Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 14560616 times)

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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88775 on: April 20, 2021, 07:20:40 pm »
Call that a reamer? This is a reamer...

Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88776 on: April 20, 2021, 07:30:25 pm »

I would guess that after having a rebore, you may need a catheter for a while until that internal wound heals.

Nope, according to what I was told the day after they release me the catheter comes out. I can't wait.  :-+

OK. I guess that means the reborer cauterises the wound, but what do I know. I had my prostate removed completely, which brings different problems.
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88777 on: April 20, 2021, 07:34:12 pm »
Call that a reamer? This is a reamer...



That might have worked on my arse a few weeks back.
 
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Offline mansaxel

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88778 on: April 20, 2021, 07:34:38 pm »

What has kept CDDA at the top has nothing to do with its value as a format, but rather the fact that greedy stupid people know it and know how to manage it for profit; nothing else.

mnem
 :popcorn:

Well, perhaps. One can also turn this about and say: The longer a given format exists, the better the investment in gear for that format becomes.

Also: Not until CD was 20 years old was the technology, pricing, and adaptation well advanced enough that lots of people could consider moving their most-listened tracks to file-based storage. And then to 128Kbit mp3, tops! Some years more and there was Vorbis and FLAC and other more encumbered formats.  Quality-wise up to the arrival of FLAC there simply was too much to lose in going compressed, unless some very careful design decisions were made.

The radio company where I worked between 2008 and 2016 had 48KHz 256Kbit MPEG2 as standard format for stereo tracks (24bit 48KHz linear stereo, ie 2.1Mbit, for recording music) all that period. This was feasible because encoding was made with some very clever hardware encoders that were capable of squeezing all possible quality from the MPEG system. This choice of course was related to the fact that the playout platform required a Hitachi FC SAN with SMB NAS heads to work properly, and then bytes are very expensive...

Therefore, unless someone had invented perpendicular recording drives earlier, digital music simply was not ready for the file transfer paradigm. That and the fact that it takes ages to download music using a modem!

I think that the storage angle on the problem is well explained by the fact that CD-R was a very popular format for file transfer.

You should read up on this Occam guy. Told you before, and the reasons keep stacking up...

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88779 on: April 20, 2021, 08:04:46 pm »
hp 437B meter repair..........


To affix the plate, I chose a type of glue I had in another room where I do a little modelling.
:-DD
Yeah right.....hardcore model train builds don't you mean ?  :o  :)

Oh you caught me!  :-DD

Ooh nice layout. Also don’t get me started on that again  :-DD

Oh hell yeh, thats another rabbit hole to fall into  :-DD
Who let Murphy in?

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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88780 on: April 20, 2021, 08:15:58 pm »
Did anyone go buy that Cologne treasure chest in the meantime?

The ad is gone, so I assume, that someone has bought it.
No, it wasn't me.  :)
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88781 on: April 20, 2021, 08:18:00 pm »

What has kept CDDA at the top has nothing to do with its value as a format, but rather the fact that greedy stupid people know it and know how to manage it for profit; nothing else.

mnem
 :popcorn:

Well, perhaps. One can also turn this about and say: The longer a given format exists, the better the investment in gear for that format becomes.

Also: Not until CD was 20 years old was the technology, pricing, and adaptation well advanced enough that lots of people could consider moving their most-listened tracks to file-based storage. And then to 128Kbit mp3, tops! Some years more and there was Vorbis and FLAC and other more encumbered formats.  Quality-wise up to the arrival of FLAC there simply was too much to lose in going compressed, unless some very careful design decisions were made.

The radio company where I worked between 2008 and 2016 had 48KHz 256Kbit MPEG2 as standard format for stereo tracks (24bit 48KHz linear stereo, ie 2.1Mbit, for recording music) all that period. This was feasible because encoding was made with some very clever hardware encoders that were capable of squeezing all possible quality from the MPEG system. This choice of course was related to the fact that the playout platform required a Hitachi FC SAN with SMB NAS heads to work properly, and then bytes are very expensive...

Therefore, unless someone had invented perpendicular recording drives earlier, digital music simply was not ready for the file transfer paradigm. That and the fact that it takes ages to download music using a modem!

I think that the storage angle on the problem is well explained by the fact that CD-R was a very popular format for file transfer.

You should read up on this Occam guy. Told you before, and the reasons keep stacking up...

