#184 

Excellent video. Glad I found it even nine years later. One thing that might be worth adding is that it's usually good to let the scope warm up for 20-30 minutes before performing the calibration.

Nice! You gave me the courage to try to adjust my 44 year old 25MHz oscilloscope. The lines are beginning to oscillate in intensity and both X and Y axis amplitudes are off by 1cm. It was last calibrated in 30/01-85 and was due next 30/01-86 which is three months before i was born. Funny :)

Such a good (and useful) video...I really appreciate the way you explain the steps you take. Presentation is so clear and informative. Thanks so much!!

Very clear and instructive as always. A process I'd never previously considered to be so involved, if indeed I considered it at all. Thank you.

Awesome video, thanks Alan! I gotta say, what a lovely scope that is. Nice sharp trace, very clean and organized controls, what a beauty!

Finally a guy who talks electronics, grate set of videos that i have seen so far, keep up the good work.

This video was a great class for those looking for such important technical information! Thank you very much for recording your work; because that helped me a lot. Be able to see; how to make. Simply amazing!

Great video, very knowledgeable and concise information. Helps understanding about calibration and adjustments that can be made.

Beautiful work , i didn't realise the steps were so many in a simple scope. Also , what a great educational process building such a scope would be .

I like this video, watching every adjustment come back in gives me the feeling that all is right with the world... :)

Another great tutorial video, Alan. Many thanks, it gave me the confidence to attempt a rudimentary calibration on a Tek 7403N I just managed to resuscitate and save from the scrap yard!! :-)

Great instructional video - thanks so much for taking the time and sharing your knowledge.

This is a brilliant video, thank you. I just purchased a GoldStar OS-7020 scope, and I will go through exactly this process (as soon as I can track down an elusive service manual)

Even though I have a different scope, this was a helpful intro to help me understand what I'm looking for when calibrating my own.

Thanks Alan for another Great Video!!

W2aew - your content is top notch. I really don't understand why the RU-vid algorithms constantly push celebrity court cases or how much can you eat challenges when this sort of subject matter is all I ever watch!

Really nice video, very well put together!

That was very informative. Thank you for creating the video.

Very good info. Why would anyone dislike this? Thanks Alan.

Enjoyed your calibrate video and it pointed out how I do, indeed, have to find the instruction manual for my NRI model 2500 scope. Many of your other videos, however, are also helping me out to learn how to operate the scope.

Alan, Superb video as always. This is a perfect warm up for calibrating a couple of Heathkit scopes, an IO-4510 and IO-4550 as well as an Elenco 1325. All together, I spent $65 for the three of them a various ham fests. These scopes will be good practice because four Tek 7000 mainframes and about twenty plug-ins will follow. Thanks for the great work. Thanks, Paul, W1SEX

A great job as usual!

Thank you for this video, its just a hobby for me and you helped a lot.

Another great vid Alan. Many of have heard of cal'ing a scope; I for one didn't know how involved it was... Thanks!

I have watched this over 20 times...such a brilliant informative how to Most 20 -25mhz CRT oscilloscopes look they are the Pintek chassis, I have seen, my Telinstruments, Sony, even the Hitachi V20, look the same, they all seem to havea common REAR panel , connectors The Heath 4552 service manual is easily available on the Web, unfortunately my Telinstruments TI5252 was not.

otro gran video de mister muy instructivo y motivacional muchas gracias

Excellent lesson all around! Looks like it was fun to kick back and tweak "ol' betsy"! Actually, this procedure is up next after a Eico 460 rebuild!

Nice information, like allways, with sound advise, brings me back to my first serious scope cal, a Tek 465. I got it right but it took a lot off time (like 15 hours or so) and I learned a lot from it, and for most that you first have to check if you understand every step and have all the gear needed. Missing one instrument can screw up the whole operation. I really learned that when I calibrated a 1ns pulse generator with a 150 MHz scope. It looked perfect until I got a 1GHz scope and had to do it all over again. You often need better testgear as the gear you are adjusting or repairing. Some tips for your viewers if you do not mind: Do not think to light about calibration and adjustments of test gear, it is very easy to make it (much) worse. A tip I learned long ago from an experienced meterologist, is to mark the settings of adjustable components before you adjust them, so that if you screw up, you can get it back to its old state. A picture will help too. What I sometimes do is making a few high res pictures and marking all adjustment points with their name/number and value and in more complex steps the number/paragraph that step has in the manual. That can speed up things a lot and forces you to read and understand every step in the process before you start. Do not do partial calibrations unless you really know what you are doing and not because you do not understand a step in the process. It is very easy to make it worse. Back then it was a hobby (it still is) . Nowadays I make my living from repairing test-instruments and calibration gear. I do no calibrations (not my idea of fun ;-) ) but depending on the work I did, I sometimes have to calibrate it, or at least check it after repair.

