. Just need some more parts for the PAL-1 that I didn't buy the first time. And I just need to brush up my programming skills from the past to have some fun with this kit

Response from KJXZZ | Oct. 16, 2021

Thank you!

Hope you can get back a lot of fun from the past with the little kit.

Jorge | Oct. 8, 2021

Must have for retrocomputing fans!

For PAL-1 - A MOS 6502 powered Computer Kit

If you liked the original KIM-I and are nostalgic and trying to experience those old days this is a must have kit.

Very easy and fun to assemble, and it worked without a glitch, both using the display/keyboard and serial interfaces.

Documentation is very clear and loved the inclusion of old KIM-I docs and books.

Five stars !!

Cheers
Jorge

Response from KJXZZ | Oct. 8, 2021

Thank you for your typing!

Nostalgia always tendency to take on a rosy glow.

Bert | Sept. 23, 2021

great experience

For PAL-1 - A MOS 6502 powered Computer Kit

Assembly was no problem and everything works on first run. Nice work!

One hint: If you want to play Asteroids from The first book of KIM-1 you need a second Timer (RIOT expansion) or change the program to use the first timer.

Response from KJXZZ | Sept. 24, 2021

Thank you for your review!

Have fun with the old assembly game!!!

Bill | July 30, 2021

PAL-1 - A MOS 6502 powered Computer Kit

For PAL-1 - A MOS 6502 powered Computer Kit

Great kit to build !!! Worked 1st go !!! Highly Recommended !!!

Silk screened PCB, quality parts, great documentation !!!

Best value for money !!!

Response from KJXZZ | July 30, 2021

Thank you for your review!

Have fun with the little 8-bit machine~

Christian | July 29, 2021

Best 6502 kit on the market!

For PAL-1 - A MOS 6502 powered Computer Kit

I've been building a lot of 6502 and Z80 computers lately, and PAL-1 is the best 6502 kit I've found. This is a clone of the MicroKIM which is itself a slightly miniaturized but still true to form KIM. The board runs the actual KIM ROMs, no emulator here.

Construction is simple, parts are well labelled and high quality. I bought RIOT/RAM/ROM/Motherboard/Tape kit and it all went together very quickly. I don't think I'm going to use the tape adaptor but it's nice to have.

Response from KJXZZ | July 29, 2021

Thank you for your review!

Real hardware with vintage software feels great!

John | June 12, 2021

Another essential for the PAL-1

For PAL-1 ROM Expansion Kit

This kit provides a way of quickly using some key software - such as BASIC - without the hassle of loading from tape or terminal. An EPROM populated with software is included, and if you have a cheap EPROM programmer you can make your own EPROMS. It’s great way to learn about state-of-the-art 8bit computers, circa 1979 ;-)

Response from KJXZZ | June 12, 2021

Thank you for the quick review of the latest expansion of the PAL-1 kit!

Hope to see your code running on it someday :)

Peter | May 20, 2021

Excellent kit

For PAL-1 - A MOS 6502 powered Computer Kit

Great kit. Good price. Took a while to get here. Well presented. Quality parts. Easy to build. Worked first time.

Response from KJXZZ | May 21, 2021

Thank you for your review!

Happy hacking 6502!

Philippe | April 5, 2021

Excellent! Tons of fun!

For PAL-1 Motherboard Expansion Kit

Very nice kit and expansions. Hours of fun guaranteed!

I created a 3D printed enclosure for the main PCB (working on the motherboard now). Please feel free to visit https://www.thingiverse.com/thing:4817583

Response from KJXZZ | April 6, 2021

WOW, this is amazing!

Jimmy | March 29, 2021

All the additional I/O you could ever need!

For PAL-1 2nd RIOT Expansion Kit

This wonderful add-on board gives you all the additional I/O you could ever need! With this add-on, your PAL-1 gets one step closer to operating exactly as the original KIM-1. Shipped out very quickly and very easy to assemble and get working.

Response from KJXZZ | April 2, 2021

Thank you for your review. This expansion can bring back the lost part of KIM-1.

Happy hacking 6502

Jimmy | March 29, 2021

This is a fantastic add on for your PAL-1 KIM Clone!

For PAL-1 Motherboard Expansion Kit

This is a fantastic addon for the PAL-1. If offers you more than enough interfaces to add third party expansion to your PAL-1 or even some you may build yourself.
It ships out very quickly and well secured, very easy to put together and get working right away.
Couldn't ask for me.

Response from KJXZZ | April 2, 2021

Thank you for your review.

Happy hacking 6502

Jimmy | March 29, 2021

All the RAM you could every want!

