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Re: Tek 2465B-CT scope
Thanks for the information!
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On Tue, Aug 13, 2019 at 4:07 PM Chuck Harris <cfharris@...> wrote:
Last CT problem I fixed was due to a bad trigger hybrid |
Full 7503 manual online anywhere?
My second 7503, which I thought was completely dead, is actually showing signs of life.? It has a P11 CRT, which is fairly dim at max intensity, and activity can only be seen with the beam finder pulled out.? Mechanically, the scope looks like it had a bad day at some point in it's life...
Are the schematics anywhere online for this scope?? All the manuals I've found so far are copies of the 96 page version, which is missing everything after the description of the readout system. -Dave |
Re: non-gumming oil
Ultrasonic cleaning is a very good way to get the crud out of sintered bearings. Now that analog turtables and tape recorders are being sought and used again, some AudioPhool boutiques gush about their multi-step ultrasonic cleaning and re-oiling process for motors. Many of those same boutiques are eager to find and use classic Tektronix scopes and Hewlett-Packard signal generators and distortion analyzers. They are also the ones who search for 5XX models at hamfests, take out all of the tubes and the power transformer(s), and throw the rest in the dumpster.
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Bruce Gentry, KA2IVY On 8/13/19 7:13 PM, Ken Eckert wrote:
I wonder if ultrasonic cleaning would help before relubricating, assuming |
Re: non-gumming oil
I wonder if ultrasonic cleaning would help before relubricating, assuming
the bearing can be removed..... On Tuesday, August 13, 2019, Bob Albert via Groups.Io <bob91343= [email protected]> wrote: One can indeed relubricate a sintered 'lifetime' bearing. I have been |
Re: General Radio 874 Connector, inner conductor "bendies"
On Aug 13, 2019, at 08:11, Dennis Tillman W7PF <dennis@...> wrote: |
Re: Is an early 7A26 a keeper?
On Aug 13, 2019, at 00:24, Dennis Tillman W7PF <dennis@...> wrote:
Still have a link? (I know the fundamentals, but a ready-to-use recipe would be great.) Gr¨¹?e, Carsten |
Re: non-gumming oil
Bob Albert
One can indeed relubricate a sintered 'lifetime' bearing. I have been successful doing it.
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The preferred method, time intensive, is to remove the bearing and soak it in oil for a day or two.? It will eventually take in enough oil to allow it to operate for a very long time. Another, less effective, method is to drizzle oil on the bearing repeatedly, like three times a day at first and then once a day.? When it doesn't dry up any more, it should be good to go. Once you reinstall them, use urdinary lubricating procedure to make sure they are going well.? After having done that, you can leave them alone. However, if they have been run dry for too long, the pores may have closed up and won't take on fresh oil.? When a bearing starts to make noise, it's wise to take it out of service.? And ignore the 'lifetime' appelation; oil them now and then. On Tuesday, August 13, 2019, 02:22:15 PM PDT, Richard Knoppow <dickburk@...> wrote:
? ? I am not so sure about what additives there are in engine oil. One can get good quality SAE 20 machine oil at many hardware stores. 3-in-one puts it up in a blue can (red can is something else). Also as Kano Microil, very highly refined petroleum based oil, wax free, and does not gum. Most of these blower bearings are so called "life time lubricated" meaning it works until it doesn't. They are made from sintered bronze with oil held in the spongy metal. You can't really re-lubricate them in any easy way but they will hold oil for a reasonable time. ? ? Hewlett-Packard used blowers with a rubber seal at one end. They could be re-lubricated using a syringe to poke through the seal and inject some oil. I have no idea if the Tek blowers are similar.? Unfortunately, once the bearings run dry they will become galled and run rough despite having new lubricant. ? ? I agree with you that mixing silicon oil or grease with petroleum lubricant is not a good idea. On 8/13/2019 2:03 PM, Chuck Harris wrote: Why?-- Richard Knoppow dickburk@... WB6KBL |
Re: non-gumming oil
I am not so sure about what additives there are in engine oil. One can get good quality SAE 20 machine oil at many hardware stores. 3-in-one puts it up in a blue can (red can is something else). Also as Kano Microil, very highly refined petroleum based oil, wax free, and does not gum. Most of these blower bearings are so called "life time lubricated" meaning it works until it doesn't. They are made from sintered bronze with oil held in the spongy metal. You can't really re-lubricate them in any easy way but they will hold oil for a reasonable time.
