Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 1908283 times)

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Offline ArthurDent

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31150 on: May 11, 2019, 11:25:09 pm »
Kosmic (post #31124) -“Some weeks ago, I got another piece for my instrument collection from ESI. This time it's a SV-194B Voltage Calibrator.” ….”After some tests I realized the resistors had drifted though. Will need to find a solution for that.”

Are you sure the resistors have drifted? Here are the readings I get on my SV194 B without removing the resistors from the circuit. Some values are common, some aren’t but these resistors just don’t drift. The nine identical ones on the fuse side are all 40K and I have the ones across the bottom from right to left as 20K, 16K, 2K and 1.5922K The two up the other side are 1.038 ohms and 7.414 ohms. The four staggered ones from bottom to top are 200.13 ohms, 160.15 ohms, 20.172 ohms, and 20.172 ohms.
 
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Offline bitseeker

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31151 on: May 11, 2019, 11:31:25 pm »
Not TEA related (but certainly related to funding more TEA and a bigger house to put it all in  :-DD ), but I walked with my MS in Computer Science today.

Congratulations, 0culus! :clap:

Quote
Looking forward to working for a little while before possibly adding shit piled higher and deeper!  >:D

Ah, yes, TEA PhD. :-DD
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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31152 on: May 11, 2019, 11:33:44 pm »
The interesting bits related to my leopard and gharial. Took one to be repaired on the way from back from picking up some equipment; found I probably ought to insure them.

:-// What are those?  :-//

Google is your friend, and they aren't test equipment, nor are they still alive.

My mother's house is famous amongst the ambulance staff that attend her occasionally. Some might regard it as creepy, but apparently taxidermy is becoming fashionable again :)

I always rather liked it. Hence why we have a growing family of taxidermy mice that get rolled out once a year for Christmas as tree decorations. This also has the effect of causing emotional distress in my mother in law  :-DD

One is dressed up as a witch and has a little broom.

The smallest of my mother's taxidermy exhibits is a snake. The largest has appeared on stage at the Old Vic theatre :)

It isn't this , even if it feels like it at times :)
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline bitseeker

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31153 on: May 11, 2019, 11:41:19 pm »
A busy couple of weeks, with some good bits, some interesting bits, some disappointing bits, some irks, and a bloody annoyance.

...

Today I picked up an hp8562b 22GHz spectrum analyser for £350, sight unseen, then toddled across the country to pick it up from the auction house (it had to be picked up today or Monday, and on Monday I'm in another country. The irksome bit was that when picking it up I chatted to someone who had bought an Anritsu portable spectrum analyser, and he said it had been a bankruptcy sale. If I'd known that, I'd have bid on some other items, grrr.

The good news is that the hp8562b works :)

Wow, what a score!

Surely that helps offset some (most?) of the less desirable bits.
« Last Edit: May 11, 2019, 11:44:54 pm by bitseeker »
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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31154 on: May 11, 2019, 11:54:47 pm »
A busy couple of weeks, with some good bits, some interesting bits, some disappointing bits, some irks, and a bloody annoyance.

...

Today I picked up an hp8562b 22GHz spectrum analyser for £350, sight unseen, then toddled across the country to pick it up from the auction house (it had to be picked up today or Monday, and on Monday I'm in another country. The irksome bit was that when picking it up I chatted to someone who had bought an Anritsu portable spectrum analyser, and he said it had been a bankruptcy sale. If I'd known that, I'd have bid on some other items, grrr.

The good news is that the hp8562b works :)

Wow, what a score!

Surely that helps offset some (most?) of the less desirable bits.

Depends on whether you think the glass is half full, half empty, or twice the size it needs to be. There was also an hp8561b 6.5GHz SA that went for marginally less, and 300MHz-18GHz antenna I would have liked, and a portable SA, and a 20GHz counter, and some power probes, and some noise figure test sets and noise sources, and a 20GHz sweep oscillator, and... But I didn't realise it was a bankruptcy sale!

But yes, overall I come out ahead - partly because I buy things that interest me and don't buy things I can't afford to write off.

There's an old skiing proverb which I taught my daughter: if you aren't falling down ten times a day, you aren't trying hard enough. Then she broke her knee skiing, and couldn't become a solo pilot on her 16th birthday :(
« Last Edit: May 12, 2019, 12:00:24 am by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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Online PA0PBZ

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31155 on: May 11, 2019, 11:55:11 pm »
its not that I don't believe you,  but could you post pictures that would help to explain what the hell "taxidermy mice" are?

Keyboard error: Press F1 to continue.
 

