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Re: Tektronix jewelry
¿ªÔÆÌåÓýI calculated 6 dollars worth of gold...and that's
if the chain is gold filled too. If not...about $1.
?
Les
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Re: Could please any one give a clue about this nice pulsed line generator??
Ed you say"I found that the outer foil has a longitudinal gap so that it
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doesn't totally enclose the conductors, so it may behave strangely as a single line - it's really optimized for differential use." In my experience with "slow wave helical line/Tesla coil"? better if? shield "only" carry longitudinal current and capacitive current , the longitudinal gap avoid Peripheral current circulation, like a turn shorted...mean more "Q". The dielectric is less important, since inside the coil the electric field is minimal, opposed to the electric field between coil and shield. This is the reason why you need more wire to obtain electrical length, compared with straight wire in air like antenna.. In straigh wire , all his length point have electrical field to ground or shield (coax cable) which in turn determine the capacity for unit of lenght , a coiled transmission line, or slow wave helical..only "see/feel" near the half of the electric field which is similar to? be immersed in a medium with less permittivity...since the inner surface of the coil has less electrical gradient between turn, then you need more wire to achieve the desired electrical lenght.. Using helical line/delay line is convenient since the total length could be shorted, but until now, I m not clear about how calculate for 50 Ohms. You say"For the actual scope measurements, you should have some good coaxial attenuators, or a step attenuator, to knock the level down some. The average pulser power is no problem, but the peak voltage may cause all sorts of strange effects by turning on protection devices and ringing the front-end parasitics. " Fortunately my unit come with a very nice step attenuator 25V to 250mV..!!plus a variable control +-5%. > Gabriel. --- In TekScopes@..., "Ed Breya" wrote: > > The simplest and most likely to work way to extend the line is just using more .141 semi-rigid line. If you have any RG-8 cables - the big stuff - and an adapter for N to SMA, it should definitely work better than RG-58 since it will have much lower loss, and maybe comparable to .141. > > There is a slightly more compact possible alternative, but I don't know yet. For one of my pulser designs, I had planned to try a section of scope vertical delay line in differential mode, with the avalanche operation between the oppositely charged lines, then transformer-coupled into a nonlinear transmission line edge compressor. I have the line mounted mechanically in a plug-in only, but not yet rigged for any experiments. > > The 7000 series appear to all (I don't know about the 7104) use the same stuff, which looks like it's made with bare copper conductors and outer foil, with HDPE dielectric. It's supposedly about 100 ohms differential, but may act as about 50 ohms common-mode with the conductors tied, or maybe with one conductor grounded to the foil. I found that the outer foil has a longitudinal gap so that it doesn't totally enclose the conductors, so it may behave strangely as a single line - it's really optimized for differential use. > > If you happen to have any pieces of delay line or 7000 carcasses available, you may want to experiment with it. I'm curious about how it would act with different wiring arrangements, what the true impedance is, and whether it's low enough in loss for pulser applications. It's heavier than the .141 cable, but on the other hand, it doesn't have silver plated conductors, and the HDPE isn't as good as PTFE. Maybe it's comparable then - the larger size offsetting the lossier materials. Or maybe not. > > It's also possible to extend the pulse width arbitrarily by terminating and feeding the charge line at the distal end with a 50 ohm source (at the charge voltage!), but it is much more complicated than the normal method. The power dissipation can quickly get out of hand, and the commutation must be provided by additional circuitry, since there's no reflection from the line. > > For the immediate purpose, I'd recommend just using more cable. > > For the actual scope measurements, you should have some good coaxial attenuators, or a step attenuator, to knock the level down some. The average pulser power is no problem, but the peak voltage may cause all sorts of strange effects by turning on protection devices and ringing the front-end parasitics. > > Ed > > --- In TekScopes@..., "iglesia_cristiana_arpas_eternas" iglesia_cristiana_arpas_eternas@ wrote: > > > > Today the Pulse Gen come to live, after replace the weak Q100 transistor by selected from what ever transistor I have in my shop..the winner was a npn switching "MPSH10". > > The rise time seems to be right on my unfinished to cal high frequency response 2465B scope..paradoxical..I brought this Gen in order to Cal my scopes ..now I haven`t a calibrated scope in this high impulse picosecond domain..to test this Gen..a dog chasing his tail!!! > > The only I can do is an act of "believe" in avalanche physic & Tek circuit implementation. > > > > As you people warning early, make an extension transmission line from common RG58...work but the pulse is not flat, the decay near linearly