Yeah I was at the peak of that transition to mp3. We actually had a fairly nice audio set up at Quasar back in 1997 based on mp3s. I remember ripping Plasticity from FLA then shooting the fuck out of 12 year olds for a couple of hours then helping macgyvering Q-ZAR guns on Saturdays. Was paid in games and shitty French beer on tap  :-DD.

Whole place was running on a pentium with windows 95 on it.



Sounds of the 90s for me:

https://sheneil.tripod.com/defact.wav

« Last Edit: April 20, 2021, 08:21:23 pm by bd139 »
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88782 on: April 20, 2021, 08:20:04 pm »
Call that a reamer? This is a reamer...


Now thats just being cruel  :-DD
Who let Murphy in?

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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88783 on: April 20, 2021, 08:22:48 pm »
I was just tryin' ta make da guy cringe a little... not pass out!!! :-DD

mnem
a'sides... 'dis idn't da foist tahm oi posted dat... >:D
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Offline Robert763

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88784 on: April 20, 2021, 08:45:41 pm »
Call that a reamer? This is a reamer...



No, it's a face milling cutter with replacable inserts.. :-DD

Resident Pedant.
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88785 on: April 20, 2021, 08:50:46 pm »
Anyway distractions aside from TE, a TE related post finally.

So I was going to work on a GPSDO so the plan was to do something fancy with microcontrollers as well but seeing as Cerebus thoroughly cornered the market with that one I thought I'd go back to basics and do something old school. Thus I have in my possession some 74hc4046's and 74hc390's and am going to build a good old fashioned PLL that will lock to a 1pps signal. I don't have anything that will kick out a 1pps signal at the moment so the plan is:

1. stuff the ref out on the 5384A into the back of the DG810 ref in so I have a consistent reference.
2. Get the DG810 to generate the 1pps signal.
3. Lock an independent OCXO module to it with a stack of 74hc390 dividers and the 4046 as the phase detector.
4. Observe the phase locking with a scope
5. Observe frequency difference with the 5384A
6. Try and develop a lock indicator for it.

Only horrible thing is the time constant for a 1pps loop filter is horrible so this is going to mean watching second long pulses shooting past each other like snails  >:( .

Assuming worst case it's possible that the phase lock could take a couple of days to happen if both clocks are fairly close but out of phase :-\

10KHz timing module would be nicer!!! Any suggestions?
 
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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88786 on: April 20, 2021, 08:53:51 pm »
Call that a reamer? This is a reamer...



No, it's a face milling cutter with replacable inserts.. :-DD

Resident Pedant.

Pedant isn't pedantic enough, it's a 3" shell mill. But a tool is what you use it for, so I have a 4lb square screwdriver, and that's gonna do some reaming out.  :)

(I thought what would look suitably terrifying and then typed "large shell mill" into image search.  >:D)

I was just tryin' ta make da guy cringe a little... not pass out!!! :-DD

mnem
a'sides... 'dis idn't da foist tahm oi posted dat... >:D

I was going for giving him a nice smooth finish - about 2 µm peak-to-peak.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Offline tautech

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88787 on: April 20, 2021, 09:02:18 pm »
Anyway distractions aside from TE, a TE related post finally.

So I was going to work on a GPSDO so the plan was to do something fancy with microcontrollers as well but seeing as Cerebus thoroughly cornered the market with that one I thought I'd go back to basics and do something old school. Thus I have in my possession some 74hc4046's and 74hc390's and am going to build a good old fashioned PLL that will lock to a 1pps signal. I don't have anything that will kick out a 1pps signal at the moment so the plan is:

1. stuff the ref out on the 5384A into the back of the DG810 ref in so I have a consistent reference.
2. Get the DG810 to generate the 1pps signal.
3. Lock an independent OCXO module to it with a stack of 74hc390 dividers and the 4046 as the phase detector.
4. Observe the phase locking with a scope
5. Observe frequency difference with the 5384A
6. Try and develop a lock indicator for it.

Only horrible thing is the time constant for a 1pps loop filter is horrible so this is going to mean watching second long pulses shooting past each other like snails  >:( .

Assuming worst case it's possible that the phase lock could take a couple of days to happen if both clocks are fairly close but out of phase :-\

10KHz timing module would be nicer!!! Any suggestions?
:-//
Are you really that much into butt hurt ?