Offline bitseeker

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31156 on: May 12, 2019, 12:01:50 am »
Tracking generator question:

I understand in general how they do what they do, however the page for the DSI TG6000 says that the indicated spectrum analyzers "without LO output option must be modified with a simple directional coupler." How does that work? I assume it has to be added inside the analyzer and then the LO signal brought out somehow.

The reason I ask is that my not-yet-arrived R3465 doesn't appear to have any LO output, yet it's not marked in the list of supported devices as lacking an LO output. Maybe just an oversight or am I not seeing where the LO output is?

If I can't easily add a TG, I suppose an alternative to modding the analyzer or buying a noise gen would be to sweep a sig gen with the spec an set to max hold. Should work fine for DUTs that don't change their characteristics over time. My first use for this would be to check out the flatness of some scope probes.

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Offline bitseeker

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31157 on: May 12, 2019, 12:05:16 am »
There's an old skiing proverb which I taught my daughter: if you aren't falling down ten times a day, you aren't trying hard enough. Then she broke her knee skiing, and couldn't become a solo pilot on her 16th birthday :(

D'oh! That's a drag. I assume she got her PPL as soon as her knee recovered, though.
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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31158 on: May 12, 2019, 12:05:47 am »
its not that I don't believe you,  but could you post pictures that would help to explain what the hell "taxidermy mice" are?



That reminds me; I must check the "Little Nipper" under my stairs. Not much use for taxidermy, though.

The gharial, and another medium-sized exhibit...
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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Offline bitseeker

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31159 on: May 12, 2019, 12:09:35 am »
Talk about, "something completely different." Today is quite the TEAngent. :-DD
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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31160 on: May 12, 2019, 12:11:09 am »
There's an old skiing proverb which I taught my daughter: if you aren't falling down ten times a day, you aren't trying hard enough. Then she broke her knee skiing, and couldn't become a solo pilot on her 16th birthday :(

D'oh! That's a drag. I assume she got her PPL as soon as her knee recovered, though.

Nothing as boring as a PPL :)

Go and play in close proximity with other aircraft in the sky, deliberately enter spins (with an instructor behind her) on the downwind leg, have instructors take you to ridiculous positions (e.g. directly over the end of the runway) and say "now get me home safely", and every landing was a forced landing.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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Online 0culus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31161 on: May 12, 2019, 12:11:27 am »
its not that I don't believe you,  but could you post pictures that would help to explain what the hell "taxidermy mice" are?



That reminds me; I must check the "Little Nipper" under my stairs. Not much use for taxidermy, though.

The gharial, and another medium-sized exhibit...

Man, if I woke up in the night to hit the head and ran across those in the dark...  :o
 

Offline bitseeker

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31162 on: May 12, 2019, 12:12:56 am »
Nothing as boring as a PPL :)

Go and play in close proximity with other aircraft in the sky, deliberately enter spins (with an instructor behind her) on the downwind leg, have instructors take you to ridiculous positions (e.g. directly over the end of the runway) and say "now get me home safely", and every landing was a forced landing.

Not boring, indeed! That's awesome.
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Online med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31163 on: May 12, 2019, 12:33:22 am »


The gharial, and another medium-sized exhibit...

You do realize (I hope) that the gharial has been in steep decline since the 1930's and is classified as "critically endangered" and I'll bet that head did not come from a dead individual. 
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Offline Kosmic

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31164 on: May 12, 2019, 12:46:47 am »
Kosmic (post #31124) -“Some weeks ago, I got another piece for my instrument collection from ESI. This time it's a SV-194B Voltage Calibrator.” ….”After some tests I realized the resistors had drifted though. Will need to find a solution for that.”

Are you sure the resistors have drifted? Here are the readings I get on my SV194 B without removing the resistors from the circuit. Some values are common, some aren’t but these resistors just don’t drift. The nine identical ones on the fuse side are all 40K and I have the ones across the bottom from right to left as 20K, 16K, 2K and 1.5922K The two up the other side are 1.038 ohms and 7.414 ohms. The four staggered ones from bottom to top are 200.13 ohms, 160.15 ohms, 20.172 ohms, and 20.172 ohms.

I mostly tested the ratio feeding 1kv. 10v was way off but it was getting better at 0.1V and 0.05V.

I will probably just try to clean it first (IPA) and then try to setup some compensation.
 

Online Mr. Scram

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31165 on: May 12, 2019, 12:47:36 am »
You do realize (I hope) that the gharial has been in steep decline since the 1930's and is classified as "critically endangered" and I'll bet that head did not come from a dead individual.

I'm pretty sure it's dead now.
 

Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31166 on: May 12, 2019, 12:57:37 am »
The interesting bits related to my leopard and gharial. Took one to be repaired on the way from back from picking up some equipment; found I probably ought to insure them.

