Test Equipment Anonymous (TEA) group therapy thread

[tautech]

It doesn't trigger reliably at the moment, ...

Ha! Found it! 

It's staring right at ya !
D3 rising edge on an idle high bus. 

[RolandK]

I can't believe YHP used those pointer knobs to hold the push button lever mechanisms onto the switches, just seems wasteful. 


Must be an early one too, judging by the blue grey covers.

David

The manual from 1973 for up to 1212J-00590 has the knobs on side 6-20 last position listed:

04342-3261 KNOB:ROUND BLACK 1 ARROW 7 REQ'D

I did not find any change in section VII.

So i think the alu clamps at https://everist.org/NobLog/20130215_The_Q_meter.htm are not original. Perhaps someone harvested and upcycled the knobs.

With cheap i meant that they were a series part ready available - a 10 cent article - compared to the precission mechanical parts they disappear in the noise. The perspective 50 years later is completly different. As they tend to get brittle, they are nowadays expensive and hard to get.

[Andrew_Debbie]

Buy now, regret later 

Knipex

I don't regret my Knipex crimp tool.   Wish I had the ££££ to buy a full set of their tools.

[Robert763]

I can't believe YHP used those pointer knobs to hold the push button lever mechanisms onto the switches, just seems wasteful. 


Must be an early one too, judging by the blue grey covers.

David

The manual from 1973 for up to 1212J-00590 has the knobs on side 6-20 last position listed:

04342-3261 KNOB:ROUND BLACK 1 ARROW 7 REQ'D

I did not find any change in section VII.

So i think the alu clamps at https://everist.org/NobLog/20130215_The_Q_meter.htm are not original. Perhaps someone harvested and upcycled the knobs.

With cheap i meant that they were a series part ready available - a 10 cent article - compared to the precission mechanical parts they disappear in the noise. The perspective 50 years later is completly different. As they tend to get brittle, they are nowadays expensive and hard to get.

Only the designer knows for certain why they used knobs rather than collars. I can suggest a few possibilities:
1/ Slightly larger diameter stops the levers rattling. A custom collar is >>$$ than standard knob.
2/ Added mass to ensure correct operation of the latch spring in the switch. Things that work with human "feedback" can be troublesome when automated.
3/They were on hand when they built the prototype and just got carried through to production.

I think 2/ is a possibility

[Specmaster]

I'm going to throw this out there since I know many of you have encountered ham radio operators.  And in this case, an aspiring ham radio operator.

What's the deal with the scanners blaring constantly whenever you have to talk to one of these people?  I hate having to alternately have to shout over and hear through the noise of their scanners.  If you're talking to someone, turn it off or turn it well down.

Well, I'm not a ham but my scanner is going constantly.  But I do have the common sense and decency to switch it to mute when talking on the phone or if I have a visitor. And it's also on mute if I'm watching TV.

The only time it's switched off is when the Lady Cop is here. She has made it abundantly clear that the last thing she want's to hear when off duty is radio calls. I guess I can't blame her. 

 

It also begs the question, why is it on mute if you're watching TV, why not turn it off, I mean if anything remotely interesting is going to happen on the radio, you'll miss it anyway.

I take my scanner with me when I go to an active military airfield, so I can get to hear the pilots calling each other and also back to base when they have issues, like landing gear or munitions failure, and they have to return fully armed with the emergency services in attendance.

[Andrew_Debbie]

New Uni-T E .  No time to play now.    Back to work.

[med6753]

It also begs the question, why is it on mute if you're watching TV, why not turn it off, I mean if anything remotely interesting is going to happen on the radio, you'll miss it anyway.

Because switching it to mute involves one toggle switch vs multiple switches to turn it on/off.

Call me lazy I guess. 

[BU508A]

Not directly TE related, but to store tools, antenna cables, satellite finder, plugs, LNB, multiswitch etc.:
some DeWALT TSTAK stuff:

[Neper]

I'm going to throw this out there since I know many of you have encountered ham radio operators

There's even a few of us here.

What's the deal with the scanners blaring constantly whenever you have to talk to one of these people?

No idea. Bad upbringing, most probably. Just like people leaving the telly on when they have visitors or have it blaring in the background while they're on the phone.

Moot point here anyway, since all services which could be remotely interesting have gone digital and my old scanner won't decode them.

[Kosmic]

I got some more probes recently. Decided to test them like the other one.

Table of content:

(Including previous tests)

Part 1, Batch 1 Frequency response
Part 2, Batch 1 Fast pulse
Part 3, Batch 2 Frequency response
Part 4, Batch 2 Fast pulse
-->Part 5, Batch 3 Frequency response
Part 6, Batch 3 Fast pulse

The Setup:
I used a noise source to generate a signal from DC to 500MHz. The impedance of the source being 50Ohms, a 50Ohms Terminator was connected directly on the output of the noise source. The probe under test was connected to the termination with a bnc-to-probe adapter. The other end of the probe was connected to an Oscilloscope (Lecroy WavePro 960, 16GS/s, 2GHz bandwidth).