With that cash surplus you mentioned just get one from Leo:
http://www.leobodnar.com/shop/index.php?main_page=index&cPath=107&zenid=3d9654045b724f60be983c26e6bb9d43
Avid Rabid Hobbyist
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88788 on: April 20, 2021, 09:07:25 pm »
What has kept CDDA at the top has nothing to do with its value as a format, but rather the fact that greedy stupid people know it and know how to manage it for profit; nothing else.
Well, perhaps. One can also turn this about and say: The longer a given format exists, the better the investment in gear for that format becomes.

Also: Not until CD was 20 years old was the technology, pricing, and adaptation well advanced enough that lots of people could consider moving their most-listened tracks to file-based storage. And then to 128Kbit mp3, tops! Some years more and there was Vorbis and FLAC and other more encumbered formats.  Quality-wise up to the arrival of FLAC there simply was too much to lose in going compressed, unless some very careful design decisions were made.

The radio company where I worked between 2008 and 2016 had 48KHz 256Kbit MPEG2 as standard format for stereo tracks (24bit 48KHz linear stereo, ie 2.1Mbit, for recording music) all that period. This was feasible because encoding was made with some very clever hardware encoders that were capable of squeezing all possible quality from the MPEG system. This choice of course was related to the fact that the playout platform required a Hitachi FC SAN with SMB NAS heads to work properly, and then bytes are very expensive...

Therefore, unless someone had invented perpendicular recording drives earlier, digital music simply was not ready for the file transfer paradigm. That and the fact that it takes ages to download music using a modem!

I think that the storage angle on the problem is well explained by the fact that CD-R was a very popular format for file transfer.

You should read up on this Occam guy. Told you before, and the reasons keep stacking up...

Yeah, there's a thing aboot Occam's Razor... the thing that everybody conveniently forgets... is the middle part: "The simplest solution that answers all the parts of a question is most likely the correct one."

By your own argument right here then, CDDA has outlived its tenure as an audio format with any objectively superior qualities by at least a factor of 2:1; honestly, more like 3:1, in the face of dozens of objectively superior formats and management schemes. The only thing that held it back was distribution, which was already in place at that time in the form of Digital Versatile Disc, which had more than enough storage for superior, even lossless audio formats, as well as all the metadata we take for granted right now, today.

Imagine what your 100-disk jukebox could have been like back in 2000 or so, even with the technology of the time: Everything we take for granted now with the iPud/iPad music playing experience... track info already included; cover art part of the filesystem... even room for extras like an exclusive music video. But no... because they decided against spending the time & money to process even the most basic metadata into the original CDDA specification, we still, to this day have to have online metadata services baked into every digital music management software product that might ever have to deal with CDDA. For that colossal, multi-generational waste of global resources alone every RIAA member executive should be hung up by their testicles until dead. :palm:

The single reason which answers all that, and the fact that it continues to persist even today, and still indirectly poisons all digital formats that have followed, is simple human greed.  :-//

mnem
 :popcorn:
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Online tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88789 on: April 20, 2021, 09:10:50 pm »
Anyway distractions aside from TE, a TE related post finally.

So I was going to work on a GPSDO so the plan was to do something fancy with microcontrollers as well but seeing as Cerebus thoroughly cornered the market with that one I thought I'd go back to basics and do something old school. Thus I have in my possession some 74hc4046's and 74hc390's and am going to build a good old fashioned PLL that will lock to a 1pps signal. I don't have anything that will kick out a 1pps signal at the moment so the plan is:

1. stuff the ref out on the 5384A into the back of the DG810 ref in so I have a consistent reference.
2. Get the DG810 to generate the 1pps signal.
3. Lock an independent OCXO module to it with a stack of 74hc390 dividers and the 4046 as the phase detector.
4. Observe the phase locking with a scope
5. Observe frequency difference with the 5384A
6. Try and develop a lock indicator for it.

Only horrible thing is the time constant for a 1pps loop filter is horrible so this is going to mean watching second long pulses shooting past each other like snails  >:( .

Assuming worst case it's possible that the phase lock could take a couple of days to happen if both clocks are fairly close but out of phase :-\

10KHz timing module would be nicer!!! Any suggestions?

Makes the 2 tests/day I could do on my 485 PSU look positively speedy!

Could you speed things up by manually observing the phase difference, and manually forcing it to start from a less suboptimal phase difference? Perhaps a shift register, and choose which tap to use for the synchronisation?

Could you test your scheme at 10kHz etc, and then simply change the clock frequency down to 1Hz?
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".
Having fun doing more, with less
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88790 on: April 20, 2021, 09:11:19 pm »
Anyway distractions aside from TE, a TE related post finally.

