TEC-1 Inc.

83 orders since Dec 13, 2023

Baulkham Hills, NSW, Australia

Custom Work Available

View Store

Come and learn how computers work on a fundamental level, with the TEC-1G!

Overall Rating:

Review Breakdown

Average Ratings

Product: (4.80)

Documentation: (3.80)

Shipping: (4.60)

Communication: (5.00)

All Reviews

David | Oct. 21, 2024

Well done.

For TEC-1G Replacement Power Switch

A nice retrofit kit. Instructions are very clear and make installing relatively painless and can't complain about the price :-) Thanks.

Bob | April 2, 2024

A great Z80-based single board computer

For TEC-1G Z80 Single Board Computer Kit

So, back in the early 80's, while in graduate school, I got fascinated with Z80-based boards and with Z80 assembly language. Then life happened and my interest in all things Z80 had to be put on hold. Fast forward to 2023 and I am now newly retired and I am going back to a Z80-based computer life.

I was excited to find out about the TEC1G on Tindie in the late 2023. I had read about the original TEC and its clone, the Southern Cross, on the web, so when I saw the TEC1G listing I decided to give it a shot. This new board is the original TEC on steroids. Do you like lots of LED's AND 7-segment displays AND an LCD screen plus a vastly updated monitor, that is continuously updated? Add to those a space for extra ROM/RAM, and interfaces galore (keyboard, joystick, room for additional extras and access to the Z80 bus). A geek's paradise I say, as I type hex code on the well lit, by LED's, TEC1G keyboard. My wife rolls her eyes when she sees me typing in the dark, but I don't mind because my keyboard supplies all the light I need.

Australian Post was really good with updates about the shipment status. The package arrived safely in Cincinnati, OH-US within two weeks or so. Everything was nicely and securely packaged.

The designer, Mark, along with the software designer, Brian, have a boatload of information about the hardware and the software on Github and it is imperative that you consult all that info before you start assembling the board. I learned a lot by spending a few hours reading the material and looking at the schematics; lots of fun. I cannot speak highly enough of Mark's help. Every time I had a question he would answer my email in a timely fashion and with details that would help me understand the TEC1G better. It was a real pleasure dealing with Mark.

The board is now assembled and operational. The TEC1G is connected to a Windows 11 PC via the supplied FTDI module. I use NotePad++ as my editor and ZMAC as one of the assemblers; works like a charm with TeraTem. I was all excited about the first TEC1G I got and as a result I ordered a second one w/o the keyboard to play on a hardware level, interfacing it with RC2014-based boards.

Overall I am very happy with the product and the support I received.

Bob G.

Response from TEC-1 Inc. | April 9, 2024

What a fantastic review! Had me grinning from ear to ear reading it. Thanks so much... and the fun isn't over yet... Wait till you see what is around the corner. :)

Alec | March 26, 2024

Seems really cool if it will work

For TEC-1G Z80 Single Board Computer Kit

I got the kit and put it together which was really easy with the amazing layout of the parts. My only issue is I cant get it to work. I get power i get the LCD to light up but nothing else. I have probed all day and I cannot find any issues. I wish there was something that shows what the jumpers do as I have no idea if they are set correctly or not. I don't have a Facebook and really don't want to get one just for this project. I have checked rails all over all looks good. I used a logic probe and see activity on the CPU data lines so it is doing something. I have tried other roms as I have the 27c512 on hand to do so but even just the diag rom nothing happens. I am just not sure where to go for help at this point. But this still looks amazing and was fun to build. I lost a switch and the seller happily helped me source a replacement which worked

EDIT:
Found I did not have a diode correct and flipping it got it working I also had to set rom size to 28 not 24 like all the pictures the documentation for this is really bad it more documented for the software than the setting the hardware has which was frustrating

Response from TEC-1 Inc. | April 9, 2024

Hi Alec. Glad you got the TEC-1G eventually running. As with Bob (the other reviewer above) there are many ways to get in touch with me if you have any problems, including on Tindie. (As you did for the switch.) But yes, it would have been difficult to diagnose the reversed diode problem in any case. Glad you found it.

