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Test Equipment / Re: Agilent 54845A Failing all trigger self tests
« Last post by ARF on Today at 05:05:30 pm »Presumably this is so, but there are probably errors there.
Recent Posts
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Test Equipment / Re: Siglent SDS800X HD 1Specifications
« Last post by martinot on Today at 05:01:06 pm »Just put an order for a SDS804X HD scope. 
Seems out of stock in Europe, but hope I will get delivery in a month or so.
The new one is great!
I have two (one to use, and one as spare). You can find more info about the reissue here:
https://hpcalcs.com/product/hp-15c-collectors-edition/
Seems out of stock in Europe, but hope I will get delivery in a month or so.I did not know there was a HP15C collector's edition. I am still using on a daily basis, my original 15C, now going on 42 years.....
The new one is great!
I have two (one to use, and one as spare). You can find more info about the reissue here:
https://hpcalcs.com/product/hp-15c-collectors-edition/
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Projects, Designs, and Technical Stuff / Re: Suggestions for secure authentication solution?
« Last post by mikeselectricstuff on Today at 04:59:10 pm »Is there any need for sort of 'root level' authentication, like to prevent other devices from pairing if someone happens to reverse engineer the algorithm?no - the general idea of good security is that teh algorithm can be public, only the keys need to be secure
Quote
Looks like there are a few appnotes for this chip that may be relevant - need to read those.
There are crypto ICs that support ECDH, for example microchip ATTEC608, which should make it fairly easy to get wire-level encryption to exchange a shared key during the pairing process.
My initial feeling is that the "usual" way these are used is by some kind of factory provisioning process to generate keys, whearas what I need is something where random keys are generated and exchanged in the field at installation.
I'm sure this is possible but I'm out of my depth in crypto-jargon at this stage and need to figure out the appropriate jargon for what I'm trying to do.
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Beginners / Re: buying a oscilloscoop
« Last post by Wallace Gasiewicz on Today at 04:58:29 pm »Look at the o scope tutorial at the top of this forum, when you get through it you will know what you need.
drdm is correct. For most repairs 2 channels is plenty. I very seldom even use two in repairing radios and audio stuff.
I used to be a fan of old CRT scopes but they are getting old and usually require repair. The older digital scopes are not great, newer ones are much better. When you have done more research, perhaps others can help with their experience with newer digital scopes. There are a lot of reviews in the Test Equip Forum.
When you need to analyze many channels it is frequently when you are looking at logic circuits.
Some scopes have logic analyzers built in but...If you need to analyze logic outputs there are relatively inexpensive logic analyzers available, these can show you many more channels.
drdm is correct. For most repairs 2 channels is plenty. I very seldom even use two in repairing radios and audio stuff.
I used to be a fan of old CRT scopes but they are getting old and usually require repair. The older digital scopes are not great, newer ones are much better. When you have done more research, perhaps others can help with their experience with newer digital scopes. There are a lot of reviews in the Test Equip Forum.
When you need to analyze many channels it is frequently when you are looking at logic circuits.
Some scopes have logic analyzers built in but...If you need to analyze logic outputs there are relatively inexpensive logic analyzers available, these can show you many more channels.
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Test Equipment / Re: Magnova oscilloscope
« Last post by moerm on Today at 04:56:14 pm »R&S were founded 90 odd years ago, & have been making test equipment from the beginning.
They have been heavily involved in high level radio comms & broadcast/TV equipment & TE for both fields for 70 plus years.
Far from "some kind of", their equipment has been always regarded as "top-tier" (and with a price to match!).
They weren't makers of Oscilloscopes till relatively recently (although even that is now a decade plus).
My point wasn't to bash R&S. I know that they are considered as among the best in RF. But I also know that I've definitely seen quite some TME with a R&S label on it that was produced by a japanese company. Whatever, this thread is about a scope, so that, R&S scopes, is what I focused on. And in that field I would, although formerly a fan of R&S, absolutely not buy one of their scopes after the RTM clusterf_ck. Also, as an add on, I consider a company building scopes with a glossy screen as insane and evidently not guided by engineering and rationality. It seems though that their higher end scopes don't have glossy screens. Maybe they just assumed that those who buy their lower end scopes would be attracted by something glossy; if so they'd certainly not be alone in that.
Quote from: ebastler link=topic=422984.msg5456345#msg5456345
I did not attack you either. Although I must say that I found your first post a bit too long, too opinionated, and too ripe with strong language.
But you are clearly not a "potential customer" and have made that very clear through the requirements and preferences you stated. That's what I wanted to point out.
Well, that's your perception and interpretation and I accept it as such.
