Zenith ZKB-2 not working

[Wazrach]

Hi guys, I recently purchased a ZKB-2 in great condition, although the seller described how it would not work with his Soarer's converter. He said it would not send scancodes. I thought I would try AT > PS/2, just in case this is like the AT Z-150. That doesn't work either. The beeper goes off when plugged in, but of course none of the keys work.

I took it to a computer repair shop near me, and the guy looked at the large "chip" at the right side of the controller, saying he wouldn't be able to fix the keyboard because of it. I'm not sure what he meant or why, as I know absolutely nothing about this kind of thing.

Is there anything I could try? Is one of the components on the controller dead? If you need to see pictures, I'll have to email them to you or something. I cannot upload pictures on DT or create an Imgur account, it's extremely frustrating. I've even tried on my phone - STILL won't work.

Thanks in advance.

[Chyros]

Hiya mate, first thing to check would be the AT/XT switch located underneath the ZDS badge. Check what position it is in, and whether it is not so corroded that it makes an erroneous contact.

[//gainsborough]

Sounds like the controller is damaged - so you'd need a new controller chip or a another PCB, which puts you in the same boat I'm in: needing a new ZKB-2 PCB.

[ZedTheMan]

Sounds like the controller is damaged - so you'd need a new controller chip or a another PCB, which puts you in the same boat I'm in: needing a new ZKB-2 PCB.

I think I've seen a couple of auctions for some ZKB-2s in really rough physical shape that just went up. Maybe the PCBs are good and you can harvest them and anything else that might be of value.

[abrahamstechnology]

Replace the electrolytic capacitors first. It it still won't work perhaps you could wire up a Teensy2.0++

[//gainsborough]

I think I've seen a couple of auctions for some ZKB-2s in really rough physical shape that just went up. Maybe the PCBs are good and you can harvest them and anything else that might be of value.

Yeah I saw those too, but it looked like the cables were cut. I'll have a look again, though!

[ZedTheMan]

Cables are cut, but, it's not like you can't connect the cables of your original one.

[//gainsborough]

that's true - I could do that. It'll probably look terrible, but that is definitely an option!

[ZedTheMan]

Why would it probably look terrible? Were there different revisions of the cable that would clash?

[//gainsborough]

No no, I mean that I'm not very good at splicing cables. I could, desolder the cable from the PCB and then solder the working cable in it's place and cover it with electrical tape or something, that might not look too bad. I still don't know why zenith soldered the cable wires directly into the board instead of using a removable cable clip thingy. If memory serves, not even the z150 had a PCB design like that. Makes no sense to me.

[Wazrach]

Hiya mate, first thing to check would be the AT/XT switch located underneath the ZDS badge. Check what position it is in, and whether it is not so corroded that it makes an erroneous contact.

Hi Thomas, thank you. I am able to switch between AT and XT just fine, although I don't know if either modes actually work or not for obvious reasons.

[Wazrach]

Sounds like the controller is damaged - so you'd need a new controller chip or a another PCB, which puts you in the same boat I'm in: needing a new ZKB-2 PCB.

I'm eyeing up the dirty ZKB-2 with Yellow Alps and missing keycaps on Ebay right now, although I don't think the international shipping would be worth it. Is that the only way I could replace the chip?

[Wazrach]

No no, I mean that I'm not very good at splicing cables. I could, desolder the cable from the PCB and then solder the working cable in it's place and cover it with electrical tape or something, that might not look too bad. I still don't know why zenith soldered the cable wires directly into the board instead of using a removable cable clip thingy. If memory serves, not even the z150 had a PCB design like that. Makes no sense to me.

I find it strange how they soldered the cable directly to the PCB as well. Never seen that before. I bet it would look gorgeous with a black badge and Model F XT black cable!

[Wazrach]

Replace the electrolytic capacitors first. It it still won't work perhaps you could wire up a Teensy2.0++

I wouldn't know where to start with this. Is there a guide I can use?

[Tias]

@Wazrach
Here's one ZKB-2 currently for sale.
https://rover.ebay.com/rover/0/0/0?mpre ... 3719821374

Looks pretty beat up though, quite rusted and the whole keyboard looks bent. I'd imagine this board would go for a quite cheap price and perhaps the PCB would be usable.