On the topic of documentation... That's a fair call. The documentation is not complete by any stretch of the imagination and that is because it was a rush to get the PCB made, then everyone wanted kits, and then everyone wants the add-on boards (RTC and SD Card) and then there are other boards to make (new one coming soon) and what always suffers is the documentation. It doesn't help that the majority of users of the TEC-1G are old hands at the TEC-1 from 40 years ago, so they are used to how they generally run and work on minimal documentation. But that is no excuse and I apologize for any frustration. BTW, the schematic has a few notes on it that could be helpful, too. I'm starting to make a video series on assembling the 1G and hopefully that will be of help, and yes, I will get onto the documentation as well. Promise. :)

Eric | March 22, 2024

Awesome Little Kit!

For TEC-1G Z80 Single Board Computer Kit

I remember seeing Talking Electronics magazines at the public library when I was younger, but it was out of my price range to order from Australia and have it shipped to Wisconsin USA. Fast forward 40 years and I finally have the time & money to tinker around. I did play around with Radio Shack TRS-80 computers growing up, but never dug into the Z-80 Assembly programming.

Shipping was pretty quick from AUS to Detroit, MI and I had no issues with customs or delivery. Everything was well packed and made the voyage without damage. I printed out all of the information on the Tindie & Github site while the package was in transit.

Upon Receipt of Unit # 129 (TEC-1G Z80 Computer - Full Kit of Parts w/ fullsik keys), I did a quick inventory and only needed to pull a few resistors, capacitors and sockets out of my stock. One of the resistor networks was cracked / split down the middle, so I did have to refresh my stock with a quick Amazon order.

Read the errata specific to the pcb that you have before starting and follow the instructions. I had to reverse the polarity on the probe header and install the bodge wire, nothing was complex or difficult. The PCB I had was green and all of the traces came pre cut with a Dremel Tool bit.

I did struggle with the little LEDs which backlight the keys – might have been my Hakko FX888D soldering station was a little too hot, so the legs on a few of the white LEDs melted off. Luckily I ordered the Graphical LCD Kit, Micro SD & GIO Kit, Matrix QWERTY & Real Time Clock Kits and Mark hooked me up with 3 spare white LED’s when that order shipped. My junk box did not have any white LED’s that had the same size and I could not find a similar LED on Amazon.

It was easier to insert the LED first and then the key switch, flip the board over to tack solder one leg in, then gently pull it flush to the board. Once I was happy that everything fit correctly, I went ahead and soldered both legs and the switch contacts.

The rest of the assembly & soldering went smoothly. I had extra sockets in my junk box, so I went ahead and socketed the 7 Segment LED’s, the 8 Segment Bar LED and a few other chips. I had a 10 Bar LED, but I think LED L2 & L5 + the 8 Bar LED equals the 10 Bar LED.

Take your time, confirm component values with a DMM or one of those component tester kits and you’ll be fine. I did have to desolder the 9 Key LED & switch, as that LED died. Luckily my Hakko FR301 desoldering tool (money well spent) saved me and I had the repair done in 2 minutes.

I used my adjustable DC power supply set at 5 volts for testing and final power. Jumper settings had to be tweaked, but I was greeted with “TEC-1G Main Menu”. Now for the bad news…

Digging thru my old junk box, I found an adjustable wall wart that had 6, 9 & 12 V Settings and a barrel jack that fit. I confirmed 9 volts and tip + with my multi meter (twice) and then attempted to power the board via the barrel jack and voltage regulator. Needless to say, the wall wart was junk and the voltage jumped to 12V and I yanked the plug.

My plan was to start playing with the TEC-1G, but now I get to trouble shoot whatever I ended up frying. I didn’t let any smoke out, so I’m hoping if I damaged any chips I’ll be able to pull them out of my RC 2014 modules. I’ll post this review on the Facebook Group and see what kind of feedback or suggestions I get.

Other than my self-inflicted damage, the kit was a fun build and I’m looking forward to getting it fired up again! Good Job Mark!

Gary | Jan. 29, 2024

Kit is robust! Active community

For TEC-1G Z80 Single Board Computer Kit

Updated 31 Jan 2024
Since writing the original review I have had a lot of interaction with the team who have made the kit possible. They have been super supportive, professional and have not been (too) offended by my original review. Whilst I still abhor Facebook, in this case it has not diminished the experience.

