开云体育

Ha! It is interesting that you mention the 465, I originally had my eye on that or the 475 when I decided on the 380. What sold me is the 380 was its advanced precise calculating features and FFT function. In fact I thought the FFT function was particularly interesting as I also had interest in spectrum analyzers so I felt I got the best of both worlds. My one regret with going with the 380 is update rate depending how I set the horizontal scale as it seems to be the case with many digital scopes (except maybe the really good digital scopes), that is when I realize how nice a analog scope is with its instantaneous update rate. Also depending on how I set my horizontal scale I can get aliasing and I am guessing that is another possible reason why the previous owner might have blown out both channels on one decade. Could not get readings on the screen so turned up the vertical scale but was deceived by aliasing, I was fooled by this as well, wondering why I wasn't getting the reading I was excepting until I adjusted the horizontal scale and and then there it suddenly appeared.

For all of you that are interested in the 7J20, Egge Siert just uploaded the entire US patent for
it. It
makes for interesting reading if you are interested in electro-optics, or in learning more about
this
unusual plugin.

Dennis Tillman W7PF

Indeed most interesting. Because the patent dropped off the perch in the early 90's the basic
principle is adopted by several manufacturers, chief of which is Ocean Optics who make them like
shelling peas. They use the same Czerny-Turner approach (Ocean's is actually a crossed Czerny Turner
for compactness), and up to date arrays from Hamamtsu. About $3k - $6k , powered from USB and
complete with spectral analysis software.

But in 1973, and typical for Tek, it was decades ahead of the curve.

Craig

For all of you that are interested in the 7J20, Egge Siert just uploaded the entire US patent for it. It makes for interesting reading if you are interested in electro-optics, or in learning more about this unusual plugin.

Dennis Tillman W7PF

File : /7J20 Patent #3886331.pdf
Uploaded by : calibrationfixture <eggeja2@...>
Description : Addition to 7J20 & J20 Photo Album


You can access this file at the URL:

calibrationfixture <eggeja2@...>

Thanks Steve! Now I feel vindicated for also buying the Anatek Blue ESR meter! It was a bit expensive but I like it and had fun putting the kit together. I didn't get as deep into it as changing the display, but as I mentioned earlier, adding the auto shutoff on/off switch next to the power switch has worked very well and I just used it last week fixing my wife's 22 year old Oster 4811 breadmachine that liked to shut off somewhere in the middle of kneading the dough (makes the wife quite unhappy when she comes home and finds the dough for her dinner rolls not done!) Ended up replacing all 4 electrolytic caps that were in it. Two on the power supply board and two on the logic board. Only one was over it's ESR but replaced all of them anyway. Put a new seal in the bottom of the bread pan while I was at it. Should last her another 22 years! She loves her breadmaker and I love my Blue ESR meter!

John

To: TekScopes@...
From: TekScopes@...
Date: Mon, 4 Apr 2016 14:24:40 -0700
Subject: [TekScopes] Re: ESR meters (again)


























Hi Dave,


I purchased two ESR meters a couple weeks ago, after doing a ridiculous amount of web-surfing/research.








The convention wisdom I found on the web was "if you are a hobbyist and need to do accurate L,C,R, and ESR, then the DE-5000 offers the best value for the price". However, I bought the AnaTek Blue / DaveParker ESR meter last week (in kit form),








Anatek Blue ESR Meter - Full Kit for Self Assembly











Anatek Blue ESR Meter - Full Kit for Self Assembly Blue ESR Meter Kit for capacitor equivalent series resistance (ESR) measurements.











View on anatekinstruments.com


Preview by Yahoo

















and just for giggles, I ordered an el-cheapo ESR meter from banggood.com (also in kit form).














DIY Multifunction Transistor Tester Kit For LCR ESR Transistor PWM Signal Generator M328











DIY Multifunction Transistor Tester Kit For LCR ESR Tra... This is Meter Tester DIY Kit for Capacitance ESR Inductance Resistor. Measurement Range: Resistor: 0.5� ~ 50M�. Capacitor: 30pF ~ 100mF. Indu...











View on www.banggood.com


Preview by Yahoo











But banggood sent me a DIY DDS function generator kit instead, so I'm in the process of getting that resolved.











The AnaTek Blue ESR works great and is reasonably accurate (I checked some 1% resistors with it).


I'll do some comparisons once I receive and assemble my banggood ESR meter.