So I was going to work on a GPSDO so the plan was to do something fancy with microcontrollers as well but seeing as Cerebus thoroughly cornered the market with that one I thought I'd go back to basics and do something old school. Thus I have in my possession some 74hc4046's and 74hc390's and am going to build a good old fashioned PLL that will lock to a 1pps signal. I don't have anything that will kick out a 1pps signal at the moment so the plan is:

1. stuff the ref out on the 5384A into the back of the DG810 ref in so I have a consistent reference.
2. Get the DG810 to generate the 1pps signal.
3. Lock an independent OCXO module to it with a stack of 74hc390 dividers and the 4046 as the phase detector.
4. Observe the phase locking with a scope
5. Observe frequency difference with the 5384A
6. Try and develop a lock indicator for it.

Only horrible thing is the time constant for a 1pps loop filter is horrible so this is going to mean watching second long pulses shooting past each other like snails  >:( .

Assuming worst case it's possible that the phase lock could take a couple of days to happen if both clocks are fairly close but out of phase :-\

10KHz timing module would be nicer!!! Any suggestions?
:-//
Are you really that much into butt hurt ?

With that cash surplus you mentioned just get one from Leo:
http://www.leobodnar.com/shop/index.php?main_page=index&cPath=107&zenid=3d9654045b724f60be983c26e6bb9d43

This is a project not a purchase :)
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88791 on: April 20, 2021, 09:12:30 pm »
Call that a reamer? This is a reamer...   
No, it's a face milling cutter with replaceable inserts.. :-DD

Resident Pedant.
Pedant isn't pedantic enough, it's a 3" shell mill. But a tool is what you use it for, so I have a 4lb square screwdriver, and that's gonna do some reaming out.  :)   (I thought what would look suitably terrifying and then typed "large shell mill" into image search.  >:D)
I was just tryin' ta make da guy cringe a little... not pass out!!! :-DD

mnem
a'sides... 'dis idn't da foist tahm oi posted dat... >:D

I was going for giving him a nice smooth finish - about 2 µm peak-to-peak.

That "proud spot" you're trying ta smooth out...? It was an erection.  :palm:

mnem
 :clap:
« Last Edit: April 20, 2021, 09:14:28 pm by mnementh »
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Offline tonyalbus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88792 on: April 20, 2021, 09:13:49 pm »
Anyway distractions aside from TE, a TE related post finally.

So I was going to work on a GPSDO so the plan was to do something fancy with microcontrollers as well but seeing as Cerebus thoroughly cornered the market with that one I thought I'd go back to basics and do something old school. Thus I have in my possession some 74hc4046's and 74hc390's and am going to build a good old fashioned PLL that will lock to a 1pps signal. I don't have anything that will kick out a 1pps signal at the moment so the plan is:

1. stuff the ref out on the 5384A into the back of the DG810 ref in so I have a consistent reference.
2. Get the DG810 to generate the 1pps signal.
3. Lock an independent OCXO module to it with a stack of 74hc390 dividers and the 4046 as the phase detector.
4. Observe the phase locking with a scope
5. Observe frequency difference with the 5384A
6. Try and develop a lock indicator for it.

Only horrible thing is the time constant for a 1pps loop filter is horrible so this is going to mean watching second long pulses shooting past each other like snails  >:( .

Assuming worst case it's possible that the phase lock could take a couple of days to happen if both clocks are fairly close but out of phase :-\

10KHz timing module would be nicer!!! Any suggestions?
:-//
Are you really that much into butt hurt ?

With that cash surplus you mentioned just get one from Leo:
http://www.leobodnar.com/shop/index.php?main_page=index&cPath=107&zenid=3d9654045b724f60be983c26e6bb9d43

Or this one GPS+galileo : https://s.click.aliexpress.com/e/_AmKZwB
there is also 1 with displey, ik have that one: GPSDO: https://s.click.aliexpress.com/e/_9yt2l3
or a basic one..low price: https://s.click.aliexpress.com/e/_A4uFpl

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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88793 on: April 20, 2021, 09:21:08 pm »
I would like to take this moment to congratulate the TEAnonymous thread:

We have successfully managed to spend almost the entirety of the last two pages in some way or another obsessing over med's junk. Well done TEA!!!
  :clap:

mnem
Also, a special "Thank you!" to med for being such a good sport aboot it.  :-DD
« Last Edit: April 20, 2021, 09:24:27 pm by mnementh »
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Offline Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88794 on: April 20, 2021, 09:33:07 pm »
ok, I did pick up the THS720 - came with power supply, albeit not original, came with 2 150MHz Testec Probes, new battery, LCD fresh and crisp , even though it has one scratch that does not pose a real problem and checked out ok.

