Re: Anyone Have a Peltola Socket?
I see where parts of that site are copied to the TekWiki page. Perhaps it would be good to add a statement to that page stating that those can still be purchased and a link to their webpage for it? Just a thought.
Thanks,
Barry - N4BUQ
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----- Original Message ----- From: "n4buq" <n4buq@...>
To: "tekscopes" <[email protected]>
Sent: Friday, February 18, 2022 9:19:48 PM
Subject: Re: [TekScopes] Anyone Have a Peltola Socket? Wow. I had no idea those would still be available!
Thanks,
Barry - N4BUQ
----- Original Message -----
From: "David C. Partridge" <david.partridge@...>
To: "tekscopes" <[email protected]>
Sent: Friday, February 18, 2022 8:49:43 PM
Subject: Re: [TekScopes] Anyone Have a Peltola Socket? Tek still sell them
<>
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of n4buq
Sent: 19 February 2022 01:01
To: tekscopes <[email protected]>
Subject: [TekScopes] Anyone Have a Peltola Socket?
Just wondering if anyone knows where I might get one of the Peltola sockets. I
would like to replace one in one of the boards in my 7704A.
Thanks,
Barry - N4BUQ
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Are you suggesting that the 130's readings are affected by a DUT's loss? One of this instrument's virtues is that its measurement technique is relatively insensitive to both shunt and series loss of the DUT, unlike the RC relaxation oscillator-based capacitor testers commonly found in low-cost form.
--Cheers
Tom
--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford University
Stanford, CA 94305-4070
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On 2/19/2022 11:33, Dave Wise wrote: I wasted some time on this. Adjusting for C is wrong; what really matters is the RC time constant. Since R is typically 1% tolerance, the ideal C may be 1% off too.
This may not be enough to matter in most cases, but if you¡¯re dealing with differential inputs, it¡¯s critical for achieving good common mode rejection.
Dave Wise
From: [email protected] <[email protected]> On Behalf Of Albert Otten via groups.io
Sent: Saturday, February 19, 2022 3:59 AM
To: [email protected]
Subject: Re: [TekScopes] Type 130 L-C Meter
On Sat, Feb 19, 2022 at 05:25 AM, Ed Breya wrote:
One thing I've never seen in any related documents, is any mention of a very
important possible use - to measure and adjust the input C of a scope This possible use is mentioned in some input normalizer documents, f.i. 067-0538-00 (Tekwiki). Some old messages , f.i. #116119, addressed this.
Albert
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I wasted some time on this. Adjusting for C is wrong; what really matters is the RC time constant. Since R is typically 1% tolerance, the ideal C may be 1% off too. This may not be enough to matter in most cases, but if you¡¯re dealing with differential inputs, it¡¯s critical for achieving good common mode rejection. Dave Wise From: [email protected] < [email protected]> On Behalf Of Albert Otten via groups.io Sent: Saturday, February 19, 2022 3:59 AM To: [email protected]Subject: Re: [TekScopes] Type 130 L-C Meter On Sat, Feb 19, 2022 at 05:25 AM, Ed Breya wrote: One thing I've never seen in any related documents, is any mention of a very
important possible use - to measure and adjust the input C of a scope This possible use is mentioned in some input normalizer documents, f.i. 067-0538-00 (Tekwiki). Some old messages , f.i. #116119, addressed this. Albert
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Re: Tek 2211 - need a real manual (blue cover?)
On Saturday 19 February 2022 04:58:26 am David Templeton wrote: Why do would need a paper copy over electronic? I have a "bench computer", but it's down, and no particular time frame for bringing it back up again. Then there's foldout schematics... I wouldn't mind having a paper manual for my 2246, if somebody has one they'd be willing to part with. -- Member of the toughest, meanest, deadliest, most unrelenting -- and ablest -- form of life in this section of space, ?a critter that can be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" - Information is more dangerous than cannon to a society ruled by lies. --James M Dakin
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Re: Tek 2715 75 to 50 ohms conversion
2714 and 2715 both have F connector inputs for CATV.
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Re: 2465 Delta Cursor not visible
Hey Nigel,
The cursors are generated by the readout board. The X/Y location of
horizontal/vertical cursors comes from the A5 board via the DLY_REF_0 and
DLY_REF_1 signals, but the dots are drawn by the "character generation"
circuitry. The discussion of how this is done in the "Theory of Operation"
section is quite good, although the machinery is pretty intricate.
In your shoes I'd look at the DLY_REF_0/1 lines to begin with, perhaps the
level of the missing cursor line is off-scale.