For PAL-1 32KB RAM Expansion Kit

This great add-on kit will give you all the RAM you could every want! There is no way you will ever manage to utilize ALL of this 32k addon for the PAL-1. You will never have an issue due to not enough memory again.
Ships out very quickly and is very easy to assemble. This is the perfect combination along with the RIOT and expansion board upgrades.

Response from KJXZZ | April 2, 2021

Thank you for your review. The 1152 bytes RAM is not enough today. If the 5K RAM is also not enough for you, the 32K addon is for you. It can provide more practical RAM space for daily play.

Happy hacking 6502

Neal | March 24, 2021

Very happy with the PAL-1 kit

For PAL-1 - A MOS 6502 powered Computer Kit

The PAL-1 kit was complete in all respects. The documentation was very good. Assembly straightforward. Moderate soldering skills more than suffice. Kit worked immediately on completion, no trouble-shooting required. A project this elegant deserved a gold frame, and that's how I mounted it.

Response from KJXZZ | April 2, 2021

Thank you for your review

Jacob | March 15, 2021

Feels great to celebrate computing history with this replica

For PAL-1 - A MOS 6502 powered Computer Kit

This KIM-1 clone has a very high quality PCB which had no tricky bits to solder. I saw the complaints about the transistor footprints, but having just finished an Elenco single-sided hand-traced PCB project, I thought it was easy enough. Every IC is socketed, which makes replacing and borrowing chips for other projects much easier. The jumper switches for I/O and memory selectors are conveniently placed. The RAM and RIOT expansion boards and backplane are nicely designed, as well, with lots of space for your projects.

I communicated with the seller via Tindie, and they were quite responsive. I learned that the DEN pin does not have a pull-up/pull-down resistor, as designed - instead, the PAL-1 32K RAM Board has a pull-up resistor on it.

The documentation is available on pal.aibs.ws - click "资料下载" to find the manuals, ROM binaries, and schematics.

This is a great 6502 single-board computer for electronics tinkerers, as every useful pin is pulled out to the pin header and the expansion board invites you to plug a half dozen cards in at once. BYO address decoder circuits!

Response from KJXZZ | March 17, 2021

Thank you for your review!

BYO cards and fill full the motherboard ;)

Guus | March 12, 2021

Board is fine and worked just from the start.

For PAL-1 - A MOS 6502 powered Computer Kit

Very nice implementation. Board worked right away.
Assembly was fast and all components do fit just fine.
I mounted a heartsink to the voltage regulator.
Will replace the CPU by a 65C02 later on, just because I can. :-)

Hints for improvement:
- Put a protection diode across the voltage regulator. This may be needed if the board gets power from the expansion connector.
- Make a footprint to accomodate both the small (Square) oscillator and the bigger one. This way, another frequency can be fitted easier.

Response from KJXZZ | March 17, 2021

Thank you for your review!

About the 65C02 upgrade, the SST switch will not function normally, you can check this picture on hans' site: http://retro.hansotten.nl/wp-content/uploads/2021/01/Single-Step_Fix.jpg to fix the SST problem while using 65C02.

Theo | March 12, 2021

High quality kit and great fun to build

For PAL-1 - A MOS 6502 powered Computer Kit

Good quality printed circuit boards, easy to solder with nice fitting of components and clear labeling.
Worked first time, so that was a fun experience without any frustration. I like the big buttons and the large LED displays.
I have pasted a strip of red Lee color filter over the displays because they were rather bright for my eyes, and they look great.
The new user manuals are fine and in the download I found lots of KIM-1 and 6502 documentation.
I included the optional motherboard with RAM and RIOT in my order, and they were also fun and easy to build.
Have not done much programming yet but so far so good and I would recommend this kit for any retro-computing fan that would like to have some 1970's KIM-1 experience.

Response from KJXZZ | March 17, 2021

Thank you for your review!

Wish this KIM-1 clone will bring you a happy experience.

Jim | March 9, 2021

Makes a great kit even better!

For PAL-1 Motherboard Expansion Kit

I have the expansion board, the 32K memory board, and the RIOT board all built and working. They went together quickly and work as they should. The additional memory lets me run BASIC and Forth as well as a the complete version of JMON (including the assembler). Plenty of extra slots for future projects also. This continues to be a fun project to tinker with.

Response from KJXZZ | March 10, 2021

Thank you for your review!

Your repository on github is very useful, look forward to more from you!

Thanks!

Patrick | March 6, 2021

Fantastic kit

For PAL-1 - A MOS 6502 powered Computer Kit

What a fantastic kit, I have always wanted a KIM-1 like board and this is a very nice replica. The PCB and components were good quality and packaged well, the instructions were easy to follow, though I have quite a bit of build experience, so not sure for the beginner. The kit worked first time and was using it without issue, I had to try a couple of cables to get serial working but that’s always an issue for me with anything RS232, happens with other kits I have and is always hit and miss.