Now, a little story about the AnaTek Blue ESR:








During the assembly, I swapped out the supplied leads with some really nice silicon wire. Next I attempted to "upgrade" its blue 3mm decimal point LEDs. The supplied LEDs are a noticeably dim relative to the brightness of the 7-segment display. I had some very bright 3mm blue LEDs in my parts bins, and being a smart guy, I knew I could swap out the dim LED for a bright one, and if it was too bright, I could tone it down just by putting an appropriate resistor in series with the new LED.








Well, it was not that easy... "Brightness-matching" went okay, but new LEDs had a problem. When displaying something like (.05) it looked beautiful ! But When displaying something (0.5) the 1st LED would not go completely dark, but only when the 2nd LED was being illuminated to its proper level. I ended up with this (.0.5) on the display. I spent the next few hours looking at the schematic, probing the drive voltages and timing with my oscilloscope, soldering resistors and even 1N4148 diodes in series with the my bright LEDs, and generally trying to debug why that darn LED would not go out completely. Long story short: I understand how the display driver circuit operates, and I think there is small error in the design. I ended up putting the original "magic blue LEDs" back in the meter and all is well.








Anyway, that's my 2 cents.


-Steve



































































































[Non-text portions of this message have been removed]

Hi Dave,
I purchased two ESR meters a couple weeks ago, after doing a ridiculous amount of web-surfing/research.


The convention wisdom I found on the web was "if you are a hobbyist and need to do accurate L,C,R, and ESR, then the DE-5000 offers the best value for the price". However, I bought the AnaTek Blue / DaveParker ESR meter last week (in kit form),


Anatek Blue ESR Meter - Full Kit for Self Assembly



Anatek Blue ESR Meter - Full Kit for Self Assembly Blue ESR Meter Kit for capacitor equivalent series resistance (ESR) measurements.



View on anatekinstruments.com
Preview by Yahoo





and just for giggles, I ordered an el-cheapo ESR meter from banggood.com (also in kit form).




DIY Multifunction Transistor Tester Kit For LCR ESR Transistor PWM Signal Generator M328



DIY Multifunction Transistor Tester Kit For LCR ESR Tra... This is Meter Tester DIY Kit for Capacitance ESR Inductance Resistor. Measurement Range: Resistor: 0.5惟 ~ 50M惟. Capacitor: 30pF ~ 100mF. Indu...



View on www.banggood.com
Preview by Yahoo



But banggood sent me a DIY DDS function generator kit instead, so I'm in the process of getting that resolved.



The AnaTek Blue ESR works great and is reasonably accurate (I checked some 1% resistors with it).
I'll do some comparisons once I receive and assemble my banggood ESR meter.


Now, a little story about the AnaTek Blue ESR:


During the assembly, I swapped out the supplied leads with some really nice silicon wire. Next I attempted to "upgrade" its blue 3mm decimal point LEDs. The supplied LEDs are a noticeably dim relative to the brightness of the 7-segment display. I had some very bright 3mm blue LEDs in my parts bins, and being a smart guy, I knew I could swap out the dim LED for a bright one, and if it was too bright, I could tone it down just by putting an appropriate resistor in series with the new LED.


Well, it was not that easy... "Brightness-matching" went okay, but new LEDs had a problem. When displaying something like (.05) it looked beautiful ! But When displaying something (0.5) the 1st LED would not go completely dark, but only when the 2nd LED was being illuminated to its proper level. I ended up with this (.0.5) on the display. I spent the next few hours looking at the schematic, probing the drive voltages and timing with my oscilloscope, soldering resistors and even 1N4148 diodes in series with the my bright LEDs, and generally trying to debug why that darn LED would not go out completely. Long story short: I understand how the display driver circuit operates, and I think there is small error in the design. I ended up putting the original "magic blue LEDs" back in the meter and all is well.


Anyway, that's my 2 cents.
-Steve

Feeding a 400 Hz sine wave from an FG 501 into channel one on my 2445B, I am able to measure voltage and frequency using the cursors and voltage using "MEASURE" but not frequency. Requesting frequency, I get CH1: SMALL OR LOW REP RATE SIGNAL.

Signal looks pretty good to me on the screen. What might be the problem?

John AI4TO

Hi John,

See the link below for a few pictures of the AFG5101 including one of its rear.




Succes with the repair,



Egge Siert

Hello,


This email message is a notification to let you know that
a file has been uploaded to the Files area of the TekScopes
group.