There are some excellent points brought up in the sellers response and I should have thought harder about what I wrote. The seller is correct about the time and effort put into this and am disappointed that my review diminished that effort. My apologies and mea culpa. I have updated the rating to reflect my experience and the sellers feedback.

I am enjoying the kit and would definitely recommend it for learning about the Z80. I hope to get involved in improving the documentation as this is a community project...and also for penance!

Original review below:
tldr;
If you are a beginner to Z80 and microprocessor trainers, or are a beginner building kits, this is not the kit for you.
Only buy this kit if you are comfortable being restricted to Facebook support only.

Pro's
- Is a fun kit to build for experienced kit builders
- High nostalgia value
- Seems to work well once up and running.
- Mon3 manual is quite good.

Con's
- The group has chosen Facebook as their primary communications channel. Guys/gals, please consider other options in addition to Facebook.
- Kit installation manual is incomplete.
- It is important to read the errata sheet before building the kit.
- Some of the changes in the errata had been made to the board but not all.
- The 2 switches for selecting the monitor don't fit properly without having to reshape the pins.
- The large oscillator switch can obstruct the key caps.
- The power switch is flaky. If I put the switch all of the way on, it switches off again.
- The 5 volt linear reg runs hot but is not out of spec. I would recommend using a modern regulator instead.
- My kit briefly had issues with missing characters on the LCD but has not been seen since. I am not the only person to observe this.
- The magazine examples at the Github page do not work with Mon3. After adjusting the org from 0900H to 4000H only some of the examples work due different monitor calls with Mon3. I did manage to get the examples working by making the appropriate changes to the monitor calls.
- The magazine examples are poorly commented. There are no references to which magazine the example comes from, and there is minimal if any explanation of what the code is doing. You will be lost if you are a beginner to Z80 trying to use the examples.
- Expansion board/TEC deck options are limited.

Response from TEC-1 Inc. | Jan. 30, 2024

First review and overall a negative one. Ouch! :(
Well let me address your concerns and comments, some of which I unashamedly agree with.

> Title: Needs More Polish...

Well sure... But polish takes either time or money, which would add to the cost or affect availability. I am not a corporation or even a small company. I am but a user of the original TEC-1 some 40 years ago that has updated it to be a little more capable. I could have left it at releasing just the PCB and be done with it. Instead, the kit is put together at the lowest cost to the user possible. I have thankfully had help along the way, again from pure volunteering of people's time to make the Monitor software and the diagnostics. The GitHub, used largely for documentation, is written 99% by me. All this while holding down a normal 9-5 job. The "polish" will improve in terms of the documentation, but I won't be spending money on fancy boxes with pretty foam cutouts which is what I have seen from some of the pre-made kits. I think this one is on a par with a few of the RC2014 kits or will get there soon.

> If you are a beginner to Z80 and microprocessor trainers, or are a beginner building kits, this is not the kit for you.

I'd like to know what Z80 kit out there IS aimed at the pure beginner? The RC2014? I don't think so. The Agon Lite? Hardly. The Z80 Retro? Getting close but I think with the minimal of complex parts in this kit, I don't think it gets much simpler in design than the TEC-1G. Right out of the gate you have a display on the board (2 types) that lend themselves to being standalone, rather than needing serial communications and being tethered to a PC. No, this is not an absolute beginners kit, with over 250 parts to solder in. But neither is it a complex Z80 build. Sometimes to learn, you have to push your limits.

> Listed Pros

Thank you... At least there is SOMETHING good about the kit! ;)

> The group has chosen Facebook as their primary communications channel. Guys/gals, please consider other options in addition to Facebook.

I'm pretty sure you are the most recent member in our group and you yourself listed the issues with all the other forums out there. And we started on Facebook many years ago and have the membership numbers there, meaning if anyone has a problem, I doubt it goes unanswered for long than about 5 minutes. But as I said to you, there is also a sub-Reddit for the TEC-1 (https://www.reddit.com/r/TEC1/) that I started 2 years ago and have had not a single person join it! (You yourself said Reddit has gone to pot.) Not sure if you can respond (or better, Edit) your review and this reply, but I would love your feedback on your Facebook experience, now that we have the non-spam rules relaxed and all your posts approved. Oh and feel free to suggest what other options are there? I'm sure every one of them will be met with derision from some other user.