Agilent N2863A, 300MHz probe:


Frequency response of the N2863A (Green) from DC to 500MHz, 50MHz per division. Noise source in Cyan.


Lecroy PP005, 500MHz probe:
I must say I'm really impress with this one. I was expecting a lot worst, but the PP005 is a really good passive probe.



Frequency response of the PP005 (Green) from DC to 500MHz, 50MHz per division. Noise source in Cyan.


Tektronix P6046, 100MHz differential probe:
Please note, this is not really a fair comparison since I had to use the probe in a single ended configuration (not differential) Nevertheless, the impressive part is that this probe has a 100MHz bandwidth at 1X.



Frequency response of the P6046 (Green) from DC to 500MHz, 50MHz per division. Noise source in Cyan.


Tektronix P6202, 500MHz active probe:


Frequency response of the P6202 (Green) from DC to 500MHz, 50MHz per division. Noise source in Cyan.

[Cerebus]

It doesn't trigger reliably at the moment, ...

Ha! Found it! 

It's staring right at ya !
D3 rising edge on an idle high bus. 

Nope, that's the SPI !CS and is nothing to do with the problem, in fact the whole SPI setup is in another clock domain from the ADC core. No, it was the asynchronous trigger signal coming in via a synchroniser - it went through a synchroniser but the wrong kind of synchroniser, one that can lose input pulses shorter than a single clock. Now I'm trying to persuade Yosys to synthesise a 'type B' synchroniser for that signal and it doesn't want to. I might have to write a tiny test bench to find the precise right incantation to make a portable bit of synthesisable verilog rather than falling back to just invoking a technology specific FF cell.

[Kosmic]

And now the fast pulse for batch 3.

Table of content:

(Including previous tests)

Part 1, Batch 1 Frequency response
Part 2, Batch 1 Fast pulse
Part 3, Batch 2 Frequency response
Part 4, Batch 2 Fast pulse
Part 5, Batch 3 Frequency response
-->Part 6, Batch 3 Fast pulse

The Setup:
The probes are connected to my Lecroy oscilloscope calibration port via a probe-to-bnc adapter. The Calibration port is outputting a square pulse at 2MHz, 1V, <= 1ns rise time, 25 ns width. Impedance is 1MOhms.

*Every probes as been compensated before running the test.

Agilent N2863A, 300MHz probe:




Lecroy PP005, 500MHz probe:
Again, really good performance for a passive probe.




Tektronix P6046, 100MHz differential probe:




Tektronix P6202, 500MHz active probe:

[factory]

I can't believe YHP used those pointer knobs to hold the push button lever mechanisms onto the switches, just seems wasteful. 


Must be an early one too, judging by the blue grey covers.

David

The manual from 1973 for up to 1212J-00590 has the knobs on side 6-20 last position listed:

04342-3261 KNOB:ROUND BLACK 1 ARROW 7 REQ'D

I did not find any change in section VII.

So i think the alu clamps at https://everist.org/NobLog/20130215_The_Q_meter.htm are not original. Perhaps someone harvested and upcycled the knobs.

With cheap i meant that they were a series part ready available - a 10 cent article - compared to the precission mechanical parts they disappear in the noise. The perspective 50 years later is completly different. As they tend to get brittle, they are nowadays expensive and hard to get.

Only the designer knows for certain why they used knobs rather than collars. I can suggest a few possibilities:
1/ Slightly larger diameter stops the levers rattling. A custom collar is >>$$ than standard knob.
2/ Added mass to ensure correct operation of the latch spring in the switch. Things that work with human "feedback" can be troublesome when automated.
3/They were on hand when they built the prototype and just got carried through to production.

I think 2/ is a possibility

The part number starting with 04342 instead of 0370 suggests the knobs are a custom or modified part.

The later 4342A on the memory project website has the exactly the same metal clamps, suggesting they were changed at some point in production.
https://www.hpmemoryproject.org/pict/wall_b/anim/4342a_q90/viewer.htm

David

[factory]

Next up with is the little multifunction tester which I put through it’s paces with a random assortment of junk box parts from the retired Nortel engineer’s cookie tin of doom:

...snip...



I'm not surprised at the result here.  This was a junk box 7805 linear regulator.

...snip...

Anyhow, that's it for test equipment for today for me.  I'm about to head over to a friend's house for a little Christmas get together and need to stop to pick up a dessert on the way.  Tis the season.  As much as I enjoy the gatherings with friends, the longstanding hatred I have for the season lurks in the background regardless.

