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Re: 466-464 stray wire
Hello Jim,
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I`m glad I was helpful. On your comments about taking out the big capacitors, I can't be more glad that you didn't have problems. you're either very lucky, or very, very good with the solder sucker (or both). I had to do the same on mine, I consider myself very good at desoldering using a solder sucker and always did this kind of job on double-sided, through-hole plated boards without hassle... and I had a real bad time taking mine out. I lifted at least 3 or four pads from the capacitor side, and stripped out an equal number of through-hole vias. It was a real pain to put it back together, without having to make ugly wire jumpers. (I used tiny bits of component leads and wires, to make back the connections between both sides, using the available space around the capacitor pins, sometimes making the pins a bit thinner, to make room for the interconnecting wires inside the holes. Nevertheless, since you mentioned that you had to wiggle them a little bit for them to come out, I recommend you make a careful inspection of all the through-hole vias and make sure they're in good shape. The adhesive that sticks the copper to the board on those ancient boards are not top notch compared to modern boards and they won't stand a second desoldering session so, you don't want to be forced to take them out once again, just because you overlooked some through-hole via. Regarding your question about C1713 (couldn't find a C1712), when I got my 464 on 2016, this one was already replaced by an aluminum electro (of 25V). This fact gives room for assumption that the original Tantalum of 25V failed in that position, and I wouldn't hesitate in shuffling a 35V tantalum, or even a regular aluminum electrolytic there. However, in face of the majority of other Tant caps that are infamous for failing in those scopes (of which Tek sometimes would use a 15V cap on a 15V rail), this one spec'd at 25V is not so badly spec'd after all. This winding of the transformer seems to be something about 10Vac, and it puts just about 14V (rectified) across this capacitor so, I think that even 25V there will do fine but, if you can fit a 35V capacitor there, it's the best case scenario. Ah... in time... if what you're worried about this, is that it's a 25V cap on a +140V supply (actually +154 unreg)... no fears... it's hooked to the +140V supply at its negative side so, it only "sees" the difference (which is about 14V). Rgrds, Fabio On Mon, Jul 23, 2018 at 05:42 PM, Jim Olson wrote:
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Re: OT: HP 70843B Error Performance Analyzer, 12 GHz BERT info needed
Here is a list of the GaAs logic ICs used in the mux and demux modules. There are 12 pieces in each. I have found data sheets for a few, as shown, and a little descriptive stuff, and made some guesses based on the circuit topology. They were all made by NTT in the 1990s. If anyone knows of other info to fill in the blanks, it would be great.
TX 8:1 MUX NL4515, 4pcs, no data, probably 2:1 mux, few GHz NL4520-2, 1pc, have data - 3 GHz 1:2 clock distribution NL4508, 1 pc, no data, probably a FF, few GHz NLG4115, 3pcs, have data, 2:1 mux, 10 GHz NLG4108, 2 pcs, no data, apparently 14.5 GHz TFF, used as clock divider NLG4120, 1 pc, have data, 10 GHz 1:2 clock dist RX 1:4 DEMUX NL4506, 4 pcs, no data, probably few GHz 1:2 demux NL4508, 1 pc, same as in MUX NL4519, 1 pc, have data, 8 GHz 2-inp NAND, used as buffer NLG4108, 1 pc, same as in MUX NLG4120, 3 pcs, same as in MUX NLG4104, 2 pcs, no data, probably 10 GHz 1:2 demux It appears the NLG series are for full-speed sections around 10 GHz, while the NL series are slower, in the few GHz range. The HP70843B is spec'd to 12 Gbps, but probably at lesser performance beyond 10, or at high temperatures. Ed |
Re: 7603 specifically and general refurbishment procedures of older oscilloscopes
Hi John,
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There are a few things you could do before opening the cabinet. It's possible that the scope is working normally but showing no trace because of a fault in the (un)blanking circuitry. You might check the signals at the rear panel BNC output connectors (Vert Sig Out, Gate Out, Sawtooth Out) to see if there is activity inside. An (un)blanking fault could be present in the path from 7B plugin to/through the main interface board. I think, but I have no 7603 to test this myself, that the CRT will be unblanked anyway when you try the 7603 in XY mode using two 7A plugins. (Try this unfocused to avoid phosphor damage.) The dot position should listen to position controls. Albert On Mon, Jul 23, 2018 at 05:57 PM, <johnasolecki@...> wrote:
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Re: 466-464 stray wire
Thanks Fabio for the reply. I opened my PDF copy of the 464 manual and found the +15 volt end of the wire on the TRIG-VIEW switch but didn't know where it went from there. Did some careful perusing of the TRIG-GENERATOR SWEEP BOARD and found it at the bottom as you descibed it so then after I got my early 466 manual searched it out and found it also.