Also came with invoice which makes this tax deductable.

I realize it is not the over the top super duper gizmo and that there are better ones out there, but as a small general purpose portable gizmo for abroad this does not sound too bad an idea.

Still gotta take a couple of photos, but I was too tired today.
 
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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88795 on: April 20, 2021, 09:33:56 pm »
Anyway distractions aside from TE, a TE related post finally.

So I was going to work on a GPSDO so the plan was to do something fancy with microcontrollers as well but seeing as Cerebus thoroughly cornered the market with that one I thought I'd go back to basics and do something old school. Thus I have in my possession some 74hc4046's and 74hc390's and am going to build a good old fashioned PLL that will lock to a 1pps signal. I don't have anything that will kick out a 1pps signal at the moment so the plan is:

1. stuff the ref out on the 5384A into the back of the DG810 ref in so I have a consistent reference.
2. Get the DG810 to generate the 1pps signal.
3. Lock an independent OCXO module to it with a stack of 74hc390 dividers and the 4046 as the phase detector.
4. Observe the phase locking with a scope
5. Observe frequency difference with the 5384A
6. Try and develop a lock indicator for it.

Only horrible thing is the time constant for a 1pps loop filter is horrible so this is going to mean watching second long pulses shooting past each other like snails  >:( .

Assuming worst case it's possible that the phase lock could take a couple of days to happen if both clocks are fairly close but out of phase :-\

10KHz timing module would be nicer!!! Any suggestions?

Cheat - well play smart. Wait for a 1 PPS to go past and clear your divider counter (assuming clear == generate output pulse), then lock out the reset circuit. By the time the next 1 PPS comes by you'll only be ~1us at worst out of phase and it shouldn't take too long to get to lock.

Consider having two time constants for you loop - a relatively fast one for startup and a slower one for once you're closer to lock up.

If you're a real glutton for punishment I've got some Fasttrax GPS modules complete with board connectors and datasheets. You're welcome to one gratis if you want it.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Offline Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88796 on: April 20, 2021, 09:43:56 pm »
I would like to take this moment to congratulate the TEAnonymous thread:

We have successfully managed to spend almost the entirety of the last two pages in some way or another obsessing over med's junk. Well done TEA!!!
  :clap:

mnem
Also, a special "Thank you!" to med for being such a good sport aboot it.  :-DD

Hope he get's rid of this nuisance tho.
 
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Offline Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88797 on: April 20, 2021, 09:47:17 pm »
picked up another Canon EOS RP (with the EOS adapter) for 839 today.

This will quality my 50mm 1.2 for cash back (I got that with 1500 discount  :palm:) lowering the price by another 250.

Still a lot of money, but I am sure there will be someone very happy to be forwarded one of my cameras for little funds ...
 
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Offline xrunner

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88798 on: April 20, 2021, 09:50:03 pm »
Tests from the bench: hp 437B power meter with hp 8481A sensor

All the calibration factors of the sensor have been enterd into a table in the 437B, so an interpolated cal factor will be automatically used when the freq. is entered before measurement.

Item 1: Yaesu FT-70D HT

HT transmitting on 144.730 MHz, 30 dB atten. in-line, (30 dB offset entered into meter). HT setting was low power ~0.5 W (+27 dBm). Not expected to be spot-on as these HTs aren't set that accurately. Reading was 0.421 W.

More to follow as tests are performed ...
« Last Edit: April 20, 2021, 11:10:47 pm by xrunner »
I told my friends I could teach them to be funny, but they all just laughed at me.
 
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Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #88799 on: April 20, 2021, 10:07:44 pm »
I would like to take this moment to congratulate the TEAnonymous thread:

We have successfully managed to spend almost the entirety of the last two pages in some way or another obsessing over med's junk. Well done TEA!!!
  :clap:

mnem
Also, a special "Thank you!" to med for being such a good sport aboot it.  :-DD

Want a picture? I guarantee you'll be begging for the 80 year stripper instead.  :P :-DD

An old gray beard with an attitude.
 
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