File : /7J20 Patent #3886331.pdf
Uploaded by : calibrationfixture <eggeja2@...>
Description : Addition to 7J20 & J20 Photo Album


You can access this file at the URL:



To learn more about file sharing for your group, please visit:



Regards,


calibrationfixture <eggeja2@...>

Hi all,

I consider myself lucky, because today my 2221 I bought on Ebay -as defective- arrived.
The really good news: it is not broken at all.
I assume the previous owner just not knew what buttons to press to see the traces, or get them triggered.
Being on X-Y did not help either, I think.

Now to the things that DO need some attention: The broken knobs.

To make it complete I need the following 4 items:


- One of the Vertical "cal" knobs is damaged. The size is about 10mm at the bottom, 9mm at the top and 12mm high. Shaft diameter is appr. 3.1mm, 0.125".

- The little "Select" button, this is the one that selects which cursor to adjust. I could not find a partnumber for this so far. Shaft diameter is appr. 2mm, 0.078".

- the "Time Base" knob is damaged, the transparent 'skirt' is still OK. The size is about 18.2mm at the bottom (not including the skirt), 16.9mm at the top and 22mm high. Shaft diameter is 1/4", so 6.2mm.

- And finally, the Pull to x10, and rotate to adjust the calibration knob is missing. I believe the partnumber for this is 366-0641-00. The shaft diameter is 3.1mm, 0.125" too.

So far I found the first one on Ebay and with Qservice, but no luck for the other 3...

I hope somebody here can put me on the right track to obtain these missing items??

I try to include some pictures here:






Un saludo,

Leo

So, does anyone know the connector pinout on the P620x series? I
believe it's a Hirose HR10 series but what are the pins?

On Mon, 4 Apr 2016 at 11:49 david.wilson92@... [TekScopes] <
TekScopes@...> wrote:

I have an update for the TDS 380

I almost removed one of the hybrids but never could get the last few so I
decided I would resolder all the joints and put this scope back together to
play around with. This is my first scope by the way and I couldn't resist
the curiosity of using this instrument. Also I want to thank all the great
people who helped me along the way in troubleshooting this scope, if
anything I learned a few things about troubleshooting scopes and about
buying used scopes off ebay. If I decide to buy once again I will try to be
a little more careful so that I don't get sucker scoped!

Hey David,

thanks for the update, and have fun with your 380.
Personally I'd never buy a scope in full working order, as that'd deprive
me of the opportunity to fix it and learn something new. My kids tease me
about this; "Dad, now that the scope's working, what good is it to you?",
or looking at eBay "Dad, that one is listed as good - that's no use to
you", and so on.
Now the TDS380 isn't an ideal beginner's fixer-upper, as you've found, so
maybe next go for one that is fully documented and less integrated. Like
perhaps a 465 or a 2400-series - as clearly you need at least one more
scope ;).

Siggi

I bought a 7854, two in fact in the past week, mostly because they are high on the want list for my collection, and they came up cheap on eBay. Going to be interesting, both claim to work, but only one was willing to provide images showing the self test completion. The 7854+TDR combo looks really nice on paper, will need to check it out in real life... And learn to use a 7854!
Nathan KK4REY

Sent using CloudMagic Email []
On Mon, Apr 4, 2016 at 19:09, Craig Sawyers' c.sawyers@... [TekScopes] <TekScopes@...> wrote:

I assume that a failure would be "digital", either it works or it doesn't? I may have my hopes up a
little
bit high on this one... Tested working S-6 heads seem to go for more than I paid for the 7854 with
all
this installed..
Nathan KK4REY

Don't unnecessarily get concerned - it might work just fine and dandy. Mine does, in fact I was using
it today to see precisely how lousy BNC connectors can be.

I assume that a failure would be "digital", either it works or it doesn't? I may have my hopes up a
little
bit high on this one... Tested working S-6 heads seem to go for more than I paid for the 7854 with
all
this installed..
Nathan KK4REY

Don't unnecessarily get concerned - it might work just fine and dandy. Mine does, in fact I was using
it today to see precisely how lousy BNC connectors can be.

I assume that a failure would be "digital", either it works or it doesn't? I may have my hopes up a little bit high on this one... Tested working S-6 heads seem to go for more than I paid for the 7854 with all this installed..
Nathan KK4REY

Sent using CloudMagic Email []
On Mon, Apr 4, 2016 at 18:58, Craig Sawyers' c.sawyers@... [TekScopes] <TekScopes@...> wrote:

So it may be a real
miracle if it arrives intact. I take it that the sampler is made out of tiny quantities of
unobtainium, no
chance for repair if it is screwed up?