Appreciate the description of the circuit and also the chip diffs i have started to put together the list of capacitors I am going to need and have pulled the 6 caps from the interface board for the 466 I did not have any real problem getting them off was a bit hesitant at first because of the horror stories on here from folks doing that. Some time back I picked up a real nice desoldering tool from Radio Shack it is a bulb sucker type with the bulb attached above the handle and to the tip with a tube so you can put the tip on the connection to be unsoldered and when soft just release the bulb cleans off and out all the solder. Once I got the first one out it was easy to see how they were attached just put the tip hole down over the small pins first sucked out the solder so they were loose the worked on the big one wiggling the cap while heating took two three time to get it loose big hole filled up with solder on that one. Have a question on two of the tant caps used in the power supply for one section of the output they are two 47uf 25v caps # 1712 & 1713 they are in a half wave rectified section and across the output for the +140v supply it seems that 25v is a bit low here? Any comments here? Jim |
Re: Homemade tunnel diodes
For the purposes of harmonic generation NLTLs have much lower PN than SRDs.
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Bruce On 24 July 2018 at 05:37 thespin@... wrote: |
Re: 466-464 stray wire
Hello Jim,
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I used to owe a 464 that I refurbished completely, it had a DM44. I don't possess it anymore as I gave it as a gift to a friend... I disassembled the Vertical Pre-Amp board and the Triggering board quite a few times and remember quite well of this wire. I'm not sure at what revision of manual and or schematic you're looking, but on the 464 manual that I have, it's really easy to spot this connection at both its ends. On diagram 3, VERTICAL SWITCHING, it's on the right side, a little bit above half of the page. from top to bottom, it's the first outgoing connection just after the outputs to the delay line, coming out from one of the ganged switches actuated by the TRIG-VIEW button. It gets connected to +15V when TRIG-VIEW is pressed, and it goes to R691 on diagram 5. On diagram 5, A&B TRIGGER GENERATOR, this connection show on the very bottom of the page, just above the "A&B TRIGGER GENERATOR <5>" diagram title. When the TRIG-VIEW button is pressed, the +15V coming through this wire is what actually provides power to the TRIG-VIEW output buffer, which will source the TRIG-VIEW signal. It's not clear to me though, why Tek chose to switch the power going to this small output stage, since its output is further switched by the remaining contacts of the TRIG-VIEW switch. On the 466, I have only a PDF copy of a later revision (whose channel select circuitry is similar to the 465B and 468) and there doesn't seem to exist this wire, as the whole TRIG-VIEW circuitry is completely different. On the 465, at the source of the signal (red wire) it's represented exactly the same as I described above for the 464, and in the same location of the VERTICAL SWITCHING <3> diagram, with the only difference that the wire is not connected directly to the board, but by means of a connector pin, P337. Yet on the 465, at the other end of this wire, it's different from the 464 schematics, because Tek chose to draw the Trig-View amplifier on a different diagram <11>, and there are a few differences in what the +15V coming through this wire actually does. On the 465, it only apply bias to the Trig-View amplifier input transistors (while the output transistors get continuous +15V supply). Regarding the scope being with DM44 or without it, I don't think it matters whatsoever to this circuit. Last but not least, regarding the two different versions of the custom Triggering Amplifier IC, 155-0032 or 155-0217, I don't think it matters if with or without DM44t... There's nothing about this IC that holds any relation to the DM44 being installed or not. When I got my 464, its trigger was not working well, and it had 2 different versions of this IC (A time base had the older, B time base had the newer). It was one of my first questions to this group, back on 2016, whether there was any difference between them (that could justify my A trigger was not working well) but soon enough I discovered that my problem was due to a leaky FET (at the A trigger input stage). The leaky FET was causing a DC offset at the input of the Trigger IC, beyond of what it can handle. After I located and repaired the guilty FET, I was able to even swap the ICs between A and B, and they proven to be interchangeable to the point of barely affecting the trigger calibration / adjustments... From the answers I got from the group back then, IIRC, the only difference between them is that the later one is made on a newer silicon process. They're equivalent and interchangeable. KRgrds, Fabio On Sun, Jul 22, 2018 at 03:59 AM, Jim Olson wrote:
