I’m feeling I need something like that in my life. There was a racal counter listed earlier. Not that though
Mmmmm... Nixie goodness!
Yup; in two forms, filtered and unfiltered as per https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg4244440/#msg4244440
The more I use the the less I dislike them, which doesn't bode well for my flipping them
Interesting how they filtered one to orange, and the other to red. Is the red one a newer instrument? Perhaps aiming to mimic red LEDs if they were contemporary to it?
I’m feeling I need something like that in my life. There was a racal counter listed earlier. Not that thoughWas gunna say go walk it off to regain some sanity then remembered you broke yourself last weekend, right ?
I’m feeling I need something like that in my life. There was a racal counter listed earlier. Not that thoughWas gunna say go walk it off to regain some sanity then remembered you broke yourself last weekend, right ?
Yeah true
Still broken as well
I’m feeling I need something like that in my life. There was a racal counter listed earlier. Not that though
just wanted to say thanks to vince and mnem for providing information and motivation to help investigate the hp 54657a measurement/storage module.
noodled around with my hp 54601a and found the following:
the time and date functions work fine when the scope is powered up but get scrambled after powering down and restarting.
conclusion - the battery in U7, a dallas ds1244y-120 (32k x 8 and clock) .......is dead. (1992 date code)
the 99 waveform trace and set up memories work fine when the scope is powered up but are all gone after powering down and restarting.
conclusion - the battery in U8, a dallas ds1245y-120 (128k x 8 )........ is dead. (1992 date code)
all of the fancy measurement and waveform math features to include fft are still working.
conclusion - the firmware for those features is in the am27c2048 rom (128k x 16).
so am i gonna' mess with the nvram chips just to timestamp and store waveforms inside the box. hell no.
I beg to disagree !
As you saw my serial // module does NOT have an EPROM, only the two NVRAM chips and that's it ! Yet as the manual states, all modules give access to 100% the same extra features.
So as was discussed earlier here, the F/W must be in one or two of the NVRAM, unlikely as it's silly from an enginerring point of view + yo need that RAM space to store all the waveforms and their metadata like time stamps. Need space for the mask feature if you use that. So the most likely solution here as as suggested is that the code for these extra features is already in the scope itself, on the main board, and the module NVRAM chips just provides the RTC and user data storage space.
So, the EPROM chip in the GPIB module is most likely there to support the GPIB stuff itself.. probably because there was enough ROM space left on the scope mainsboard because... they filled it to the top in order to cram the extra module features into it.
That's my best guess so far.
Once my lab is computerized + chip programmer + desoldering gun ... I will start playing this thing. Remove the two NVRAM chip to read them to confirm there is no code in there.
I bet if you read that EPROM in your GPIB module you would see only GPIB related stuff, but nothing about all the extra features that all these modules implement...
why would they put the math feature firmware on the main board and then not turn it on until you bought the extra back side module?
(edit either way.....the extra feature firmware is in rom somewhere and not in nvram. so i am not gonna try to dissect those damn things and wire in external batteries)
am looking forward to someone reading the data off those chips (not me!) and deciding this issue.
... .... we derived a crossover mapping which was programmed into the system based on the spectrum analysis at the listening position.it was worth every penny.
Cheap Teledyne (Siglent rebranded) scope on ebay this morning. Brand new, 275$. 2 ports 100Mhz 2Gs/s 140MPts. Can be upgraded to 300Mhz
https://www.ebay.com/itm/165537662690
I’m feeling I need something like that in my life. There was a racal counter listed earlier. Not that though
Think of them as being like redheads... Pretty but mostly unreliable.
if the marten which sneaked in howls in agony and leaves, then it was tuned quite right.
I’m feeling I need something like that in my life. There was a racal counter listed earlier. Not that thoughWas gunna say go walk it off to regain some sanity then remembered you broke yourself last weekend, right ?
Yeah true
Still broken as well
Cheap Teledyne (rebranded Siglent) scope on ebay this morning. Brand new, 275$. 2 ports 100MHz 2Gs/s 140MPts. Can be upgraded to 300MHz
https://www.ebay.com/itm/165537662690
Got the motivation to have a look at the ADVANCE J2E oscillator I have that's taken a step backwards - it has no output at all now. However, since it's a valve based unit (and I've not worked on valve gear for quite some time) I wanted to get a schematic with at least some voltages on it. All I've found so far is the same scanned images of the manual, presented in different wrapping. It has a component list and a schematic ... without a single voltage or waveform. Will be doing a close visual inspection before powering up.
What I did come across, however, was this little gem: eBay auction: #154458177121
Just .... wow.
Cheap Teledyne (rebranded Siglent) scope on ebay this morning. Brand new, 275$. 2 ports 100MHz 2Gs/s 140MPts. Can be upgraded to 300MHz
https://www.ebay.com/itm/165537662690
Ehhhhhhh.... might be worth taking a punt at that price. Weird feedback, tho there do seem to be plenty who actually get their stuff as well.
mnem
I’m feeling I need something like that in my life. There was a racal counter listed earlier. Not that thoughWas gunna say go walk it off to regain some sanity then remembered you broke yourself last weekend, right ?
Yeah true
Still broken as wellThat seems to happen a lot these days, maybe your body is actually trying to tell you that you are overdoing these hikes and if you must persist, to do shorter ones?
EDIT: Wait....what...? According to their Storefront, this is the LeCroy factory outlet store (member since 2001) in the US:
https://www.ebay.com/str/teledynelecroy?_trksid=p2047675.m3561.l2563
mnem