Good video. Nice work.

Great video! Thank you.

Top notch! All my thumbs up!

I have the same scope branded with the Elenco name. Came with my NRI home study course in the early 90’s. Still use it. Works great. Maybe I’ll go through it and touch it up a bit.

Very good video, thanks!

This is excellent! I wish I could find the equivalent calibration procedure for my Sencore SC3100. I'm not sure those instructions exist.

You forgot to mention maintaining the correct tongue angle when making adjustments :p

Thank you. I am in the midst of an HP Agilent 1740A mega repair / refurb and have all this to come. Still chasing vertical jitter in this one. The gremlin has hidden itself well in this one!

Job well done!

Probably important to emphasize is that it needs time to warm up and settle before you make calibration adjustments. But that goes for use as well.

Another Great Video ... Thankyou .

Nice work. That Heath scope looks almost new. Aside, the quality of the documentation are pretty rare to find in modern gear. It does serve to warn others looking to get an analog scope of unknown status over eBay that getting the parts replaced in one thing, adjusting it to factory performance is another.

the first job I had on a bench, was equipped with one of these scopes. I realize they were rebranded under different names sometimes. But my goodness just Imagine how many of these scopes were sold to ametuers, hobbyist, schools etc. And how many good techs were self taught using these. Back in the day a 20 or 25 Mhz dual trace scope was the entry level scope, And extremely useful even to this day..I really enjoyed watching you calibrate this old girl...Sorta like watching someone do a tune up on a 57 Belair. .......lol....N8QZH

The 60mhz scope I just bought used is a bk precision 2160a, has almost identical controls on front panel, including component test on bottom row. Bk did not provide much for calibration in their manual. I have found that hk so-4552 manual with the specific adjustments you done. I’m not going to do any, but may check references from the manual if I find problems down the road. Thanks for sharing!

very nice video

Just a thought - since I work on stereo equipment for a living, I think I would do the ch. 2 vertical sensitivity adjustment by overlaying it over ch.1 (after it has been adjusted) and adjusting so that the two channels match as closely as possible. Just my .02...

Alan thx for sharing. As for the transient response adjustment, the picture in the manual shows ringing and you even commented about the ringing. I like what you ended up with, a nice square wave with no ringing. I'm with you, if I could've adjusted it so that I didn't get ringing but got the squarest wave I could I would've too. I wonder why they suggested adjusting the transient response so that ringing was present. By the book a little bit of ringing does give the widest bandwidth before falloff like a Chebyshev filter. However, the downside is the time domain suffers. I still like your solution. Again, thx for sharing.

Very good.

Excellent

Thanks for you video

Excellent. Thank you. Why are “experts” unwilling to try things like this?

Congrats! And liked! I have the same exact oscilloscope but as a brand it writes MiteK mk4300..im so happy that the only complete oscilloscope calibration on RU-vid is on my oscilloscope... Must say that the insides look completely the same as well. just the operation led is red on mine, not green but when possible I will change it because it's annoying and looks awkward

Hi, I like your video, very easy to follow. I've got a bit of a problem, wondering if you could help. I picked up the same scope off an auction, but there's an electrical problem I can't quite track down. Is it possible to get a scan of the electrical diagram that came with it? Mine came with no manuals. I'd really appreciate it.

I just bought a Heath IO-4550 for hobby use and audio work. It's not coming with manuals, had to buy the assembly and user manual separately. I would think a quick inspection of the power supply electrolytics will be my first step before attempting calibration. Thanks for the video.

thanks enjoyed this very much

If your videos get the merit that they deserve I would suggest that your introduction salute the viewers from the 22nd century and after ;^)

Enjoyed your video Alan! It does look strange to see you calibrating a unit that is less than 1 Gig!! 73's , Gary Grove

Very tinely since I just picked up a Tek 2225. I haven't played around much with it yet to see if it's in need of calibrating.

Thanks for the informative video. What did you use as you signal sources? I have a Tektronix 465, like you too. I wish you had done that scope, but I'm not complaining! It's nice to see what you had to do, so I'm aware of what is coming down the road for me and my oscilloscopes.

Good video Alan, you make it look easy. Do you know where I might find service manuals for my two Kikusui oscilloscopes. I have a COS5040 and a COS5100. They both work great, but could stand to be calibrated.

