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1
Adding a few parts parts is not hard - assuming pads already have solder from the original paste, plenty of flux, and reflow with hot air.
2
Test Equipment / Re: HP 3478A behavior on low ranges
« Last post by adam4521 on Today at 09:07:14 am »
I just saw in the pyvisa docs that there is a pure python implementation as well (pyvisa-py), maybe that would be enough. It might depend on what type of interface cable you have got.
3
Buy/Sell/Wanted / FS: Tektronix 2465B
« Last post by hpw on Today at 09:07:07 am »

Selling the IMHO working Tektronix 2465B.

Sell as parts for 170 Euros, while no warranty and no returns.

Changed so far as required:

- the X/Y 240V caps as for 400V
- added the cooling for the special chip
- changed the plastic grid as now as new.
- Also with a cover protection bezel.

I will add 3 probes for free as 2 complete one as special for direct measurement's.

IMHO in very good condition as no smoking environment and used as a professional user.

Additional Packaging costs (as needed) and shipping costs as needed or liked.

Shipping from Island Canary

Any interests as by PM please.

Hp

4
Repair / Re: Help me to find Diode "14" mark datasheet
« Last post by artag on Today at 09:04:52 am »
Those are all 3-terminal devices though - regulators etc.
Assuming it's 2-terminal it might be an SS14.

5
How old? After decads the LCDs all fail.

j

That's an issue of 70s LCDs, mid 80s rarely fail (in my experience).
This is from 1985. So it survived for almost 40 years, unlikely to fail in the next months, I guess.
6
Microcontrollers / Re: Mcu programming 101 writeup
« Last post by wek on Today at 09:02:27 am »
Thanks for the comments.

@brucehoult, "flashing" sounds good, will rephrase. Shall I do that also in the main text? "Device programming" sounds old, doesn't it.
Sorry for the errors in grammar. I don't think I can improve in that too much.

@tellurium, I see your point, and I beg to disagree. IMO the main thrill in mcu programming is the physical aspect ("see the LED blinking"). Remote debugging also adds "magic", which I propose to minimize at this stage. Don't get me wrong; I understand that there are merits in remote debugging.

JW
7
Test Equipment / Re: HP 3478A behavior on low ranges
« Last post by adam4521 on Today at 09:01:35 am »
Before changing the battery, you can read out your calibration constants if you have got a GPIB/USB cable. The feature is documented on the forum here:

https://www.eevblog.com/forum/repair/hp-3478a-how-to-readwrite-cal-sram

I've attached a python script I made a few years ago to extract the calibration. I haven't made the reverse one, but it would be easy enough to create that. Unfortunately the pyvisa module needs one of those gigantic VISA runtimes to be installed on your computer, in order to work. I think I used the Keysight one.

8
Quote
But of course the client does need to store their own private key. How otherwise would you authenticate the client?

Obviously you know the answer :)

The client accesses the server by doing a DNS lookup. Now obviously the DNS could be poisoned. But the client can be disassembled anyway and any private key extracted from it. There is no perfect solution, unless you put in a secure crypto module.

However one can add additional security within the comms, and normally one would even if TLS is used. For example firmware updates would have a hash on them, although again this is not secure from client disassembly.

Ultimately any single client can be messed with, but that's OK. What you really do not want to happen is somebody trashing the installed base of say 100k of them, or any significant part of it. And that seems fairly easy to do so long as the server is not penetrated. The next thing to do is set up the server so it does not contain a database of the installed clients. I think that is easy enough because the ultimate mutual authentication could be between the client and the customer's app trying to access it. The server's purpose can be just to facilitate the clients being, ahem, clients, all behind various NAT routers so they can't all be casually discovered.

I am sure many people have been around this before (it is a very common application) but they won't be posting the details here ;) But I also know that many don't bother; I recently stayed in accommodation where the heating was remotely controlled and the controller was a server and the router had port forwarding.
9
Thanks a million to professor Performa01.

This review book is so great, so I translated it into Chinese and published it on Zhihu (similar to Quora), and I have only completed 20% so far.
The main purpose is to learn for oneself, and it would be even better if other people could also learn about these oscilloscope knowledge.
If you feel it's not suitable, I will hide it.   ^-^
Thank you again.

The following English image is translated from Chinese to English through Google.
10
Yes indeed, your phase noise is better.
What is Samp detection in your screenshots ? Never used it  :-//
Quote
Now you have an SSA3021X+ and I'm not sure if it has the same hardware as an SVA1032X.
Instead be sure it does.

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