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Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace
Dave Brown <tractorb@...>
Dennis
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How many of the 7 and 9 pin plugs do you need? Are you looking for a significant number? 73 Dave, ZL3FJ
-----Original Message-----
From: TekScopes@yahoogroups.com [mailto:TekScopes@yahoogroups.com] Sent: Monday, March 27, 2017 3:46 PM To: TekScopes@yahoogroups.com Subject: RE: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Hi Bill, In my case I needed tube PLUGS that would plug into a tube SOCKET. That is my problem. I am well aware of Tubesandmore. They certainly have a nice selection of 4 pin, 5 pin, 7 pin, 8 pin , and 9 pin tube SOCKETS. Unfortunately other than 8 pin tube PLUGS they, or anyone else for that matter, do not sell 7 pin miniature tube PLUGS or 9 pin miniature PLUGS. Since 7 pin miniature tubes and 9 pin miniature tubes have their pins coming right out of the glass envelope this will make it very hard to get what I need by smashing spent tubes to try and get an intact set of pins around the base of the tube. As John Gord pointed out one way to find some of these is by searching for socket savers. They, too, are scarce these days. Not many people are designing things with tubes. There was a 9 pin and a 7 pin socket saver auction on Ebay and I bid $28 for them but someone outbid me. I have no way to know how high that person's ultimate bid might have been. Dennis Tillman, W7PF -----Original Message----- Sent: Sunday, March 26, 2017 5:08 PM Subject: Re: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Dennis and all, Has everyone been overlooking the best source for tubes and related hardware? https://www.tubesandmore.com/products/tube_accessories Bill KB3DKS -----Original Message----- From: 'Dennis Tillman' dennis@ridesoft.com [TekScopes] <TekScopes@yahoogroups.com> Sent: Wed, Mar 22, 2017 10:06 am Hi John, Thanks for the suggestion. I know I kept coming across octal socket savers all the time but I never saw a 7 pin or 9 pin socket saver. I will give that a try. Dennis Tillman W7PF -----Original Message----- Sent: Tuesday, March 21, 2017 5:06 PM Subject: RE: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Try a Google search for "7 pin socket saver". I got some hits. 9 pin socket savers seem to be more common. It looks like at least some of the socket savers could be disassembled. --John Gord ------------------------------------ Posted by: Doxemf <doxemf@aol.com> ------------------------------------ ------------------------------------ Posted by: "Dennis Tillman" <dennis@ridesoft.com> ------------------------------------ ------------------------------------ Yahoo Groups Links
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Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace
stuff that disappears does so for a reason. Maybe you just simply
don't get tubes with that base that are any interesting at all. No point trying to accumulate stuff that's boring other than it has a specific pinout. On Mon, Mar 27, 2017 at 6:56 AM, 'Dennis Tillman' dennis@ridesoft.com [TekScopes] <TekScopes@yahoogroups.com> wrote: Hi Cheater,
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Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace
Hi Cheater,
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In a pinch I did make a 9 pin plug using 0.040" bus bar pushed into an existing 9 pin socket, with a piece of PVC tubing around it, and I potted the entire thing. What you get is crude, and it takes a fair amount of time to do this. So this is hardly a reasonable solution except in a pinch. I was hoping for something that was much more professional and took far less time. I don't mind paying $10 for a plug that I can order from somewhere. Some of the tube stuff seems to have disappeared, and other stuff seems to be doing just fine. I haven't figured out which stuff is rare that I should jump at them whenever they show up versus the stuff that is still very common and still being produced. I'm new to the whole tube world. Last time I touched a vacuum tube was 40+ years ago until very recently. Dennis Tillman W7PF
-----Original Message-----
Sent: Sunday, March 26, 2017 9:29 PM Subject: Re: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Am I missing something... why not just take a bare FR board and drill some holes in it.. use two boards for rigidity... and pot the whole job? On Mon, Mar 27, 2017 at 5:42 AM, Doxemf doxemf@aol.com [TekScopes] <TekScopes@yahoogroups.com> wrote: Dennis,------------------------------------ Posted by: cheater00 cheater00 <cheater00@gmail.com> ------------------------------------
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Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace
Am I missing something... why not just take a bare FR board and drill
some holes in it.. use two boards for rigidity... and pot the whole job? On Mon, Mar 27, 2017 at 5:42 AM, Doxemf doxemf@aol.com [TekScopes] <TekScopes@yahoogroups.com> wrote: Dennis,