Thanks for the wonderful video. Although I have both digital and analog scopes, I really like the analog for the real time stuff. Is there an alternative to the Time Mark generator for calibration?

Great video, always looking forward to your next one. 73 VE3BHM Larry

Great video, thanks! I just picked up a used Tek analog scope I'm going to try to repair/calibrate. This is my first time working with with a device with high CRT voltages. Where did you get that insulated screwdriver? I'm having trouble finding something spec'ed above 1kV, let alone the voltages in the scope (14kV).

Alan, this is FANTASTIC. About the best I've seen in the way of calibration, you sound like you might be a teacher. I worked with these scopes for about 25 years (DEC) and have the exact one you use in this video. Do you know where I can get the Service Manual? I've looked, but it's pretty hard to find. Thank you again for such a good and professional video.

Hi Alan, thanks for the video and the very clear explanations. I'm somewhat new to the O-scope world and certainly new to scope calibration. I would love to have a generator like a 3252 but it's out of my budget at the moment. Are there less expensive (

Thanks for this great video! Very helpful. Was wondering about the 50ohm terminator, why was that used? Didn’t see where that was required in the video shots of the manual you were using. Is it because you are not using a probe but directly connecting to the waveform generator?

Hi Alan. What is the name of the adjust made at 16:02 where you adjust the wave to zero on the left side of screen? I have a hp1740A in need of this adjustment. My listening in english isn't so good but, you said trigger offset?

Very informative video.. What brand and model of HV robe is that? I'm looking for one currently.. thanks.

Hello Alan, Thanks for another great video. Where can I get these small and nice BNC cables you are using? Are they sold like this or did you make them yourself? What kind of cable is it? It is so nice and thin. Thanks

Hello , Been watching your videos on oscilloscopes. I just got a Sperry 620C . It's in excellent condition , but I have an issue with the vertical position . It won't come down to center on either channel . It's all towards the top and off the screen . Any thoughts on what to look at . Any help would be greatly appreciated . Thanks

Another real master class, Alan ! By the way, I'd like to thank you for the spectacular knowledge that you spread through your videos ! Do you have any reference material / video about Delay Time / Dual Time Base oscilloscope calibration, please ? Merry Chrismas & Happy New Year ! Wish you all success, heath, peace, happiness and the best greetings from Brazil !... ^_^

Great video just picked up this scope, question where did you find the service manual.

What signal source did u used to "cal" bandwidth, response time and time base?

Hello sir, I have watched a few of your scope videos and they are very helpful. I appreciate them. I have been playing with Tektronix 465 units and now have 3 of them. I was able to get the first 2 going and I have a question as I dig into the third regarding the use of an old Triplett 630 VOM to measure the HV supply. It has a 6000 volt range but I was wondering if it has too low of an input impedance to measure the -2450 on the Tek 465 (doing this measurement hands off of course). I understand the HV probe would be the better and safer thing to use here ( I do not have). I was just wondering your thoughts if you care to share. Thank you , Jim

Thanx for this one, as i now know that i do not have to open my "new" "Vuko VKS220-16" scope to rotate the CRT for an all flat trace, as the little trimpot, you´re revering to at 06:40 has only "TR" written on the silkscreen of that vuko, and it´s just next to intensity, therefore i thought this is to trim the intensity. Now i know better. As that "TR" is AKA trace rotation. Thanx a lot for this, rather tiny but very useful, hint, as it prevents me to work that scope CRT :)

I'm jealous. I am in the middle of repairing & calibrating my EMG-4656, 25MHz Hungarian scope (tek copy I think) from the end of the 1970's. Let me tell you, your is a hundred times more well built than this piece of mess. Lots of wires, connectors, most of the board is hard to access, darn hard to disassemble... Fortunately, I have a digital copy of the original manual, including the full schematics and calibration instructions.Sadly, the latter are very inaccurate, especially on how to locate the adjustment controls - referring to the wrong picture, etc. Sometimes it's straight wrong, as it mentions to adjust pots in a compleatly unrelated circuit, which will be adjusted again in the relevant section... Now I spent a week or so writing down every instruction again with the actual positions of the controls, sometimes traced back from schematic or board layouts, and just figured that I somehow broke the HVPSU while searching for the controls in there. No discharge resistors on any of the caps, so I've put the whole thing aside (also, I'll have an exam in a week), before I dare to open it again... I also lack some of the necessary equipment to properly check everything, but I have most of the stuff needed to actually adjust things. I won't ever touch anything in the HVPSU while it's on, for example. I am still pretty sure I can do with the stuff I have, as seeing the mechanical build, this is one of the pieces of eastern tech that is a miracle to work, but unbreakable.