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Re: Schematic/PCB KiCAD 5 is finally out and available
John Griessen
On 07/23/2018 10:44 AM, walter shawlee wrote:
Gentlemen,For people who like using linux and scripting and make files, (like chip designers), pcb-rnd is rapidly becoming a complete toolkit for making blind buried vias, defining groups of circuitry that move as one, searching for data in layout and extracting parasitics. The autorouter is soso, but there is another one and ways to use external ones also in the works. Schematics are possible to come from Kicad or gschem. You can import a netlist from eeschema and keep using eeschema, or switch to gschem if not a Kicad user already. pcb-rnd will not force upgrades on you ever -- older formats of files are going to be supported if anything changes. No upgrade treadmill. |
Re: 7603 specifically and general refurbishment procedures of older oscilloscopes
If it works with the 7L12 but not with known good regular plug-ins. More than likely don't have the right buttons pushed ( or a bad button) . Take a deep breath and check that you have the trigger selector set correctly for the channel your on and so forth.
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Beam finder works correct? Dave manuals@... On 7/23/2018 11:57 AM, johnasolecki@... wrote:
Hello everyone, --
Dave Manuals@... www.ArtekManuals.com |
7603 specifically and general refurbishment procedures of older oscilloscopes
Hello everyone,
I recently acquired a 7603 with 7L12 SA. I got the pair to use the 7L12 with my 7904A but I really like the large screen of the 7603. So I'm planning to use the '03 for audio work. The '03 seems to work when the 7L12 is installed but I can't get any kind of trace (except for readouts) when I use any of my 7000 series plug ins. I can't say I've tried every permutation but I've tried installing a 7A19, a 7A22, 7A26 in conjunction with a 7B92, 7B92A, 7B80 and a 7B85 with the "A" plug ins in the center & left slot and the "B" in the right with no joy. Because of this problem I'll be opening up the 7603; if anyone has any specific suggestions on where to look I'd be grateful but otherwise are there any common procedures for the overhaul of an older scope? I have quite a bit of experience rebuilding older amplifiers and radios but I bought my 7904A refurbished, I have no experience on older Tek scopes. I thought I'd start by cleaning the plug in connectors and as many pots & switches as I could access. While open I will check voltages and have a good look at the caps. Do you automatically replace all electrolytic caps or just ones that are showing signs of ripple or leakage? A search of the files section implied that tantalum caps are usually reliable and do not require preventative replacement (other than obvious failures). Are there any other common issues that need to be looked at? Any other suggestions? This will take me a while to complete but in the meantime, thanks in advance for any help, John |
Re: OT: HP 70843B Error Performance Analyzer, 12 GHz BERT info needed
hi Ed,
I believe that I had seen free .pdf manuals for the HP 70843b Error Performance Analyzer at the Kurt manuals site: However, a small quick start manual is available at the Keysight: Also, someone on the EEVblog may have some info on it: An HP blurb about it: Cables: The DB-37 pin HP MSIB cables can simply be made with crimp-on flat ribbon cable connectors: Let me know, rick |
Schematic/PCB KiCAD 5 is finally out and available
walter shawlee
Gentlemen,
Schematic/PCB software 5.0 from KiCAD, the massively powerful, long awaited, auto-routing and multi-OS integrated package, with better libraries and 3D models is now on their site for download. Also available in many languages, see the localization support. and yes, *free*, funded by CERN. this is a great public milestone, and very useful for guys like me that are not on Windows, as it runs on Ubuntu and many other LInux platforms (Debian, Mint, Suse and more) as well as Apple and Windows. This software is why several wildly over-priced commercial packages have had huge discounts recently, the days of the abusively over-priced $5K PCB CAD seat are running out. Eagle guys can import designs directly. It now also links to Ngspice. see: * for all the details. This is a great moment for designers that have not had a good tool that runs outside of windows, or one they could afford for personal use. all the best, walter -- Walter Shawlee 2 Sphere Research Corp. 3394 Sunnyside Rd. West Kelowna, BC, V1Z 2V4 CANADA Phone: +1 (250-769-1834 -:- We're all in one boat, no matter how it looks to you. (WS2) All you need is love. (John Lennon) But, that doesn't mean other things don't come in handy. (WS2) |
Re: Tek bits
Is there a complete inventory list?