Mine arrived without too - and survived because the guy at least bagged it in antistatic wrap. And
yes - not a chance of repair - the business end is an alumina thick film hybrid with 6 chip diodes
bonded onto it. It is unlike any conventional sampling bridge - the S4 and S6 work by a fast
travelling wave trapping charge on diodes as it propagates. The 1GHz S1, possibly S2 and definitely
S3 (because I fixed mine when it was DOA) are repairable because fast Agilent surface mount diodes can
be pressed into use. But the S4 and S6 are simply not possible.

So it may be a real
miracle if it arrives intact. I take it that the sampler is made out of tiny quantities of
unobtainium, no
chance for repair if it is screwed up?

Mine arrived without too - and survived because the guy at least bagged it in antistatic wrap. And
yes - not a chance of repair - the business end is an alumina thick film hybrid with 6 chip diodes
bonded onto it. It is unlike any conventional sampling bridge - the S4 and S6 work by a fast
travelling wave trapping charge on diodes as it propagates. The 1GHz S1, possibly S2 and definitely
S3 (because I fixed mine when it was DOA) are repairable because fast Agilent surface mount diodes can
be pressed into use. But the S4 and S6 are simply not possible.

I have an update for the TDS 380

I almost removed one of the hybrids but never could get the last few so I decided I would resolder all the joints and put this scope back together to play around with. This is my first scope by the way and I couldn't resist the curiosity of using this instrument. Also I want to thank all the great people who helped me along the way in troubleshooting this scope, if anything I learned a few things about troubleshooting scopes and about buying used scopes off ebay. If I decide to buy once again I will try to be a little more careful so that I don't get sucker scoped!

I see it now - under CAL07 (R2918 and/or R2931).

Thanks!
Barry - N4BUQ

I am well aware of that, I do have a bag of terminations on the way as well. Unfortunately the eBay seller does not know this, and it looks like it will be in transit without termination... So it may be a real miracle if it arrives intact. I take it that the sampler is made out of tiny quantities of unobtainium, no chance for repair if it is screwed up?
Nathan KK4REY

Sent using CloudMagic Email []
On Mon, Apr 4, 2016 at 18:42, Craig Sawyers' c.sawyers@... [TekScopes] <TekScopes@...> wrote:

As I understand this, the interconnect cable being of a certain electrical length was to delay the

pulse

reaching the S-6 until after the trigger? So that would be satisfied by anything that delayed at

LEAST

750ps?

No - it is just a practical length of semi-rigid to go from the S52 to the S6. You have to use high
quality semi rigid though - you are trying to get low aberration 25ps rise time through it so
attenuation and return loss are important. This sort of thing
from Minicircuits probably the 5" version at $10

The "Test Line" is specced at 1ns, and I assume that this was to make the interconnection from

I think that is just part of the familiarisation - stick an unterminated line on the S6 and watch
the reflection come back.

What you definitely need to do is treat the S6 with utmost respect. They are static sensitive - in
fact Tek did an apps note 42W-5850 "Preventing Sampling Head Damage", and you can destroy an S6 with
static discharge from your finger, or a charged up bit of coax. I keep the inputs of the travelling
wave heads (S4 and S6) with a 50 ohm terminator on the inputs when not in use. I bought a bag of
cheap ones for precisely that. The other thing is to discharge any coax you connect to the input -
just short out ground to centre pin for a second before connecting to your S6.





[Non-text portions of this message have been removed]

As I understand this, the interconnect cable being of a certain electrical length was to delay the

pulse

reaching the S-6 until after the trigger? So that would be satisfied by anything that delayed at

LEAST

750ps?

No - it is just a practical length of semi-rigid to go from the S52 to the S6. You have to use high
quality semi rigid though - you are trying to get low aberration 25ps rise time through it so
attenuation and return loss are important. This sort of thing
from Minicircuits probably the 5" version at $10

The "Test Line" is specced at 1ns, and I assume that this was to make the interconnection from

I think that is just part of the familiarisation - stick an unterminated line on the S6 and watch
the reflection come back.

What you definitely need to do is treat the S6 with utmost respect. They are static sensitive - in
fact Tek did an apps note 42W-5850 "Preventing Sampling Head Damage", and you can destroy an S6 with
static discharge from your finger, or a charged up bit of coax. I keep the inputs of the travelling
wave heads (S4 and S6) with a 50 ohm terminator on the inputs when not in use. I bought a bag of
cheap ones for precisely that. The other thing is to discharge any coax you connect to the input -
just short out ground to centre pin for a second before connecting to your S6.

The readout text is adjusted on the A5 controller board for the 2465B scope. There are two pots, one for the size and one for position. They will not affect the calibration.