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Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace
Bill (Doc) Courtright
Dennis,
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They have the 9 pin Socket Savers. I did not see any 7 pin. Quite awhile ago there were some cheap car stereo players, maybe eve 8 tracks, I forget, I serviced them once. Anyway, they used a 9 pin male/female connector. I think that the old Calrad or similar brand offered the cable sets. Fair Radio used to have some as well. Someone with a 3D printer could probably spit a bunch out that way. Just have to provide the pins. Bill, KB3DKS
-----Original Message-----
From: 'Dennis Tillman' dennis@ridesoft.com [TekScopes] <TekScopes@yahoogroups.com> To: TekScopes <TekScopes@yahoogroups.com> Sent: Sun, Mar 26, 2017 10:46 pm Subject: RE: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Hi Bill, In my case I needed tube PLUGS that would plug into a tube SOCKET. That is my problem. I am well aware of Tubesandmore. They certainly have a nice selection of 4 pin, 5 pin, 7 pin, 8 pin , and 9 pin tube SOCKETS. Unfortunately other than 8 pin tube PLUGS they, or anyone else for that matter, do not sell 7 pin miniature tube PLUGS or 9 pin miniature PLUGS. Since 7 pin miniature tubes and 9 pin miniature tubes have their pins coming right out of the glass envelope this will make it very hard to get what I need by smashing spent tubes to try and get an intact set of pins around the base of the tube. As John Gord pointed out one way to find some of these is by searching for socket savers. They, too, are scarce these days. Not many people are designing things with tubes. There was a 9 pin and a 7 pin socket saver auction on Ebay and I bid $28 for them but someone outbid me. I have no way to know how high that person's ultimate bid might have been. Dennis Tillman, W7PF -----Original Message----- Sent: Sunday, March 26, 2017 5:08 PM Subject: Re: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Dennis and all, Has everyone been overlooking the best source for tubes and related hardware? https://www.tubesandmore.com/products/tube_accessories Bill KB3DKS
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Re: 7912AD Repair
Bill Higdon
Should have been down not sown
Bill
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Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace
Hi Bill,
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In my case I needed tube PLUGS that would plug into a tube SOCKET. That is my problem. I am well aware of Tubesandmore. They certainly have a nice selection of 4 pin, 5 pin, 7 pin, 8 pin , and 9 pin tube SOCKETS. Unfortunately other than 8 pin tube PLUGS they, or anyone else for that matter, do not sell 7 pin miniature tube PLUGS or 9 pin miniature PLUGS. Since 7 pin miniature tubes and 9 pin miniature tubes have their pins coming right out of the glass envelope this will make it very hard to get what I need by smashing spent tubes to try and get an intact set of pins around the base of the tube. As John Gord pointed out one way to find some of these is by searching for socket savers. They, too, are scarce these days. Not many people are designing things with tubes. There was a 9 pin and a 7 pin socket saver auction on Ebay and I bid $28 for them but someone outbid me. I have no way to know how high that person's ultimate bid might have been. Dennis Tillman, W7PF
-----Original Message-----
Sent: Sunday, March 26, 2017 5:08 PM Subject: Re: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Dennis and all, Has everyone been overlooking the best source for tubes and related hardware? https://www.tubesandmore.com/products/tube_accessories Bill KB3DKS -----Original Message----- From: 'Dennis Tillman' dennis@ridesoft.com [TekScopes] <TekScopes@yahoogroups.com> Sent: Wed, Mar 22, 2017 10:06 am Hi John, Thanks for the suggestion. I know I kept coming across octal socket savers all the time but I never saw a 7 pin or 9 pin socket saver. I will give that a try. Dennis Tillman W7PF -----Original Message----- Sent: Tuesday, March 21, 2017 5:06 PM Subject: RE: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Try a Google search for "7 pin socket saver". I got some hits. 9 pin socket savers seem to be more common. It looks like at least some of the socket savers could be disassembled. --John Gord ------------------------------------ Posted by: Doxemf <doxemf@aol.com> ------------------------------------
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CORRECTED POST : Tek 2445 vs Tek 2430A (Tek 2435A)
I have 3 Tek 2445 scopes and one Tek 2430A scope. While idly bumming around eBay, I noticed that it seemed to me the 2445s were less common and on average more expensive than the 2430As. Seeing as how the 2430A is a DSO and the 2445 is analog I would have expected the opposite. Am I wrong in this thinking or am I missing something?