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Hewlett-Packard used blowers with a rubber seal at one end. They could be re-lubricated using a syringe to poke through the seal and inject some oil. I have no idea if the Tek blowers are similar. Unfortunately, once the bearings run dry they will become galled and run rough despite having new lubricant. I agree with you that mixing silicon oil or grease with petroleum lubricant is not a good idea. On 8/13/2019 2:03 PM, Chuck Harris wrote:
Why? --
Richard Knoppow dickburk@... WB6KBL |
Re: Tek 2465B-CT scope
Chuck Harris
Last CT problem I fixed was due to a bad trigger hybrid
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in the scope. The trigger hybrid has to be extra especially good for the CT option to work. It is the beginning and the end of all counter timer operations. The weakest link, as it were. -Chuck Harris Dwayne Reid wrote: Good day to all. |
Re: non-gumming oil (was: 547 Fan lubrication) OT
Chuck Harris
Why?
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Silicone oil isn't miscible with the original oil, and you are not going to make the motor become maintenance free, no matter what you do with oils. Just give it some motor oil, thin like SAE5 or 10 is fine. Detergent isn't like the stuff you wash your clothes in, it will not cause any problems, in spite of its suggestive name. The synthetic doesn't oxidize as quickly as the old oil did, but then any modern oil is much better in that regard. The last time anyone lubed your scope fan was likely 40 years ago and yet, it still works. Give it a couple of drops of oil, and move on... be happy! -Chuck Harris Stephen Hanselman wrote: I've read some of the answers and wanted to add my two cents. We use marvel |
Re: Is an early 7A26 a keeper?
John
In reply to Dennis's comment about the 1/2 scale reading. I checked the output from the input stage going into U1350 on Channel 1 and it is the same on both channels so I don't think it is in the input switching. Anyway I am going to build up an extender and one day (see there it comes again, you know that one day that never seems to come around) we'll get stuck into it and figure out what is going wrong.
John Proctor VK2DLP |
Re: Is an early 7A26 a keeper?
Yes, I know that Someday very well! ;)Jim FordSent from my Verizon, Samsung Galaxy smartphone
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-------- Original message --------From: John <john.d@...> Date: 8/13/19 1:53 PM (GMT-08:00) To: [email protected] Subject: Re: [TekScopes] Is an early 7A26 a keeper? Folks, I am sorry that I seemed to hijack this posting but thanks for the information. I can see where a passive 50 ohm probe might have been useful in my current HP 8662A resurrection job. One place that was particularly troublesome was in one of the VCOs which was tuned by 10 parallel connected varacaps. It would oscillate sometimes and other times it was dead. When it did oscillate it would sometimes go free run with many spurs. I was going towards the JFET having gone slightly tropo but it was solved with a replacement module which came up at a good price. Someday I'll get back to it (you know that some day which never comes). Thanks for the input and I'll keep my eyes open for something like a P6056 or P6057. The problem is that most eBay sellers have lost the plot on pricing. Once again thanks for the advice.John ProctorVK2DLP
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Re: Is an early 7A26 a keeper?
John
Folks, I am sorry that I seemed to hijack this posting but thanks for the information. I can see where a passive 50 ohm probe might have been useful in my current HP 8662A resurrection job. One place that was particularly troublesome was in one of the VCOs which was tuned by 10 parallel connected varacaps. It would oscillate sometimes and other times it was dead. When it did oscillate it would sometimes go free run with many spurs. I was going towards the JFET having gone slightly tropo but it was solved with a replacement module which came up at a good price. Someday I'll get back to it (you know that some day which never comes). Thanks for the input and I'll keep my eyes open for something like a P6056 or P6057. The problem is that most eBay sellers have lost the plot on pricing. Once again thanks for the advice.