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On July 23, 2018 7:52:01 AM "Andre de guerin via Groups.Io" <testing_h@...> wrote:
Hi, in my shed I have a lot of Tek bits including very hard-to-find long pots.have a few flybacks but not sure what state they are in. |
Re: Tektronix DM5010 NiCa 2.4V battery replacement
Hi everyone,
Ok, I've created a photo album ("DM5010 NiCad battery replacement info") with the battery schematic part and spec of the CMOS RAM. According to the DM5010 manual, the battery is to be replaced every 2 years. Procedure is to let the DM5010 running 24h for the battery to fully charge, and then do the calibration. The CMOS RAM (U1220) that is battery backed, is a HMI-6562-9 (Harris). According to the specification, the data retention supply current is 10uA max. For a 110mAH, that would be (110 / .01) = 11000 hours (458 days) for full discharge? At least, the battery should handle a month or two, I guess? Correct me if I'm wrong. Also, according to the schematic, we have a current limit of around 24mA (R1135 limiter resistor at 100R for around 2.3-2.4V) for the trickle charger. But the trickle charge would be quite high as R1131 is only 100R. Let's say BT1121 is 2.4V and CR1133 cathode is 5V, that would be around 24mA. Even for the original battery spec'ed at 150mA, trickle charge should be C/10 = 15mA. My planned replacement battery is spec'ed at 4mA for trickle charge, should I replace R1131 by a 680R resistor? This would give around 3.5mA max. Thank you for your comments. Best regards, |
Re: Dead 7603
I figured as much.?
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Thanks, Craig. Sent from my Verizon, Samsung Galaxy smartphone -------- Original message --------From: Craig Sawyers <c.sawyers@...> Date: 7/21/18 11:43 PM (GMT-08:00) To: [email protected] Subject: Re: [TekScopes] Dead 7603
BTW, I did try a 7A22, a 7A26, and a 7B85 in the plug-in slots last night.? Readout was a bitSince the 7B80/85 use +5V it is not surprising that they don't work properly if your 5V is screwy. Craig |
Re: 7603 Calibration Plug In Question
It is possible when you use the rigid extender. The signal coax cables in the extender can be disconnected and in their place external coax cables to another scope's input can be connected, all BNC and to be terminated into 50R. Even better would be the special signals pickoff calibration fixture between the -02 and the extender.
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Albert On Sun, Jul 22, 2018 at 04:20 PM, Harvey White wrote:
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Re: Tektronix DM5010 NiCa 2.4V battery replacement
On Sun, 22 Jul 2018 08:40:54 +0100, you wrote:
My (limited) understanding is that NiMH cells really don't like more than C/20 -As I remember it, NiCd cells can be left on trickle charge indefinitely, NiMh cells do require a lower trickle charge current. NiMh charging is intended to be C/4, C/2, or C (depending on the cell), but that is for a limited time with end of charge detection (either delta V, or temperature rise) with failsafe timers, etc. Look up the TI BQ series for examples of chargers. So for NiMh the trickle charge is a very low rate. The actual rating in MAH is dependent on age, manufacturer, etc. Chinese MAH, like the motors rated in Chinese horses on their lathes and mills, tend to be a bit smaller than we think. I did find some Raytheon 2400 MAH NiMh cells that measured just about 2400 MAH. Harvey
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Re: 7603 Calibration Plug In Question
On Sun, 22 Jul 2018 10:04:16 +0100, you wrote:
Thanks Adrian. What I was wondering was whether it could be externallyNo, the idea is to plug it in, in place of either a vertical or horizontal plugin, and it provides standardized signals to the mainframe itself, allowing you to adjust two scopes to the same gain. It also has risetime, linearity, and bandwidth signals. That one has the highest bandwidth, and is suitable for the 7104 scope (1 Ghz analog bandwidth). Harvey
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