- Yes, you are right, I'm not a potential customer and I explained why. Unlike how some (wink wink nudge nudge) paint it, I did however bash neither Batronix nor their scope. I simply and frankly stated my position. Which, in fact is a service to them. I'll say it in the words of a restaurant owner with whom I later became friends: "(constructively) criticizing us is very important for us. There is nothing worse for us than what many unsatisfied customer do; they smile politely, leave, and never return. With criticism we at least learn what customers don't like and can change, adapt, improve".
And I sincerely tried to be fair and to mention the positive as well.
That said, I admit that I'm probably a "difficult" customer, because I try to be properly informed, to know what I want/need and what not and in which order of priority. Plus, I'm seriously allergic to marketing blabla. In other words, it takes a lot for me to like a scope, SA, multimeter or whatever, let alone a brand.
Friendly greetings
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Test Equipment / Re: LeCroy WaveRunner 606Zi starting only every Nth try
« Last post by Martin72 on Today at 04:55:41 pm »Quote
And could a bad C-MOS battery really prevent the scope from powering up?
Absolutely:
https://www.eevblog.com/forum/testgear/lecroy-hdo6034a-wont-boot-anymore-fixed/msg5180832/#msg5180832
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Beginners / Re: Signal generator question
« Last post by CamJam on Today at 04:52:26 pm »Thank you for the informative reply, RoGeorge!
To reassure you a little, I wear UV blocking face shields, a lab coat, and gloves while operating any UV LEDs.
Thank you for correcting my original interpretation that I could run the 10 mW LED with the function generator and confirming that I need a transistor driver to properly modulate the 18 mW LED
Appreciate the reminder, I am aware of the polarity issues, I always double check with a multimeter!
The LEDs I am using are surface mount LEDs with 3 pads, an anode, cathode, and heat sink. Thankfully no need for a control loop (unless the heat sink is the "optical feedback diode"). If you have any insight on how to properly accommodate the heat sink pad of the LED I am all ears. (will look elsewhere on the forum for this info as well.)
I am currently planning on just having the heat sink pad soldered on a relatively large area of copper/metal to help with heat dissipation.
To reassure you a little, I wear UV blocking face shields, a lab coat, and gloves while operating any UV LEDs.
Thank you for correcting my original interpretation that I could run the 10 mW LED with the function generator and confirming that I need a transistor driver to properly modulate the 18 mW LED
Quote
- Beware at the LED polarity, they got damaged easily if you connect them in reverse.
Appreciate the reminder, I am aware of the polarity issues, I always double check with a multimeter!
Quote
- Beware of the LED with 3 pins (with optical power photodiode included), they got damages if the optical feedback diode is neglected. For those 3 pins "LEDs" you'll need a dedicated control loop if you want the max power without damaging the LED.
The LEDs I am using are surface mount LEDs with 3 pads, an anode, cathode, and heat sink. Thankfully no need for a control loop (unless the heat sink is the "optical feedback diode"). If you have any insight on how to properly accommodate the heat sink pad of the LED I am all ears. (will look elsewhere on the forum for this info as well.)
I am currently planning on just having the heat sink pad soldered on a relatively large area of copper/metal to help with heat dissipation.
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Repair / Re: Keithley 195 stopped working after a lightning strike near my house.
« Last post by Kleinstein on Today at 04:52:18 pm »A lower power consumption is possible for the newer chips. 60 mV difference may also be thing from a different temperature.
I would not expect EPROMs to be especially sensitive to loosing it content from a glitch. AFAIK they are not especially sensitive.
If one has a scope, one could look at the data / adress bus to see if the CPU is running or somewhat stuck. If stuck the clock and reset signal are further points to check.
The signal quality at the bus could also show if there is a bus conflict (usually causes intermediate signal levels).
I would not expect EPROMs to be especially sensitive to loosing it content from a glitch. AFAIK they are not especially sensitive.
If one has a scope, one could look at the data / adress bus to see if the CPU is running or somewhat stuck. If stuck the clock and reset signal are further points to check.
The signal quality at the bus could also show if there is a bus conflict (usually causes intermediate signal levels).
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Vintage Computing / Re: MVME-110 EPROM monitor program
« Last post by LittleFrog on Today at 04:48:35 pm »Thanks Marc. I just couldn't leave the job half done so I found (what I think was) the problem, wrote up the notes and now I really am going on holiday. I don't know exactly what I did wrong first time, but I have a strong feeling that it was a school boy error which I refer to vaguely in the notes....
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General Technical Chat / Re: Post a picture of a cat!
« Last post by TheSteve on Today at 04:48:08 pm »Boomer scans the Flora for some Fauna during a weekend park trip.