John Proctor VK2DLP |
Re: non-gumming oil
It is a good oil, comparable to the original. It will become rancid in time just as the original did, especially if there is moisture. It is also used in hydraulic elevators as the working oil and as general lube by those working in the craft. It is well refined mineral oil with few or no additives, but I think synthetics are far better. I had far better luck with synthetic is fan motors in elevators. I worked in the craft for over 30 years. Most oil distributors have it by the pail, one source for smaller quantities is to befriend an elevator or air conditioning technician. Most appliance supply dealers have it in small squeeze bottles for exorbitant prices. NEVER call an elevator company, or worst yet, a supervisor. Deal direct with a technician, a cup of coffee or a soda will get you all of the oil you are likely to use for some time!
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Bruce Gentry, KA2IVY IUEC Local 62, retired On 8/13/19 2:11 PM, Merchison Burke via Groups.Io wrote:
I was told by an air-conditioner technician that Turbine oil was recommended for use in the small fans used in air-conditioners, being that it is very light. |
Re: non-gumming oil (was: 547 Fan lubrication) OT
Years ago I got a can of Slick 50 One Lube. It was actually a pump dispensor,
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not an aresol, and I've use that for similar applications. It was a nice product, still have half the can. I see that they've "new and improved it" and removed teflon from the formula, so YMMV. I use MMO in my air tools, seems a bit thin for this application. Paul On Tue, Aug 13, 2019 at 10:43:10AM -0700, Stephen Hanselman wrote:
I've read some of the answers and wanted to add my two cents. We use marvel --
Paul Amaranth, GCIH | Manchester MI, USA Aurora Group of Michigan, LLC | Security, Systems & Software paul@... | Unix & Windows |
Re: non-gumming oil
I was told by an air-conditioner technician that Turbine oil was recommended for use in the small fans used in air-conditioners, being that it is very light.
Can anyone give an opinion about this oil? Merchison On 2019-Aug-13 1:43 PM, Stephen Hanselman wrote: I've read some of the answers and wanted to add my two cents. We use marvel --- This email has been checked for viruses by AVG. |
Tek 2465B-CT scope
Good day to all.
I recently acquired a Tek 2465BCT (GPIB option) that has some problems. The first problem is a diagnostic error on power-up: (I think) 06 02 This was displayed the first couple of times that I powered the scope up but hasn't happened since. Unfortunately, I assumed the error would always come up every time I powered the scope ON, so didn't take a picture of the screen. Oops. The second problem is that the sweep collapses / goes wonky for a second or two after several minutes of operation. Again - happened a couple of times but hasn't happened since. Third problem showed up this morning: CT TEST 84 FAIL 0C This time I did take a picture of the screen <grin>. I haven't done any other checking on this unit. Yet. I'm hoping that others more knowledgeable than myself can tell me what the potential issues are. I am assuming that the first error message relates to weak or dead battery for the calibration constants. I'll look at doing some of the work myself but rather than trying to fix major problems myself, I'm thinking of sending it off to someone to have them check it out, do any repairs necessary, replace all capacitors that are known to fail over time. I've used a fellow named Alexander Schonfeld in the past - he seems to do good work but I'm open to other suggestions for other people. Many thanks! dwayne -- Dwayne Reid <dwayner@...> Trinity Electronics Systems Ltd Edmonton, AB, CANADA 780-489-3199 voice 780-487-6397 fax 888-489-3199 Toll Free www.trinity-electronics.com Custom Electronics Design and Manufacturing |
Re: non-gumming oil (was: 547 Fan lubrication) OT
I've read some of the answers and wanted to add my two cents. We use marvel
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mystery oil which seems ok so far. I was thinking about using silicon based gun oil though steve -----Original Message-----
From: [email protected] <[email protected]> On Behalf Of John Griessen Sent: Tuesday, August 13, 2019 8:59 AM To: [email protected] Subject: [TekScopes] non-gumming oil (was: 547 Fan lubrication) OT On 8/13/19 10:30 AM, Chuck Harris wrote: I use mobil 1 5W30... because my car uses it, and I collect the dripsspeed. I took it apart to find the bearings all gummed up with sticky greasy old oil. I've washed it all out with an appropriate solvent and now need to relube it. Is there a recommended oil to use? I have various grades available ranging from 3-in-1 to heavy EP90. Do you think synthetic motor oil is as good as Kano Microil non gumming instrument oil? I'm getting low on that oil. |
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