:-// What are those?  :-//

Google is your friend, and they aren't test equipment, nor are they still alive.

My mother's house is famous amongst the ambulance staff that attend her occasionally. Some might regard it as creepy, but apparently taxidermy is becoming fashionable again :)
Google is NOT your friend if you are feeding it wrong. I was looking for anything except the animals.
Else I would not have asked as I am quite familiar with the extant species of the SUCHIA clade.

BTW, the only area where both words came up together and not related to animals was in armoured vehicles.
I was already envious of your MRAP until I thought of the parking situation here.
 
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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31167 on: May 12, 2019, 01:03:36 am »


The gharial, and another medium-sized exhibit...

You do realize (I hope) that the gharial has been in steep decline since the 1930's and is classified as "critically endangered" and I'll bet that head did not come from a dead individual.

I do indeed! From a photo, the taxidermist wondered if it was Victorian.

My leopard is from the mid 30s. My step-grandfather shot it in Assam because, according to family legend, it was a man-eater. The taxidermist spantaneously confirmed my belief that it is a large leopard, which supports the family legend.

The key date w.r.t. legality of selling them is apparently 1947.
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31168 on: May 12, 2019, 01:12:04 am »
That looks like those ancient exploding NiCd cells. I used to chuck them in a fire. That's what made them explode  :-DD

I do have to say that there's something nice about that little circuit. Looks neat and purposeful.
Yeah, aside from the self-detonating 1st gen MMLC capacitor, it actually is quite elegant in its simplicity; I love the beauty of form following function. It does have me thinking about just getting 4 AAA NiMHs and dropping them in there; would double its runtime and probably brighter longer due to lower IR of modern cells. Just that for 2-ish watts, you can get so much more out of LED & LiPo.[/b][/color]
Except it isn't. Looks very much like Siemens uncoated MKT (foil) capacitor.

I thought the MKT line were rolled foil/polyester? These are definitely stacked and have solder pads on the ends; pretty sure it's plastic-coated ceramic.

Meh. It's a 40-ish year-old capacitor; by definition it's as likely to explode as do it's job every time you plug the damn thing in.  :P

mnem
*charged*
The audio people love them. Whatever the reason. I prefer the encapsulated types.
 

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31169 on: May 12, 2019, 01:35:22 am »
Kosmic (post #31124) -“Some weeks ago, I got another piece for my instrument collection from ESI. This time it's a SV-194B Voltage Calibrator.” ….”After some tests I realized the resistors had drifted though. Will need to find a solution for that.”

Are you sure the resistors have drifted? Here are the readings I get on my SV194 B without removing the resistors from the circuit. Some values are common, some aren’t but these resistors just don’t drift. The nine identical ones on the fuse side are all 40K and I have the ones across the bottom from right to left as 20K, 16K, 2K and 1.5922K The two up the other side are 1.038 ohms and 7.414 ohms. The four staggered ones from bottom to top are 200.13 ohms, 160.15 ohms, 20.172 ohms, and 20.172 ohms.

I mostly tested the ratio feeding 1kv. 10v was way off but it was getting better at 0.1V and 0.05V.

I will probably just try to clean it first (IPA) and then try to setup some compensation.

Just a thought were you measuring those voltages with a 10MOhm meter or a GOhm one? If you do the numbers it matters and even nominal 10MOhm meters change their impedances at different ranges.

When I reset some of the resistors in my Cambridge Ratio box to improve it's accuracy (posted in here somewhere) I set up a spreadsheet to allow me to plug in the meter impedance to compensate what it was reading.
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Online beanflying

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31170 on: May 12, 2019, 01:48:22 am »
Not TEA related (but certainly related to funding more TEA and a bigger house to put it all in  :-DD ), but I walked with my MS in Computer Science today. Looking forward to working for a little while before possibly adding shit piled higher and deeper!  >:D

Congrats now get a job you long haired hippy sponge  ;D

Way back when I was fortunate to be among the last Australians to get free Tertiary education. In my third and forth years the then conservative tossers in charge changed that and started course charges with a post pre or post paid option paid back over time with increased Tax when earning over $X. Against that I was receiving a full government study assistance program which was enough for me to live on Campus and not starve.
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Offline Kosmic

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31171 on: May 12, 2019, 01:56:34 am »
Just a thought were you measuring those voltages with a 10MOhm meter or a GOhm one? If you do the numbers it matters and even nominal 10MOhm meters change their impedances at different ranges.

When I reset some of the resistors in my Cambridge Ratio box to improve it's accuracy (posted in here somewhere) I set up a spreadsheet to allow me to plug in the meter impedance to compensate what it was reading.

