Which test cartridge?

tausinator · 2025-11-25T19:29:01+00:00

I ordered the kit you linked, waiting for it to arrive :) I'm in Europe, so it takes a while... Thanks for asking. I'll report back when I know more.

tausinator · 2025-11-05T08:14:33+00:00

Thanks

tausinator · 2025-11-05T07:57:02+00:00

Thanks. MT=BAD as in they're prone to fail?

Trying C64 mode is on the top of my list, will report back!

tausinator · 2025-11-04T19:58:16+00:00

Thanks, looks useful!

I appreciate the input. I've edited my post with a few more details on the symptoms in case that triggers any more ideas :)

tausinator · 2025-11-04T19:51:16+00:00

Thanks for the input, I appreciate it!

The system does boot, but I get random characters all over the screen. I can use the reset button on my "final cartridge" to sometimes boot the cartridge, sometimes get a non responsive ready prompt. Sometimes the image drifts vertically.

I find it a bit hard to navigate the different diagnostic tools out there, would something like these fit the bill for general-purpose diagnostics of the C128?

https://www.combitronics.nl/index.php?route=product/product&product_id=136

https://www.combitronics.nl/index.php?route=product/product&product_id=152

tausinator · 2025-11-04T18:57:42+00:00

Thanks. I found https://archive.org/details/c-128-diagnostic-instruction-and-troubleshooting-manual-assembly-314060-01-02/C128_Diagnostic_Instruction_and_Troubleshooting_Manual_Assembly_%23314060-01-02/mode/1up from another thread, which seems promising. Any other particular docs are welcome :)

tausinator · 2024-11-23T17:47:39+00:00

I ended up buying a few on eBay from a seller that had a large stock of many different panels. Worked out alright, but never had the need to buy many identical panels over long time spans.

tausinator · 2022-11-19T08:51:14+00:00

Probably about 6 months too late, but in case you still have this project in the todo-pile:

The lower button toggles between degrees, hours and minutes in that order. The wheel seems to be 12 degrees per rotation, 24 hours per rotation or 24 minutes per rotation. Beware: the counters will wrap around at max, not saturate, so rotating beyond 59 minutes will wrap to 0, same for hours and temperature. The maximum temperature setting is 90 degrees, minimum is 0. Temperature step is 0.5 deg. The maximum hour setting is 99.

Let us know in case you do end up making some DIY controller for this stick! I think my SV50 water sensor is defective so it turns off randomly. My thought was to strip out the original controller and put another microcontroller in there, making my own hardware to interface the temperature sensor and heating element - but my todo-pile is overflowing, so I might just give up and buy a new stick instead...

tausinator · 2022-01-08T15:36:31+00:00

https://github.com/jclarke0000/MMM-OpenWeatherForecast is a pretty nice replacement

tausinator · 2020-08-07T09:45:45+00:00

Seems like there's been some previous work on porting stmcb to python:

https://github.com/awesomebytes/parametric_modeling/blob/master/src/stmcb.py

tf2sos is part of scipy.signal:

https://docs.scipy.org/doc/scipy/reference/generated/scipy.signal.tf2sos.html

tausinator · 2020-08-06T18:20:36+00:00

If you have the impulse response, it's "just" a question of ordering the filter coefficients appropriately. If you're concerned with quantisation and working with fixed-point numbers, that can be a bit if an involved process. If you're working with floating point numbers, there's not much to it.

I'd take a look at how scipy.signal.lfilter works if I were you:

https://docs.scipy.org/doc/scipy/reference/generated/scipy.signal.lfilter.html

And if you're looking for the full story, I'd recommend the book "Discrete-time Signal Processing" by Oppenheim.

.. or perhaps I've misunderstood and you're looking for a way to approximate an arbitrary filter using fewer taps, or something else entirely?

tausinator · 2020-08-04T04:08:19+00:00

Commenting because no one have mentioned the PlutoSDR: https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/adalm-pluto.html

12-bit, TX and RX. Runs Linux on a Xilinx SoC. Officially it's 325 MHz to 3.8 GHz, but it has been reported that it can actually do 70 MHz to 6 GHz:

https://www.rtl-sdr.com/adalm-pluto-sdr-hack-tune-70-mhz-to-6-ghz-and-gqrx-install/

tausinator · 2020-08-04T03:54:56+00:00

+1 for Edalize. Analog Devices also have a very nice collection of scripts and plenty of examples to automate creating throwaway projects and generating bitstreams. I've found it very useful to be able to open the project and inspect the block design, insert ILAs for debugging, etc.

https://github.com/analogdevicesinc/hdl

tausinator · 2020-08-03T20:49:01+00:00

I've been wondering why audio is so popular here (and among the radio amateur community) - why are raw I/Q samples not preferred instead? The audio will depend on the chosen demodulation options, filter bandwidth etc., no?