> Kit installation manual is incomplete.

Yes. Yes it is... It is a work in progress. And I am about to launch a YouTube channel with build info and new product releases. I can only say it will come better with time. I wanted to get the new TEC-1G out before 2023 was over as that was the 40th anniversary of the original TEC-1. And yes, as such the documentation is being made AFTER the release of the product. Not ideal, I know. But then the target market was our existing TEC-1 users that are quite comfortable with building one of these up without much more than a schematic.

> It is important to read the errata sheet before building the kit.

Not sure how that is a Con

> Some of the changes in the errata had been made to the board but not all.

I would have thought that would be a Pro, not a Con. Go figure. And no I can't do the last part of the bodge wire, because that can only be done AFTER all the rest of the soldering is done. And that's not a part of the service, sorry.

> The 2 switches for selecting the monitor don't fit properly without having to reshape the pins.

Yes, they were originally made to be just jumpers, but I threw some switches that are not quite slim enough. Next edition of the board will fix this.

> The large oscillator switch can obstruct the key caps.

I honestly didn't think so, but noted. I'll see if I can move it a bit further "north" on the next version of the board.

> The power switch is flaky.

Not going to argue there. And it was a PITA finding that switch! The next version of the board will lose the USB-B connector which is the reason we had to go to DPDT. So that means we will be able to use a single pole switch; a right angled version of the speed switch which is way more robust.

> The 5 volt linear reg runs hot but is not out of spec. I would recommend using a modern regulator instead.

Not arguing with that... But again, not sure how that is a Con. If I put in an expensive Bucky, the cost of the kit would have been $5 more, and a lot of people are quite price sensitive.

> My kit briefly had issues with missing characters on the LCD but has not been seen since. I am not the only person to observe this.

Yes, we think we have found the source of the problem and it seems to be the actual LCD display. I'll be making a video about it.

> The magazine examples at the Github page do not work with Mon3

The magazine examples are from the original TEC-1 and if you boot the ROM into the MON-1B, those examples do indeed work. We have thankfully a really kind TECian that has only just recently spent the time on this "2 Star Kit" to convert all the programs for use with MON3. And that's the kind of nice people the TEC-1 brings into the fold, willing to dedicate their time and give back to the community for the benefit of all, because this "sub-standard" little computer is so lovable and easily accessible. (Checks notes...) Oh wait... That was you?? Well, thank you, good sir! :) And thanks for letting us add them all to the GitHub. Will do that shortly. I want to attribute the effort to you, but I'm not sure what to call you; By your name on Tindie or your name in Facebook? Let me know. :)

> The magazine examples are poorly commented

Mmm... They may be poorly commented in the Assembly listing, but you have to remember they came from listings of Code written up in magazines printed 40 years ago. And as such there ARE explanations of the code in those magazines. You have to remember these were created BEFORE the advent of assemblers or even connecting the TEC-1 to a computer for serial download. Everything was entered "on the metal" in raw Hex assembly code. Doesn't get any more real than that, brother. :)

> Expansion board/TEC deck options are limited.

Really?? I have FOUR extra kits available and listed in my shop for the TEC-1G, and I'll note you didn't buy any of them. I think they cover a pretty good range but sure, there is always more that could be made... But that's the beauty of this platform; NOT everything is already designed, meaning there is scope for YOU to design something and add to the ecosystem! (Didn't you mention you were going to make a Z80Bus to RCBus adapter? There you go!) Not up to designing hardware? Well feel free to jump onto the Facebook (or Reddit) group and suggest something you would like to see. Maybe another user might take up the challenge, or I might put it on the list of things I will make. In fact there is a new add-on about to be released that I think everyone will really love: the 8x8 LED Matrix display. Keep an eye out for it.

Well, I hope I have addressed all your concerns Fred/Gary. Bit of a harsh review considering you're already contributing to the ecosystem which speaks higher than the 2 Stars you have given it. It hurts, man... Cuts deep! :(