Tested with my Solartron 7061 (7.5 digits) in the ranges where the input impedance is supposed to be > 10GOhm.

Again that was just a quick check up but the error was so big i'm pretty sure some resistors drifted and the ratio was changed for some reasons.
 

Online beanflying

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31172 on: May 12, 2019, 02:18:24 am »
Just a thought were you measuring those voltages with a 10MOhm meter or a GOhm one? If you do the numbers it matters and even nominal 10MOhm meters change their impedances at different ranges.

When I reset some of the resistors in my Cambridge Ratio box to improve it's accuracy (posted in here somewhere) I set up a spreadsheet to allow me to plug in the meter impedance to compensate what it was reading.

Tested with my Solartron 7061 (7.5 digits) in the ranges where the input impedance is supposed to be > 10GOhm.

Again that was just a quick check up but the error was so big i'm pretty sure some resistors drifted and the ratio was changed for some reasons.

Quick check of the manual seems to indicate if goes to 10MOhm at 200 and 1kV which is similar to my Advantest 6871. The 34401A is a manual soft switch with a default of 10Mohm.
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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31173 on: May 12, 2019, 04:59:42 am »
its not that I don't believe you,  but could you post pictures that would help to explain what the hell "taxidermy mice" are?
Man, if I woke up in the night to hit the head and ran across those in the dark...  :o
You'd sit there 5 minutes waiting for the little fuckers to finish!!!  :-DD

More traditionally, for quite some time it was a "thing" to dress them up in formal dolls' clothing and pose them as carolers, in family scenes, or detailed breakfast & dinner settings. I personally find the whole thing pretty morbid and unnatural; let the poor fuckers die, IMO.

That looks like those ancient exploding NiCd cells. I used to chuck them in a fire. That's what made them explode  :-DD

I do have to say that there's something nice about that little circuit. Looks neat and purposeful.
Yeah, aside from the self-detonating 1st gen MMLC capacitor, it actually is quite elegant in its simplicity; I love the beauty of form following function. It does have me thinking about just getting 4 AAA NiMHs and dropping them in there; would double its runtime and probably brighter longer due to lower IR of modern cells. Just that for 2-ish watts, you can get so much more out of LED & LiPo.[/b][/color]
Except it isn't. Looks very much like Siemens uncoated MKT (foil) capacitor.

I thought the MKT line were rolled foil/polyester? These are definitely stacked and have solder pads on the ends; pretty sure it's plastic-coated ceramic.

Meh. It's a 40-ish year-old capacitor; by definition it's as likely to explode as do it's job every time you plug the damn thing in.  :P

mnem
*charged*
   The audio people love them. Whatever the reason. I prefer the encapsulated types.

   Those do sortof look the part... aside from the fact you can't see the stacking as obviously as with this one. These are what I typically associate with the type you're describing though. And looking at the PDFs you posted, it appears that the MKT product line includes both roll and stacked construction... I guess it is the fact it is made of metalized plastic film, whatever the construction? Any of these stacked ones have much more in common with a RIFA than any proper, trustworthy AL foil or ceramic cap IMO...

Not TEA related (but certainly related to funding more TEA and a bigger house to put it all in  :-DD ), but I walked with my MS in Computer Science today. Looking forward to working for a little while before possibly adding shit piled higher and deeper!  >:D
Congrats now get a job you long haired hippy sponge  ;D

Way back when I was fortunate to be among the last Australians to get free Tertiary education. In my third and forth years the then conservative tossers in charge changed that and started course charges with a post pre or post paid option paid back over time with increased Tax when earning over $X. Against that I was receiving a full government study assistance program which was enough for me to live on Campus and not starve.

Yeah, over here it's the newest branch of legalized loan sharking; very low interest rates but compounded daily, and if you take the lower payment rate options (which most can't afford not to, as the rate starts in the hundreds and then doubles or triples each year) then the loan "recapitalizes unpaid interest" every year. This then also gets compounded daily; such that I've been paying for nearly a decade, and still owe more than I ever received.  :palm:

mnem
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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #31174 on: May 12, 2019, 05:11:51 am »
...
   Keeping the TEA Bodge level at Bay  ;) 2mm Acrylic single pass 10mm/sec @ 70% power, could run a bit less or go faster but it works.

If only the 3DP was as fast as Laser  8)

Needs nickel-steel filister pan-head screws; or better yet, countersunk oval-head. Those zinc-plated philips washer-heads look horrible.  :P

mnem
Uh oh... SWMBO is asking for "help" with the laundry. I think I'll "delegate" to the oldest child.



 ;D I didn't have any pan heads for either side of the enclosure so I went Philips instead of Allen headed. Pan heads for the era of the contents would be much more appropriate ;)
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