Now looking forward to getting to learn the system, I also ordered ordered the expansion options and should be able have some fun building and using them in the near future.

Keep up the great work and thanks for making this, I will look forward to your future developments with this product range and anything new you do.

Response from KJXZZ | March 6, 2021

Thank you for your review!

The RS232 cable for PAL-1 need to be an extension cable, a Null-Modem cable cannot be used.

If you are using a real RS232 port, you need an extension cable to connect to PAL-1 (Tx-Tx, Rx-Rx).
If you use a USB to RS232 cable, you can try a crossover gender changer between RS232 cable and PAL-1. Most USB to RS232 cable exchange Tx and Rx internally, the crossover gender changer can exchange TX, RX again, so you will connect Tx to Tx and Rx to Rx as required.

Have fun with PAL-1!
Happy hacking 6502!

Philippe | Feb. 10, 2021

Excellent! A good source of old fashioned fun!

For PAL-1 - A MOS 6502 powered Computer Kit

Soldering everything took me about two hours.

Some soldering pads are really, really close together (all the transistors), and I managed to create a short. Even though I identified and fixed the problem relatively quickly, that seems to have damaged the 6532. I got a few hours of fun, but eventually the 6532 gave up the ghost (only the last two digits where showing and the board was pretty much unresponsive). I bought a new RIOT from a local vendor (thank God for those dusty shops that still have stock from the 80s) and the board is now running properly.

My biggest gripe is the the DB9 serial port. It is a pain. I understand striving for historical accuracy, but some things like RS-232 are better left in the past where nobody is missing them. I spent a small fortune on cables, RS-232 level shifters, gender changers, and null-modem adapters before I could find a solution that works with the PC that I use as a terminal. I suggest to include pads on the PCB to solder a USB to serial adapter permanently. That would give instant, no grief USB connectivity and power and would save a few components including the power regulation section and the DB9 connector. The only incentive to keep RS232 over a DB9/DB25 connector would be to connect vintage equipment, and the components for that could be sold to interested parties as a separate kit (and include a real level shifter to achieve real RS232 levels).

As far as documentation and design files, it's all very minimal and cannot really qualify as open source. There is definitely room for improvement.

Thank you M. Liu. I hope you take constructive criticism well ;-) Whenever you come up with v. 2.0, let me know!

Response from KJXZZ | Feb. 24, 2021

Thank you!

The 6532 chip, which hard to find nowadays, comes from recycle/refurbish supplier.

Even though I always check the working status before packaging each kit, there is still a certain probability get a flaw chip, such as long-term stability.
If I can shipping you another package in the future, I can send you another 6532 for backup.

The serial port is for historical accuracy, your suggestion may apply on a brand new 8-bit computer in the future.

Regarding documentation, you can find a lot of documentation at http://retro.hansotten.nl/6502-sbc/, hope you can find what you need.

Thank you again for your useful comments!

Jim | Jan. 24, 2021

Great little kit!

For PAL-1 - A MOS 6502 powered Computer Kit

My first computer was 6502 based (OSI C1P) and this has been fun to play with. The kit went together fairly easily, but there are no step-by-step instructions so it isn't for the beginner. But if you've done some building, this one is fairly easy to figure out. As has been mentioned, the pads for the transistors are a bit close together. When I first powered up, the right digit was dead. I looked a the schematic and then remembered I had a solder bridge with one of the transistors that I thought I'd cleaned out. Turns out I hadn't cleaned it good enough and a few minutes with the solder sucker and the soldering iron had things working as they should. Buttons have a nice feel to them. The voltage regulator runs a bit warm even at 6 volts (and really warm at 7 volts), so I'll probably add a heatsink (I have a collection of salvaged ones, so why not..). The design is similar to a previous clone, but I like the way the LEDs are down near the keypad. They are large and bright. Overall a great kit!!!

Response from KJXZZ | Feb. 24, 2021

Thank you!
I'll try to create some "video manual" for the system.

and, transistor pads are upgraded in REV. D.

Nils | Jan. 16, 2021

What a great choice

For PAL-1 - A MOS 6502 powered Computer Kit

I‘ve always wanted to have a KIM-1 or a replik, as the original is out of range.
And with this easy to assemble kit I‘ve got exactly this.
The boards layout is cleaned up, all parts are labeled and fit perfekt. It took me around 3 to 4 hours to complete the board.

The online manual is detailed and complete. A Tip: for more software look at hansotten.nl micro kim pages.
Shipping was very fast and took exactly 12 days to germany.

Response from KJXZZ | Feb. 24, 2021

YES, hansotten.nl is one of the top site of MOS6502 based system.

Thank you!