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Re: Tek 492BP how to save via GPIB to a PC
Sounds like you either don't have the NI drivers installed, or the board ID is set to something other than GPIB0. What does the menu in GPIB configurator look like? If it doesn't show up as GPIB0 you'll need to select the correct board entry and hit 'Update CONNECT.INI' before you can use the programs with it. (Or you can change the board ID in the NI software, I believe.)
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-- john, KE5FX -----Original Message----- |
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Re: O.T. Digital scopes versus Tek analogue.
Thanks, I can't keep up with it. Ugh. It's really painful to see the remains of once-great companies be drones in a corporate army. =[
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Sean On Thu, Mar 4, 2021 at 11:11 PM, hardyhansendk wrote:
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Re: O.T. Digital scopes versus Tek analogue.
Fortive ows them all now.
Regards Hardy -----Oprindelig meddelelse----- Fra: [email protected] [mailto:[email protected]] P? vegne af Sean Turner Sendt: 5. marts 2021 07:56 Til: [email protected] Emne: Re: [TekScopes] O.T. Digital scopes versus Tek analogue. Jeff, An instrument called a "source measure unit" is what is typically sold these days as an instrument for curve tracing (and other purposes). Keithley (which is a Tektronix/Danaher subsidiary now) offers them, and they are ruinously expensive for the hobbyist (at least new). They have computer interfaces and programmability. I don't think any of the big T&M manufacturers offer a curve tracer any more. Since everything is either tiny surface mount or an ASIC or an FPGA nowadays, there's no demand. Logic analyzers are headed the same way. I think Keysight is the only company that offers a true benchtop logic analyzer anymore. Tek discontinued the TLA series and directs you to buy a mixed signal scope instead. Sean On Mon, Mar 1, 2021 at 01:55 PM, Jeff Dutky wrote:
-- Denne mail er kontrolleret for vira af AVG. |
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Re: O.T. Digital scopes versus Tek analogue.
Jeff,
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An instrument called a "source measure unit" is what is typically sold these days as an instrument for curve tracing (and other purposes). Keithley (which is a Tektronix/Danaher subsidiary now) offers them, and they are ruinously expensive for the hobbyist (at least new). They have computer interfaces and programmability. I don't think any of the big T&M manufacturers offer a curve tracer any more. Since everything is either tiny surface mount or an ASIC or an FPGA nowadays, there's no demand. Logic analyzers are headed the same way. I think Keysight is the only company that offers a true benchtop logic analyzer anymore. Tek discontinued the TLA series and directs you to buy a mixed signal scope instead. Sean On Mon, Mar 1, 2021 at 01:55 PM, Jeff Dutky wrote:
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Re: 547 HV Transformer: Bill Schell rewind failed
Hi Dave-
I'm sorry to hear that you're having trouble with that HV XFMR.... I did a lot of testing and evaluation for Bill Schell over the years and I don't remember him every testing a transformer with any epoxy in it at all. He and I both felt that we oughta get as far away from that as possible. He first wound them without sealing them and I have never had one of those fail. Then when he started treating them with beeswax and a vacuum chamber, it seemed like he had found quite a good process. So far, I have never had one of his fail, of any description. Just saw your later post and I'm glad that yours is improving! A friend of mine has restored an original xfmr by putting it in a vacuum chamber and keeping it in a deep vacuum for a while. Don't remember how long he left it in there. I hope yours comes out alright. It really does seem like the moisture is the major factor. Tom |
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Re: 2235 AN/USM-488 power supply low voltages
Voltages as followsAll the voltages are about 86-88% of their target value. Especially -8.6V is the reference for all other supplies so if it is off by some percentage all others will be off by about the same percentage. "Power Supply and CRT DISPLAY" adjustment section (page 5-4) of the manual gives the steps for R938 trim which should fix -8.6V and all other supplies if there is no other fault. Ozan |
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Re: 547 HV Transformer: Bill Schell rewind failed
Chuck,
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Are you in need of bees wax? I might be able to get some in bulk. I happen to know a couple of bee keepers. I would also like to learn more about the transformer winder when the time is right. Eric On Thu, Mar 4, 2021, 7:45 PM Chuck Harris <cfharris@...> wrote:
Hi Bernd, |
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2235 AN/USM-488 power supply low voltages
I bought this scope earlier this summer as new old stock, never powered on. Due to covid illness I never opened it until a week ago. The scope powered on ,but the trace only covered about 2/3s of the screen and was jumping all over.
