MS05000 Budget Logic Analyzer Probe Set Design

[lastguy]

Very nice! are these kit still available? if possible I want PCB and connectors. I might need to go back find how to order.
You used to mention to check whether 100M data works or try new chips, any update?
Another question, if scope set 3.3V logic, what is Vref output level? I know your design doesn't use Vref yet I still like to know thanks.

[Gandalf_Sr]

Sorry it's been so long with no posts - my eldest son died (aged 41) in Nov 2021 and I'm just getting back to something like normal. I do still have PCBs if anyone wants them but shipping to a non-US address is a pain.

However, I'm making a trip to London UK / EU leaving on Jul 27th so, if you want some PCBs, let me know and I should be able to post them in the UK/EU.

One thing I will say is that the chips are in crazy short supply and I do not have any spares.

[fjalvingh]

Oh Gandalf_sr, that is really terrible and sad news. I wish you the best in getting over that, and hope that picking up the hobby will help.

[mawyatt]

Dear Gandalf_Sr,

So very sorry about the loss of your son, and know somewhat about the pain of losing one's child. Having lost our oldest son 27 years ago and our youngest son last Aug (39), and our youngest daughter is in a horrible incurable state. A parent should never have to bury a child, and that stretches one's faith!!

If it helps, don't try and keep everything inside, there are others that have similar experiences that can help to talk with. I know, at first I've tried to keep everything inside and talking with others has helped a bit and gave me a better perspective on life in general.

Somehow electronics seems to be a momentary escape from the reality we've been unfairly dealt. Helps calm you down, and hope this can also be of some help for you.
Just "talking" with all the great folks on here with the common thread of electronics is kind of a therapy in itself, I know it's certainly helped and continues to help me get through all the difficulties that life has unfairly thrown our way.

Best wishes and condolences on the loss of your son.

Best,

[Gandalf_Sr]

Thanks for all your kind wishes, I'm OK (I think).

[lmamakos]

I assembled my boards today - 4 pods and the MSO plug-in board.  I built two each for each voltage range, because why not?  It's late, only done a smoke test and the LED's come on, so far so good!   I need to give them a good wash and then take them for a ride on my MSO5074.

The 3.3v LDO was unavailable, and I thought I had some others here already.  Turns out I had the wrong package, but managed to bodge it on there anyway..

[fest]

I considered adapting this design to use Vref from the MSO- providing Vcca with an amplified Vref voltage of gain = 16 should result in Vcca voltages very close to CMOS levels that are available as presets on the scope (e.g. when CMOS 1.8 is selected, Vref voltage is 112mV on my scope, after amplification Vcca would be 1.79V). The threshold levels wouldn't exactly match the indicated voltage on MSO, but appear to be close enough for the CMOS 1.2-5V ranges I'm mostly interested in). Of course, one must also limit the Vcca between 0 and max. level shifter's Vcca.

However, one important aspect to note is that SN74AXC8T245 has a propagation delay that depends on Vcc. With Vcca = 0.8V, Vccb = 3.3V the propagation delay is 0.5-35ns, which would limit it's operation at ~28MHz in the worst case.

SN74LXC8T245 which is advertised as faster than SN74AXC8T245, the LXC version appears to be worse at low voltages: at Vcca=1.2V, Vccb = 3.3V, SN74AXC8T245 has delay of 0.5-7ns, while SN74LXC8T245 has a delay of 5-22ns.

I briefly looked at high speed comparator design, but I didn't like what I saw (Rigol logic probe does not seem expensive anymore), so I'll likely take a stab at such a voltage-adjustable version and hope for the best (either of them seem to be ok for 1.8V at ~100MHz which is my immediate need).

[mtnzap73]

Hi Gandalf_Sr

Long time no message. Like about 3 years. I guess a pandemic has its effects.
I was looking to see if you are still able to send the stencil files.
The LA probe project sat on my shelf until now, and I am getting all ready to start it up again.
I did try PM like we were doing when I purchased the boards ....

Best regards,

Stan
Calgary

[mtnzap73]

With all respect, can I ask the forum the following:
> did anyone get and use the solder stencils?
> is there a way for me to get them?
> am I asking the question correctly?

[mtnzap73]

Hi Imamakos,

Nice to see your success.
I also have the kit and am getting ready to assemble it.

Did you obtain or use solder stencils?

[Gandalf_Sr]

Hey all, the stencils are already here in this thread, page 2

I am now retired and not very active on this thread; sorry for late replies to messages

[lmamakos]

Did you obtain or use solder stencils?

No, I just hand soldered all the boards with thin wire solder.

[LoveTheFactory]

Anyone tried this Logic Analyzer probe with with the new Rigol DHO800/900 line ? 

 @yGandalf_Sr, any boards left ? 

Thank you for sharing with us...

You are a awesome person. I like your style.  You help
us understand how we are supposed to act.

[Nikki Smith]

Anyone tried this Logic Analyzer probe with with the new Rigol DHO800/900 line ? 

I've made a different design that should work with the new DHO900. And I'm hoping to hack my DHO804 so it supports a logic analyser too 
https://climbers.net/sbc/clone-pla2216-logic-probe-analyzer/

[ebastler]

I've made a different design that should work with the new DHO900.

Just to clarify: Your design has various improvements (reduced via count, tidier dimensions, improved parts availability etc.) -- but none of these are required to make it work with the DSO900, right? I.e. the older designs should work as well, since the MSO5000 and DSO900 use identical logic analyzer connections? Thanks!