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Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace
Bill (Doc) Courtright
Dennis and all,
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Has everyone been overlooking the best source for tubes and related hardware? https://www.tubesandmore.com/products/tube_accessories Bill KB3DKS
-----Original Message-----
From: 'Dennis Tillman' dennis@ridesoft.com [TekScopes] <TekScopes@yahoogroups.com> To: TekScopes <TekScopes@yahoogroups.com> Sent: Wed, Mar 22, 2017 10:06 am Subject: RE: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Hi John, Thanks for the suggestion. I know I kept coming across octal socket savers all the time but I never saw a 7 pin or 9 pin socket saver. I will give that a try. Dennis Tillman W7PF -----Original Message----- Sent: Tuesday, March 21, 2017 5:06 PM Subject: RE: [TekScopes] Re: A Vacuum Tube Curve Tracer for all Tek Semiconductor Curve Trace Try a Google search for "7 pin socket saver". I got some hits. 9 pin socket savers seem to be more common. It looks like at least some of the socket savers could be disassembled. --John Gord
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Re: Tek 2445 vs Tek 2435A
Chuck Harris
The 150MHz 2445 came out concurrent with the 300MHz 2465,
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costing $3250 vs the 2465's $4750. Double the performance, and only a third more in price. More the wonder is why any sold at all? -Chuck Harris houdatto@gmail.com [TekScopes] wrote:
I have 3 Tek 2445 scopes and one Tek 2435A scope. While idly bumming around eBay,
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Re: 7912AD Repair
Bill Higdon
The Little Mountain part/Annex of Hill AFB has an interesting history. originally it was a specially built wind tunnel for testing the Ramjet engines for the Bomarc. After that program shut sown it was dormant for a period of time until the Air Force realized they needed to move the High energy X Ray system to some place where the particle beams didn't have a chance of hitting people like they did when they were on Hill AFB proper. So they moved them to the Little Mountain facility. They're on the west side of the the mountain, follow the road past Moulding and sons landfill.
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Re: Intro & Tek 2235 - Momentary trace only with dim bulb tester
A Rob
Voltages at Q114 & Q115 stay exactly the same when switching between ch1 & ch2.
I have double checked voltages and there is a slight difference to what I'd previously reported: U130 Pin 13 1.97 Volts Selected U130 Pin 13 2.79 Volts Not Selected U130 Pin 9 2.49 Volts Selected U130 Pin 9 2.78 Volts Not Selected U130 Pin 7 0.00 Volts Selected U130 Pin 7 -0.01 Volts Not Selected U130 Pin 14 0.74 Volts Selected U130 Pin 14 -0.59 Volts Not Selected R143 is reading as 98.62ohm in circuit L143 is reading 0.01ohm in circuit
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Re: 2465 Vertical Gain
Chuck Harris
The 2465B stores all of the offsets, and gain changes necessary
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to make the scope in calibration in the NVRAM that is on the A5 board. The only adjustment pots are in places where a resistor must be a resistor, not a computer generated voltage. It takes a full vertical recalibration to fix your problem. -Chuck Harris greg_knox@bellsouth.net [TekScopes] wrote:
The CH 2 vertical gain on my 2465b is a few percent off, relative to the CH 1
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Re: 7912AD Repair
Roger Evans
Chris,
The digitised output only appears on the XYZ connectors, I use a 485 in XY mode and found that the Z connection did not add anything useful. When I press the digital button. Tha analogue monitor goes black and two seconds later the digitised signal appears on the XY monitor. Subsequently pressing the digital button gives a new digitised trace immediately. The manual says the first two second delay is to allow voltages to stabilise. The same thing happens when you give commands via GPIB. I have a home made USB to GPIB interface and can store data and view images on a PC. Apart from the elation of getting the 7912 to work there is now the question of what to do with the enormous box in the corner! Roget
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Re: 7912AD Repair
cmjones01
On Sun, Mar 26, 2017 at 9:04 PM, very_fuzzy_logic@yahoo.com [TekScopes] <