I just need to know what nomenclature HP uses for trigger offset.

I have the Pintek brand of basically the same scope with delay sweep. I have a slightly bent trace from left to right of screen(not the rotation), I think I caused it by not having my probe set at 10x, when I was measuring a higher voltage. I was wondering, is there any adjustment for this or did I damage the plates in the tube?

Could you help me, what instruments are needs to calibrate a Tektronix 2465 ?

Love your channel..is there any way of making this procedure less dangerous? eg an isolation transformer etc? or are the CRO votages , unavoidable just way too high? Thanks in advance.

I have the same scope with the pintek brand name. I was wondering if there was a calibration for the cal lug?

Hello Alan. My name is Alexander R2DHL. I have got an old Tek 2445b and this is my favourite scope. About a month ago an error appeared: test 4-11 (calibration constant checksum) and everything pointed on a nvram chip NEC D4364C-12LL fault. So I have replaced it with the UT6264CPCL-70LL chip (it has more memory and a litle bit faster). The battery was made in 1988 and there was 3.6 volts on it but I have made a decision to replace it too. Now I need to calibrate my scope. The calibration manual that I have found on internet is not easy to understand because I am doing that for the first time. 2445b is a pretty common scope but I could not find any video instructions for the calibration procedure. I will be very appreciated if you will help me with my problem.

i did find your video very interested , . i do have an oscilloscope in my position the DM64 Analogue storage oscilloscope i have not a clue how to get it working for so long . i do have all manual seen your video i am going to have a go

this scope has been also sold as teklab osc-25 and mine has a issue where the up/down position is faulty on both channels and has to be set fully to one end to show on the screen so need to do checks on where the fault is at

Is the ripple at 11:38 normal, when you use the vertical magnification? I also get it on a second-hand analog oscilloscope that I bought.

Hi Alan, again I need your advice. The scope I was restoring looks great using your suggestions, of Windex and alcohol. The potentiometers need cleaning. The scope is a Tektronix 422, some sites say don't use contact cleaner but replace them, that would be cost prohibitive, what is your suggestion. Thanks Larry

Thank you for yet again for an interesting video.. but sadly I wont under take doing mine - High voltage calibration is not for me.. good advice noted.

I have the problem at 18:51 in the video..where the vertical pips are not in alignment the further you get from left to right...I can find no adjustment in this old scope (Hitachi V-302)...what is the pot for this adjustment called in your scope..Thanks for all the fine work you do...I can tho turn the SWP VAR to get them to line up...

Just gotten a Hitachi V-209 20MHz, and I can’t seem to find the calibration manual/instructions for it. The V-212 is also A 20MHz scope and there’s one for it, but coming up dry on the V-209 any help?

thx

Hi , i could really use your advise, my channel 1 is receiving a 1khz signal but my vertical position control will not bring the trace high enough to centre the trace.. channel 2 works fine.. it is a a Telinstruments TI 5252 25MHZ scope, . The correct waveform is there but is hanging way below the bottom of the scrren..very frustrating. Cheers

Hi, is there any procedure for checking the calibration status of the analog oscilloscope, without disassembling it ?

At 9:35..which pot, or should I say what is the adjustments pot name being made to make it stay the same when a and b are in the ADD mode..???

HOLA AMIGO...TENGO UN PINTEK PS1000 ..EL PROBLEMA QUE TENGO ES QUE PERDI UNOS RESISTORES DE LA PARTE DE ALTO VOLTAGE QUE ALIMENTA LA GRILLA Y CATODO..TENDRIAS EL CIRCUITO? SALUDOS ..

My scope display is not blue on my Heath 4552?What seems to be the problem?

18:30 what is that "time mark" on the screen? Just a short pulse?

Best of others

Hi Alan. I have a 20MHz GW-Instek GOS-620 scope, but unable to find a calibration manual for it. I saw on Tek's website that they perform such calibration, so I assume they have the manuals. I was wondering if maybe you have one, or can get one somehow? Would be of great help, so I can finally calibrate my oscilloscope. Thank you.

Do you have digital copy of that scope? I have an old oscilloscope, not same brand, but has very similar button layout.

I have the exzact same Heath 4552 oscilloscope. Where would I get the service manual for it?

hello, im scare to measure the -2kv because i dont have that HV probe, what can i use? (saw diy HV probe but i want to be sure before using that). I have the same scope, i turned on and after 20 seconds hear a POP and saw a light (an arc maybe?). I turn it off. Im recoleting info to start troubleshoot

Is it normal for a waveform to change amplitude when turning the position knob or is that an indication of something being broken?