Siggi
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On Sat, Feb 19, 2022 at 7:24 AM NigelP <nigel-pritchard@...> wrote: Further examination and direct comparison with a second working 2465 have
highlighted the fact that the Readout Intensity control, while doing what
it should in principle, doesn't actually extinguish the readout display
when set to mid-position as it should. Not sure whether this is any part of
the problem or not but I can't see anywhere that you can preset the level
of intensity at this position.
Also I can't locate any explanation of exactly how the cursors are
generated, or whereabouts in the circuitry. Are they created in the Display
Sequencer U650 or in the A4 Readout board somewhere?
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Re: Tek 2211 - need a real manual (blue cover?)
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On Feb 19, 2022, at 1:57 AM, David Templeton <vexorg.calibra@...> wrote:
?There¡¯s pdf on tekwiki
David
On 19 Feb 2022, at 09:26, battyhugh <Hugh@...> wrote:
?I just acquired a 2211 - which seems to be in good working order. Does anyone have an original manual for it?
Thanks
Hugh
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Re: USB interface for the DPO / P7001
A little update to my project I've added some pictures of the current progress: /g/TekScopes/album?id=270172Since the Teensy is so powerful, I decided to add controller functionality to it. So beside providing a USB interface, the new board can simulate a connected computer. One of the first programs which were released for the DPO was "pulse parameter analysis". It's explained in the operator's manual of the scope. I'm currently in the progress to port this program onto the Teensy. Holger
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Re: 2465 Delta Cursor not visible
Further examination and direct comparison with a second working 2465 have highlighted the fact that the Readout Intensity control, while doing what it should in principle, doesn't actually extinguish the readout display when set to mid-position as it should. Not sure whether this is any part of the problem or not but I can't see anywhere that you can preset the level of intensity at this position.
Also I can't locate any explanation of exactly how the cursors are generated, or whereabouts in the circuitry. Are they created in the Display Sequencer U650 or in the A4 Readout board somewhere?
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On Sat, Feb 19, 2022 at 05:25 AM, Ed Breya wrote: One thing I've never seen in any related documents, is any mention of a very
important possible use - to measure and adjust the input C of a scope This possible use is mentioned in some input normalizer documents, f.i. 067-0538-00 (Tekwiki). Some old messages , f.i. #116119, addressed this. Albert
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Tek 2211 - need a real manual (blue cover?)
I just acquired a 2211 - which seems to be in good working order. Does anyone have an original manual for it?
Thanks
Hugh
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Re: Tek 2715 75 to 50 ohms conversion
Jaap and Alfredo:
Understand re loss of min pand,
Is the connector on the 2715 the 50 or 75 Ohm variation of they type N (or BNC?)
Beware the different inner conductor diameter of 75 vs 50 Ohm connectors,
Jon
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I too have a Type 130, picked up at a flea market many years ago. Not only was it a good deal (I recall about USD15), but it worked right off the bat, and very well. Over the years, I've replaced some questionable components like Al caps. It still has its original tubes, and even the paper caps. I've gathered a set of modern plastic caps for when the time comes, and a round or two of spare tubes, but not needed so far.
I have very few old pieces of gear anymore that use vacuum tubes, but this one's a keeper. It's just ... nice. What else can you say?
Once you get it working again, you'll see how nice it is, for various uses within its rather limited measuring range. One thing I've never seen in any related documents, is any mention of a very important possible use - to measure and adjust the input C of a scope. I'd guess that in-house, these were used extensively for tweaking up scopes during manufacture, not just measuring components.
I recall a number of discussions here over the years about scope input C assessment, and tweaking it using "input normalizers" and such. With a 130, you can just measure it directly and tweak it to spec.
If you plan to use it with various remote accessories, I'd recommend using 75 ohm (or even higher if you have it) coax. This gives a little less C/foot, allowing for a little longer cable to reach the DUT, while being able to null it out up to the 75 pF or so limit. Three feet of 50 R coax is marginal, but in 75 R it should be OK. So, let's say you want to check a scope's input C. Put a 3' (or less) 75 R BNC (with a PL-259 to BNC adapter, for example) line on the 130, and null it zero, with the far end unhooked. Then you plug it into the scope, and there's the input C. The 1 meg R part only has a small effect on the C reading.
Good luck in getting this old beauty running right again.
Ed
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Re: Anyone Have a Peltola Socket?
Wow. I had no idea those would still be available!