TekScopes@yahoogroups.com> wrote: amplifier wasn't working due to, you've guessed it, yet another short-circuit tantalum on the -15V rail which had taken out its 10R decoupling resistor. I replaced both and the remaining tants on that board, and now I have a proper scan, with graticule and waveform! The focus control on the front panel has little effect on my 7912AD, thevery similar way: when it's not optimally set, the trace and graticule look a bit dim and ill-defined rather than fuzzy in the way they would on a standard analogue scope. I can get a sharp trace and graticule with the focus control at mid position and experience the blooming if I crank up either intensity too much. What I was seeing before was *all* blooming because I had no X read scan! Sounds like you should have a working 7912 soon!Yes, I think we're almost there. I'm not sure if the digitiser is working properly. I have a monitor connected to the linear TV out (the binary one also works but is harder to use for adjusting everything). I can see the trace and graticule. There seems to be some hum on the trace but that could be due to an earth loop and having the cases off everything. When I press the 'digital' button the screen goes white. I read in the manual this morning that a digitisation takes 2 seconds, and so I should probably be more patient: presumably I should see the frozen waveform on the monitor after that. I haven't tried the XYZ output yet. I do have a full 'doorstep' set of paper manuals, thanks to a fortuitous visit to Manuals Plus a week or so before they closed down. They're labelled 'Hill AFB - Little Mountain', so I bet they could tell a few stories. Chris
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Re: 7912AD Repair
Roger Evans
Chris,
The fastest sweep speeds need the x10 magnifier so you will have an apparently wide scan. On the 7B90P there is a 'mag' led that comes on. The graticule should show 10 x 8 equal squares so that would confirm that the read scan size is correct. The focus control on the front panel has little effect on my 7912AD, the spot blooms very quickly if the brightness is too high but is sharp at the lowest usable intensity. The Z axis amplifier is driven differently for the graticule and the sweep and mine struggles to show sharp trace and graticule at the same time. For serious use you would digitise the graticule separately, I believe the software is supposed to calculate the centroid of each graticule spot. The required intensity for a good trace varies a lot with sweep speed and rep rate. Also the cpu will limit the maximum Z axis drive at lower sweep speeds, I would try making small adjustments to the Grid Bias to get good results for a repetitive 10ns/div sweep with no more than one turn of the write intensity pot. You should then be able to digitise single sweeps with the intensity turned right up. There is a formal Z axis calibration but I have slightly low output from the Z amplifier so I opted for the trial and error approach. I would strongly recommend turning the intensity right down before you turn the 7912 on as a matter of habit. Sounds like you should have a working 7912 soon! Regards, Roger
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Last minute stuff requests while dennis is here
Dennis and Aris are up here at sphere this weekend, he is bringing back the little meters, and the 570 meter, any other requests? we need to know in the next few hours.
I also have clean working 465M vertical/horizontals for $25 each, 11K , 5K, 2/3 series and other plug ins. this is a chance to get them down there with no freight. bad plug ins are $5/$10. You can email me off list at walter2 -at- sphere.bc.ca or call us at 1-250-769-1834. we will be out for breakfast from 10 to 11am. -walter sphere research corp.
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Re: Meanwhile in Austria
Wow... That's cool!!!!... And the way he made for the shapes to "sing" as
well! Awesome! On Mar 26, 2017 7:00 AM, "Stefan Trethan stefan_trethan@gmx.at [TekScopes]" <TekScopes@yahoogroups.com> wrote:
[Non-text portions of this message have been removed]
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Re: OT: Where to get a good isolating transformer + HV isolation materials?
Hi David,
On Sun, Mar 26, 2017 at 3:37 PM, David davidwhess@gmail.com [TekScopes] <TekScopes@yahoogroups.com> wrote: On Fri, 24 Mar 2017 04:39:49 +0000, you wrote:Wouldn't a nylon spacer be plenty enough? Just some nylon struts, 1Ah great, I didn't know that Bel transformer could be used like this!Yes, but ... inch to several inches in length, covered in corona dope? If leakage is not a problem, then a resistor-capacitor voltage divider Welp... leakage IS a problem... because you need the leakage to be below a current that will kill you, and that's not a lot!!! It's the voltage that gets you, but it's the current that kills you! So, say, a spark gap is out of the question. But maybe a very low current, high voltage rated incandescent could work? I wonder, at 10 kV, what sort of current this would entail... Also I wonder if this sort of thing would be safe... say you made a circuit that allows current only run across the first OR the second transformer but not both... would that entail safety? I think it wouldn't... but I'm not sure.
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Re: 2465 Vertical Gain
Gain control is through the vertical preamplifiers so it has to be
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done electronically. Maybe just the channel 2 vertical gain adjustment procedure can be done?
On 26 Mar 2017 12:28:36 +0000, you wrote:
The CH 2 vertical gain on my 2465b is a few percent off, relative to the CH 1 gain, which is right on. Is there an adjustment pot for this, or do I have to go through the whole calibration procedure to fix it? The scope passes all the power up self tests and works beautifully otherwise. Thanks.
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