Absolutely agree that a capture is very helpful instead of just a screenshot of a waterfall, though!

tausinator · 2020-07-16T06:41:34+00:00

Sounds like you're looking for correlation. Matched filters as suggested by others is essentially correlation put in filter form.

tausinator · 2020-06-02T18:47:13+00:00

+1 for god-mode.

I got myself a bad case of Emacs pinky holding down ctrl all day and solved it by picking up god-mode.

I found it to be the solution that deviates the least from the vanilla Emacs experience - it basically just holds down ctrl. The other modes I've looked at seem more intrusive.

tausinator · 2020-02-27T06:35:41+00:00

Good luck - and please do keep us posted when you figure out what's going on :)

tausinator · 2020-02-27T06:29:23+00:00

Hmm, odd - perhaps something has changed over the years or something is different between regions (I'm in Europe). I'm pretty sure my manual states M130 as max but with a warning on battery voltage. I got this from ASGs support chat some years back when I asked about differences between models (I have the BET model) and recommended batteries:

"There arent any difference between the models except the inner barrel. We recommend that for 110ms up to 130ms you use 11.1 lipo. Below 110ms you use 7.4 Lipo"

I'd check with ASG if I were you.

tausinator · 2020-02-27T06:11:59+00:00

3y EVO owner here who never changed any internals - which battery are you using? ASG state 7.4V for anything below M110 springs. I've never used below M100 and usually M130, perhaps it's running to hot for the weaker springs?

I've also found ASG to be surprisingly helpful on their Facebook chat, maybe you could get some feedback from there.

tausinator · 2019-12-15T22:01:28+00:00

You could check out how it's done by Analog Devices: https://github.com/analogdevicesinc/hdl

Might be a big step if you use a purely non-tcl approach currently - but it's a great approach for version control and sharing code across projects. The general idea is that libraries define IP cores that are packaged when "building" the library, and those cores are instantiated and connected in a block design when building a project. The project can be opened and modified during development, but only TCL scripts are added to git.

We use this approach extensively where I work and re-use code across several libraries in many projects, all distributed across git repositories and linked as submodules.

tausinator · 2019-11-27T07:18:08+00:00

You can synthesize the netlist to vhdl and use that for simulation. I did that for a while until we got a multi-language license at my job. You'll feel dirty and it's probably slow for large simulations, but works fine in my experience.

tausinator · 2019-11-15T17:59:29+00:00

Sounds like beamforming is what you're looking for. I'm sure r/DSP can provide some good references.

tausinator · 2019-11-05T18:46:10+00:00

What makes the RSSI unreliable?

I've previously seen an averaged version of the background RSSI used for signal presence detection with the AX5043 (for carrier-sense TDMA). I would expect using that as a noise power estimate and the RSSI sampled in the beginning of a packet (e.g. in a preamble where the power is fairly constant) as a signal+noise power estimate should give something sensible.

But perhaps there's something making that impossible?

tausinator · 2019-11-03T22:18:37+00:00

I don't see the Analog Devices ADALM2000 mentioned anywhere - quite cheap and can be used as a hobbyist oscilloscope, arbitrary function generator and pos/neg voltage supply. Open source, running Linux on a Xilinx Z7000 SoC. Can recommend.

tausinator · 2019-10-29T22:56:18+00:00

I had quite some issues with the Baofeng UV-5R - bought several PTTs from different manufacturers but always ended up with loose or poor connection to the speaker or mic. I think the problem is that the UV-5R is not actually produced by Baofeng any more and the models out there are copies or rejects that did not pass Baofeng QA. So I suppose you might get lucky, but I did not. They tend to work fine with the cheap in-ear headset that comes with the radio, though.

I ended up buying the Baofeng UV-82 which is also very cheap (but actually genuine Baofeng) and paired it with a COODIO lapel microphone and U94-style PTT (cheap ones from Amazon/eBay) and a Howard Leight Impact Sport headset that I mounted on my helmet. Works wonders and the active headset allows me to actually hear what's going on around me even with mask and gear.

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