Are these even designed to test voltage regulators? Can't help thinking I've read they can't test them somewhere before too.

David

[Kosmic]

Next up with is the little multifunction tester which I put through it’s paces with a random assortment of junk box parts from the retired Nortel engineer’s cookie tin of doom:

...snip...



I'm not surprised at the result here.  This was a junk box 7805 linear regulator.

...snip...

Anyhow, that's it for test equipment for today for me.  I'm about to head over to a friend's house for a little Christmas get together and need to stop to pick up a dessert on the way.  Tis the season.  As much as I enjoy the gatherings with friends, the longstanding hatred I have for the season lurks in the background regardless.

Are these even designed to test voltage regulators? Can't help thinking I've read they can't test them somewhere before too.

David

No they are not.

[tggzzz]

Next up with is the little multifunction tester which I put through it’s paces with a random assortment of junk box parts from the retired Nortel engineer’s cookie tin of doom:

...snip...



I'm not surprised at the result here.  This was a junk box 7805 linear regulator.

...snip...

Anyhow, that's it for test equipment for today for me.  I'm about to head over to a friend's house for a little Christmas get together and need to stop to pick up a dessert on the way.  Tis the season.  As much as I enjoy the gatherings with friends, the longstanding hatred I have for the season lurks in the background regardless.

Are these even designed to test voltage regulators? Can't help thinking I've read they can't test them somewhere before too.

David

Highly unlikely.

Mine has a 9V battery, and is currently indicating the battery voltage of 6V is OK. I presume they have a 5V MCU inside, so couldn't apply more than that to the DUT

[RolandK]

The part number starting with 04342 instead of 0370 suggests the knobs are a custom or modified part.

The later 4342A on the memory project website has the exactly the same metal clamps, suggesting they were changed at some point in production.
https://www.hpmemoryproject.org/pict/wall_b/anim/4342a_q90/viewer.htm

David

After looking carefully there are other differences, too: A BNC connector in the HF line and different trim pots.

[med6753]

Well that is certainly much better.  Bum V724 (6AU6). The slightly excessive ripple observed will be resolved when I re-cap the entire scope. Going to install a plug-in and then let this guy cook for a while and see if it suffers from the same HV transformer issue as dirty dawg.

[Vince]

Tektronix P6046, 100MHz differential probe:

Frequency response of the P6046 (Green) from DC to 500MHz, 50MHz per division. Noise source in Cyan.

Just wondering.... what's up with all those spikes/glitches with that diff probe ? What could be causing them, what do they mean ?!   

[med6753]

Looking good so far but as it heats up it stinks like an old wood pile because of the remnants of the sawdust.

[WastelandTek]

Pulled the trigger on a brand new 344654A, should be here around new years hopefully, pretty excited.

Got it for the $16xx price, within hours of the purchase Newark revised the price up to $25xx.  I guess that is the inflation observed in real time, still, it made me feel better about a big ticket purchase I was having some anxiety about.

[Kosmic]

Tektronix P6046, 100MHz differential probe:

Frequency response of the P6046 (Green) from DC to 500MHz, 50MHz per division. Noise source in Cyan.

Just wondering.... what's up with all those spikes/glitches with that diff probe ? What could be causing them, what do they mean ?!   

I was wondering the same thing so I did some test with 50\$\Omega\$ load on the input ­of the scope.

They seem to be affected by the sampling rate so my guess is aliasing of high freq noise in the instrument.

500MS/s the peak is at 220MHz.


1GS/s now at 435MHz


16GS/s now completely disappeared.

[Zucca]

Pulled the trigger on a brand new 344654A, should be here around new years hopefully, pretty excited.

Got it for the $16xx price, within hours of the purchase Newark revised the price up to $25xx.  I guess that is the inflation observed in real time, still, it made me feel better about a big ticket purchase I was having some anxiety about.

You are a bastard (if you don't post a pic of the new puppy when it arrives)!
IMHO Newark prices are always so high for no reasons.

[med6753]

The verdict is in and it's not good. I have two Type 547's with potentially fatal HV transformer issues. After about 20 minutes the trace on dusty dawg slowly faded and disappeared. So apparently these two scopes were stored in a damp sawmill. 

What to do? There is an individual on the Facebook Old Tek group who is working on a computerized rewinding process for the HV transformer that shows promise but remains incomplete. In the meantime I am going to select one of the scopes and perform the SS conversation. This MIGHT lighten the load enough that even with some excessive leakage the the HV oscillator continues to run without overloading and shutting down. It's a crap shoot but worth a try. At this point have nothing to lose because as they stand right now they are both junk.         

[Andrew_Debbie]

Home from work.  The UT-622A is charging. Will post more when I get a chance.