Thanks,
Barry - N4BUQ
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----- Original Message ----- From: "David C. Partridge" <david.partridge@...>
To: "tekscopes" <[email protected]>
Sent: Friday, February 18, 2022 8:49:43 PM
Subject: Re: [TekScopes] Anyone Have a Peltola Socket? Tek still sell them
<>
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of n4buq
Sent: 19 February 2022 01:01
To: tekscopes <[email protected]>
Subject: [TekScopes] Anyone Have a Peltola Socket?
Just wondering if anyone knows where I might get one of the Peltola sockets. I
would like to replace one in one of the boards in my 7704A.
Thanks,
Barry - N4BUQ
|
Re: Anyone Have a Peltola Socket?
Tek still sell them <>
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-----Original Message----- From: [email protected] < [email protected]> On Behalf Of n4buq Sent: 19 February 2022 01:01 To: tekscopes < [email protected]> Subject: [TekScopes] Anyone Have a Peltola Socket? Just wondering if anyone knows where I might get one of the Peltola sockets. I would like to replace one in one of the boards in my 7704A. Thanks, Barry - N4BUQ
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Well, I downloaded the Vintage Workbench article on the 130 by Alan Hampel from VintageTek. Outstanding piece and written so well. Guy has a knack for making a technical subject fascinating and absorbing. All too much technical articles are dry as dust. The upgraded schematic is perfect for signal tracing the unit, and the smaller side notes and pieces are full of interesting history and tidbits.
Damn color printer crapped out, so I had to print the first installment on the laser. Will put all three segments on a thumb drive and take it down to OrificeMax and print out a color copy and bind it in a report cover for future use.
Thanks Gents.
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On 2/17/22 22:05, Mark Vincent wrote: Jerome,
The 10meg resistors I got from Mouser are 1/2W Xicon 273 series. You may want to get extras in this value for other items. The 1% types have a low temperature coefficient which is better in low level circuits. The 5W I mentioned I got from ebay from China. You can get the 1% types now which I prefer. If you want to add inrush limiting, add a 527-CL70 NTC from the mains to the power transformer. The dual 15mfd in the B+ supply can be a single 33mfd ULD type. R403 can be increased in resistance, e.g. 3300 or 3500 ohms. This reduces the current through the VR tube and keeps the lower B+ stable.
I got my 130LC last year after looking for some time. I am glad I got mine and restored it. It is great to use when needed. I am sure you will be happy with yours when you get it going. I am glad to see one of these being brought back to life and used.
Mark
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Anyone Have a Peltola Socket?
Just wondering if anyone knows where I might get one of the Peltola sockets. I would like to replace one in one of the boards in my 7704A.
Thanks,
Barry - N4BUQ
|
Re: Tek TDS-3000 V3.41 Firmware
Success!
Thanks to all that provided help. Your comments and link caused me to look carefully at the Tek files and to reread the included instructions. Upon rereading, I realized I had been copying the inner folders to the disks, instead of only their contents as the instructions cautioned. I was unsure about copying the version.dat files, but did so anyway. The resulting disks loaded V3.41 successfully. It was a relief to find the computer's 3-1/2-inch drive working properly after all of these years.
Bruce, KG6OJI
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On Tue, Feb 15, 2022 at 07:27 PM, Mark Vincent wrote:
"Renee and Tom, let us know how you are coming on your restoration since you to mentioned it. I hope you two get them going to your satisfaction. I hope this list helps you two and anyone else that chooses to use it."
Hi Mark,
I just finished troubleshooting the significant problems in my 1982 465B. Now that I have verified that all the functions basically work I will compile list of parts needed to replace the electrolytic caps and other dodgy parts. The list you posted will be very helpful and is much appreciated.
Cheers,
Tom
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Re: Troubleshooting 465Bs With Dead Channel 2
Thank you David Templeton, Harvey White and Mark Vincent for responding to my 465B troubleshooting request. During my subsequent troubleshooting I found that, with the AC-GND-DC Switch set to DC, the gate of the channel 2 input FET was sitting at ~0.5Vdc. Per the service manual that point should be at 0V under those conditions. All the associated components of the input circuitry checked out good so I swapped the dual FETs, Tek P/N 151-1090-00, between channels 1 and 2. That resulted in all the malfunction symptoms (Dead channel and vertical position interaction) also swapping channels.
I now have a replacement 151-1090-00 on order from Qservice Electronics.
Cheers,
Tom
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Glydeck
Jean-Paul
David C. Partridge
ebrucehunter
Tom Phillips