After it was warming up only got worse, I decided to check the voltages on the power supply and all were low. So I did a full recap (caps are still old even though the scope has zero hours) and also replaced the following: VR 901 Q935 Q946, 947 Q9070 R888,889,890,891,892 R900 and the ac filter all 3 rifa x class caps Same problem still exist Voltages as follows +5.2=4.3 +8.6=7.4 -8.6=-7.3 +30=+25.8 +100=+87.8 resistance to ground; +5.2=188oms +8.6=129.8 ohms -8.6=81 oms +30=552 ohms +100=16k ohms also the trigger led blinks when the scope is on. I have been reading all the power supply post here and frankly, I'm stumped This is my first attempt a troubleshooting a switch mode power supply. any and all suggestions would be greatly appreciated Thanks in advance R A |
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Re: Replacing Variable Vertical Attenuator Shaft
Dick,
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I parted out some 7000-series plug-ins that were not repairable. I believe I have some of those G-10 rods. They connect to pots via a coupler with two set screws. If that rod is what you need, let me look at what I have and I¡¯d be glad to send you one. If they are longer than 7¡±, it would be simple to cut it to length. You can contact me off list if you wish or reply here. My e-mail is: sonodocsch at gmail dot com. Steve Horii On Thu, Mar 4, 2021 at 20:47 Dick <w1ksz@...> wrote:
The shaft is a piece of G-10 rod that's about 7" long. It goes |
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Re: Replacing Variable Vertical Attenuator Shaft
Dick
The shaft is a piece of G-10 rod that's about 7" long. It goes
from the Front panel to a bushing buried in the Vertical Amplifier. I thought I would ask before I butcher the job. I am located in Vail, Arizona. About 20m SSE of Tucson. 73, Dick, W1KSZ ________________________________ From: [email protected] <[email protected]> on behalf of Waltzingbear <alan@...> Sent: Thursday, March 4, 2021 10:57 AM To: [email protected] <[email protected]> Subject: Re: [TekScopes] Replacing Variable Vertical Attenuator Shaft I bet that is an AB mod pot, in which case you can repair the pot with a new shaft part. What is the length of the shaft? oh, and what part of the world are you located in. Cheers Alan |
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Re: 547 HV Transformer: Bill Schell rewind failed
Chuck Harris
Hi Bernd,
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All indications are that my new machine is going to do an even better job than the best I could do with the old manual machine. As an example, I was able to get 2/3 of the way to a full wind without using the rosin/alcohol mixture that I developed to enhance the wire's friction... Using the rosin/alcohol, I am there already. And, I will be using beeswax. I'm glad to hear the prototype is still soldiering on. Soon, I may be able to get you the winds I promised oh so long ago... -Chuck Harris widgethunter via groups.io wrote: My memory certainly hasn't improved with age.Not much else seems to have, either...But, the beeswax thing I'd be willing to put money on - fwiw. |
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Re: 547 HV Transformer: Bill Schell rewind failed
widgethunter
My memory certainly hasn't improved with age.Not much else seems to have, either...But, the beeswax thing I'd be willing to put money on - fwiw.
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Incidentally, I still have not installed the 2nd wax xfrmr you made for me, but the 1st prototype continues to perform flawlessly.Bernd -----Original Message-----
From: Chuck Harris <cfharris@...> To: [email protected] Sent: Thu, Mar 4, 2021 4:05 pm Subject: Re: [TekScopes] 547 HV Transformer: Bill Schell rewind failed Hi Bernd, I guess the biggest indicator of a scatter wind would be the presence of a spool.? The universal wind doesn't require any additional support. In addition to talking to you, I talked to Deane Kidd, and Deane talked about Bill using beeswax, like tektronix did in the earlier transformers. But, like you, it has been a looong time, and I don't think our memories are getting any better. -Chuck Harris widgethunter via groups.io wrote: Hi Chuck;Assumed scatter because of the larger size of Schell rewinds.It has been a looong time, but I think I'd remember if he'd said anything about epoxy...B |
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Re: 547 HV Transformer: Bill Schell rewind failed
Chuck Harris
Hi Bernd,
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I guess the biggest indicator of a scatter wind would be the presence of a spool. The universal wind doesn't require any additional support. In addition to talking to you, I talked to Deane Kidd, and Deane talked about Bill using beeswax, like tektronix did in the earlier transformers. But, like you, it has been a looong time, and I don't think our memories are getting any better. -Chuck Harris widgethunter via groups.io wrote: Hi Chuck;Assumed scatter because of the larger size of Schell rewinds.It has been a looong time, but I think I'd remember if he'd said anything about epoxy...B |
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Re: 547 HV Transformer: Bill Schell rewind failed
Roger:
If's beeswax (It could be paraffin wax, or a silicone wax, or some other wax type potting...or not even wax) If it's beeswax... and you want to verify... put a tiny scraping of it in a spoon, and hold it in the steam of a boiling kettle... it will soon melt. Also, beeswax has a pleasant fragrance. -- Roy Thistle |
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Re: 7104 readout issue
Sean,
A friend of mine found a burned resistor and bad TO-5 metal can transistor on the Readout Board in a military version of the 7603. The R was 3.9k, the TO-5 can something like a 2n2905 or 2n3440 with an OEM number. Maybe examine / check for those parts, if that transistor loses beta over time, it may overheat the R, then self destruct causing a loss of display. Steven |
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Re: Tek 2782
Hi Steve,
I can think of a few possibilities... maybe the tilting caused something to short, blowing a fuse or some circuitry. Maybe a board became disconnected. Maybe a PS line got pulled from its connection. Maybe a board became warped and hit ground, damaging surge blew out a circuit or fuse. Maybe the socket on the CRT lost connection to its pins... pull anything and clean contacts gently, look for item in contact with the case or ground, check fuses, test PS capacitors, try again! Steven |
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Re: [Tek 485] No intensity control
I see ~42mV at collector of Q1548, no dot on screen in XY Mode.Look OK. CR1539 is ok : ~.6V and 0LLooks OK. R1536 measured in circuit gives : 300kohm and 100kohm (when inverting the testThis is a very large resistor, you won't be able to get a good read without removing a leg. I recommend checking C1537 first, see below. I just noticed C1537 is an electrolytic cap although its value is small. It could have developed a small leakage. If you remove it do you see any difference? Ozan |
Mike Yepes
Waltzingbear
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