Hopefully you'll get yours working

[Wazrach]

@Wazrach
Here's one ZKB-2 currently for sale.
https://rover.ebay.com/rover/0/0/0?mpre ... 3719821374

Looks pretty beat up though, quite rusted and the whole keyboard looks bent. I'd imagine this board would go for a quite cheap price and perhaps the PCB would be usable.

Hopefully you'll get yours working

Yeah that's the one I was looking at, but thanks anyway! Probably won't be worth it considering I am in the UK.

[Wazrach]

@Wazrach
Here's one ZKB-2 currently for sale.
https://rover.ebay.com/rover/0/0/0?mpre ... 3719821374

Looks pretty beat up though, quite rusted and the whole keyboard looks bent. I'd imagine this board would go for a quite cheap price and perhaps the PCB would be usable.

Hopefully you'll get yours working

Yeah that's the one I was looking at, but thanks anyway! Probably won't be worth it considering I am in the UK.

Plus, if I can help it, I'd rather not have to replace the whole PCB. It would be great if I could just replace some controller components.

[Evan]

Is it possible that there is an issue with the data wires in the cable?

[Tias]

@Wazrach
Here's one ZKB-2 currently for sale.
https://rover.ebay.com/rover/0/0/0?mpre ... 3719821374

Looks pretty beat up though, quite rusted and the whole keyboard looks bent. I'd imagine this board would go for a quite cheap price and perhaps the PCB would be usable.

Hopefully you'll get yours working

Yeah that's the one I was looking at, but thanks anyway! Probably won't be worth it considering I am in the UK.

Plus, if I can help it, I'd rather not have to replace the whole PCB. It would be great if I could just replace some controller components.

Oh, I didn't think about the fact that you where based in the UK x) In that case, as you mentioned, the total cost of the board with included shipping, taxes and whatnots would probably be way to high to even consider buying it. Especially when you have no idea whether or not the PCB is actually usable.

[abrahamstechnology]

Replace the electrolytic capacitors first. It it still won't work perhaps you could wire up a Teensy2.0++

I wouldn't know where to start with this. Is there a guide I can use?

Ask snacksthecat, he's done it with a lot of boards.

[snacksthecat]

I think it would probably be best to investigate a bit more why the keyboard isn't working right now before resorting to replacing the controller. Just because doing that is so time consuming and once you start, you're committed.

I don't see it mentioned a lot but Soarer also wrote a pretty cool "simple logic analyzer" firmware that can provide some troubleshooting information.
Simple Logic Analyzer for Teensy

To use it...

Flash the firmware

1. Download sctrace_v1.01_ATmega32U4.zip from the link above
2. Flash the file sctrace_v1.01_portD_ATmega32U4.hex to your Soarer's converter

Generate some data

1. Download hid_listen
2. Open a command prompt and launch hid_listen
3. Plug in the keyboard and hit some keys

You should see some output in hid_listen. If not, that would indicate a problem.

Visualize the data

1. Download scla_v1.00_win32_exe.zip from the link above
2. Open a command prompt and launch scla.exe
3. Copy the output of hid_listen and past it into scla

You should see a visualization of the output data.

[Wazrach]

I think it would probably be best to investigate a bit more why the keyboard isn't working right now before resorting to replacing the controller. Just because doing that is so time consuming and once you start, you're committed.

I don't see it mentioned a lot but Soarer also wrote a pretty cool "simple logic analyzer" firmware that can provide some troubleshooting information.
Simple Logic Analyzer for Teensy

To use it...

Flash the firmware

1. Download sctrace_v1.01_ATmega32U4.zip from the link above
2. Flash the file sctrace_v1.01_portD_ATmega32U4.hex to your Soarer's converter

Generate some data

1. Download hid_listen
2. Open a command prompt and launch hid_listen
3. Plug in the keyboard and hit some keys

You should see some output in hid_listen. If not, that would indicate a problem.

Visualize the data

1. Download scla_v1.00_win32_exe.zip from the link above
2. Open a command prompt and launch scla.exe
3. Copy the output of hid_listen and past it into scla

You should see a visualization of the output data.

Thank you for that, I will keep it in mind. I don't have the keyboard on me right now, but when I get back to working on it, I will let you know how it goes!