along his width..about 80ns. > > Any suggestion about how to make/obtain 15 feet of very good coax cable??? . > > Also please could any one post a pic on what is expected to see on a 2465B once connected to this Gen, about rise time and flatness?. > > > > --- In TekScopes@..., "iglesia_cristiana_arpas_eternas" wrote: > > > > > > The Generator arrive today from USA to my Argentine door!!! . > > > > > > Unfortunately not work fine. > > > Rt=1,67nS (instead 300pS) > > > Width pulse= 5,84nS (wave exponential decay instead rectangular pulse) > > > Max out= 3,5V (instead 25V) > > > Rep Rate=15Mhz (instead 50 or 100Khz) > > > > > > The ratio of different att step, seems to be good. > > > Probability arise that my previous intuition about bipolar avalanche transistor burned out come truth. > > > > > > Perhaps the out pulse I see is not else than the trigger pulse passing trough a short avalanche transistor. > > > Any way, this nice generator will be fixed (tomorow)....all kind of help & advice will be welcome. > > > Gabriel...from the Holly land of Francisco Pope!!..God bless all of Us. > > > > > > > > > --- In TekScopes@..., "iglesia_cristiana_arpas_eternas" wrote: > > > > > > > > Here the link to this almost new pulsed generator, at first glance is a > > > > transmission line pulser with 300ps ..but no model or number at all. > > > > I just brought it with the hope work right...but a good service manual > > > > will be very appreciated and gratefully. > > > > Link to Pulse Gen. > > > > <http://www.ebay.com/itm/TEKTRONIX-HIGH-AMPLITUDE-PULSE-GENERATOR-/25123\ > > > > 2112187?autorefresh=true&pt=LH_DefaultDomain_0&hash=item3a7e99ce3b&nma=t\ > > > > rue&si=w4%252BkkAkTYIq9sTkPYLC8H98HEpU%253D&orig_cvip=true&rt=nc&_trksid\ > > > > =p2047675.l2557> > > > > > > > > Regards Gabriel. > > > > > > > > > > |
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Re: Need help with P6133
I pushed it out the back. I remember I also used a very small hammer, sometimes called a 'tap' hammer and lightly tapped on the needle nose while it gripped the hook. Note: the part of the hook that is inside has small protrusions that keep it in. The slot edges in the plastic case will deform slightly as you tap out the hook. With care, it will come out, and can be reinserted. Probably not a good repair for a production shop, but for a hobbyist it will work for awhile.
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Bob --- In TekScopes@..., "tonyp2422" <tonyp2422@...> wrote:
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Re: Need help with P6133
Thanks Bob. You pulled the hook out from the front? Or did you push it out the back?
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--- In TekScopes@..., "Robert" <go_boating_fast@...> wrote:
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Re: Tektronix jewelry
I believe that it's a real employee award/gift item, but it's nothing special, jewelry-wise. I believe that "gf" indicates "gold-filled," a euphemism for gold plated. The corrosion on the chain links shows the classic green from copper - either from the base plating to put the gold on, or from a brass alloy base material. The weight of the piece is irrelevant - it's a base alloy with a thin 12 k (50%) gold plating.
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Ed --- In TekScopes@..., "Tom Miller" <tmiller11147@...> wrote:
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Re: Tektronix jewelry
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Re: Need help with P6133
It may be possible to repair this. I have a spring hook tip that has the flat type of hook that had a similar problem. I used a needle nose pliers to push the hook tip out. I found the inside end is kind of shaped like a spade connector. It had spread apart from use and no longer made contact with the probe tip. Using a second pliers to keep the metal flat, I squeezed the splayed end back together. I tested the connect with the prob tip before I forced it back inside the plastic case.
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Note there is also a spring inside. Bob --- In TekScopes@..., "tonyp2422" <tonyp2422@...> wrote:
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Re: Tektronix jewelry
¿ªÔÆÌåÓýInteresting...
Very unique. Unusual tektronix item. Does anyone know the back story? Item # 251198997978 ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: (Yahoo! ID required) <*> To change settings via email: TekScopes-digest@... TekScopes-fullfeatured@... <*> To unsubscribe from this group, send an email to: TekScopes-unsubscribe@... <*> Your use of Yahoo! Groups is subject to: |
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Re: 2440: GPIB
¿ªÔÆÌåÓýGood points all around.
I assume ibnotify() is the windows version of the linux kernel inotify?? I was too deeply exposed to inotify when using and debugging icrond.? It was then that something snapped and I was forever altered. If I were to consider using GPIB for custom work, ibnotify() support would be worth considering.? Now that I think of it, I'm not :)? So maybe the prologix or a usb solution is best. I'm rather interested in building my own.? Has anyone built the Elektor adapter published in 2010? /m On 03/19/2013 01:34, Chuck Harris wrote: ? |
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Re: New 466 owner
Tom Jobe
¿ªÔÆÌåÓýThanks Tom,
Your suggestion about applying some oil worked perfectly on
the vertical VAR pots of this 465!
tom jobe...
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Re: 2440: GPIB
Say what! The patent office ALLOWED a patent for that ???? That is INSANE. Talk about not allowing for prior art.
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Dave -----Original Message-----
From: TekScopes@... [mailto:TekScopes@...] On Behalf Of John Miles Sent: 19 March 2013 01:31 To: TekScopes@... Subject: RE: [TekScopes] 2440: GPIB Nothing stops you from implementing ibnotify() on a background thread. (Well, nothing except National Instruments' patent on the concept of a callback function tied to a GPIB event.) -- john, KE5FX |
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Re: How to upgrade a 7854 to opt 2D
FWIW you can order Analog Devices SW06GPZ online direct from Analog Devices online throught their sample program ...
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Regards, David Partridge -----Original Message-----
From: TekScopes@... [mailto:TekScopes@...] On Behalf Of David Sent: 19 March 2013 00:36 To: TekScopes@... Subject: Re: [TekScopes] Re: How to upgrade a 7854 to opt 2D I remember the thread where this was discussed. If an SW06 was used to replace the LF13333, then I think the timing problem could be fixed by altering capacitors C2310, C2400, and C2300 a little bit to adjust the delays but since the SW06 analog switch is even less available than the LF13333, the easiest solution would be to just buy a couple of the original part. |
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Re: Sony/Tektronix 318 - UPDATE - got startup routine
--- On Sun, 3/17/13, Chuck Harris wrote:
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Re: 2213 PS Voltages All Too High
Did you checked the supplys for ripple voltge with a scope ? If ripple if excessive the DC can look higher for your multi meter. Is adds the average AC from the ripple to the DC.? Fred PA4TIM Op 19 mrt. 2013 om 03:46 heeft "Philip" <ndpmcintosh@...> het volgende geschreven:
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Re: Replacement to DS1230AB Lithium backed NVRAM
On Tue, 19 Mar 2013, lazystrings wrote:
There are even more exotic devices that are not available and worth rebuilding from discrete chips. DS1250Y is 4MByte device so no wonder it is expensive. But it easily replaceable with a small board with several chips and lithium battery. DS1486 is exotic so it is also worth rebuilding. But people were not talking about those. They were trying to rebuild readily available $15 chips used in older scopes. That doesn't make sense. Not all the Dallas Semiconductor NVRAM are available, some of them are--- * * KSI@home KOI8 Net < > The impossible we do immediately. * * Las Vegas NV, USA < > Miracles require 24-hour notice. * * |
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Re: 2440: GPIB
Chuck Harris
Their I/O model is USB, and with it comes most of USB's gifts and
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problems. If you want to use it asynchronously, set up a task to poll it in the background. That way your programming sensibilities won't be offended. It's not like you won't have to be doing some polling somewhere in your GPIB software no matter what the board. There are thousands of us that think the prologix unit is just ducky for running our ancient HPIB equipment. But, then we are all wrong, and only you are right. -Chuck Harris David Gravereaux wrote: I advice AGAINST the prologix adapters. Their I/O model is garbage.. |
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Re: 2213 PS Voltages All Too High
This is opposite the usual problem of having something overloaded by a bad cap or rectifier, for example. If all of the secondaries are in the correct proportions, then look to the chopper stage. As I recall, there is a regulator loop that measures the collector voltages via diodes, feeding back to an analog loop that sets the on-ness of the chopper transistors, which in turn sets the transformer primary voltage - the secondaries are indeed regulated by virtue of the primary voltage.
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On some 2200 models there is instead a series pass MOSFET that provides the equivalent function. Either way, the primary voltage is what's regulated by the control loop. A bad (open) collector voltage sampling diode, for example, could make everything too high by not contributing its share of feedback signal, while the working one still allows it to get close. Or, there could be a control loop failure that forces the output to the maximum value. Study the circuit to see what it should do - some simple DVM measurements should point the way without needing to scope it or worry about isolation. As long as it runs - sort of - DC measurements should be enough to diagnose the control loop function. If this fails, and it is necessary to isolate the stage, there is a common trick that many have used, powering the chopper stage directly from a DC supply, without using the line-powered preregulator of the scope. There are lots of references to this in the archives. Ed --- In TekScopes@..., "Philip" <ndpmcintosh@...> wrote:
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Re: Replacement to DS1230AB Lithium backed NVRAM
Not all the Dallas Semiconductor NVRAM are available, some of them are obsolete or they are very expensive.
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The DS1250Y costs between $58 and $62 if is in stock. The DS1486 is not available from reliable sources. Those 2 parts are used on most of the TDS6xx scopes :( --- In TekScopes@..., "Rob" <rgwood@...> wrote:
?€?I cannot understand guys, WHY BOTHER??€?<<<< |