National Oscilloscope VP-5263A Manual Required - Page 1
Forum section: electronics / repair

author: Matchless
author_rank: Regular Contributor
timestamp: October 26, 2014, 11:44:37 am
content: Hi,I have discovered and old National VP-5263A that is for sale and would like to buy it and repair or refurbish it, but cannot find any specifications or manual or this model. The owner has had in storage for many years and it did work before storing it. But it will need calibration at least.Can anyone help or advise?Much appreciated.

author: tautech
author_rank: Super Contributor
timestamp: October 26, 2014, 07:00:42 pm
content: Maybe it is a "re-badge"?Power it up slowly to let the E-caps reform after lying idle for so long.Incandesent light bulb in series with the mains should do the trick.I would allow a good 1/2 an hour.

author: Matchless
author_rank: Regular Contributor
timestamp: October 26, 2014, 07:21:15 pm
content: Thanks for the tip!The picture looks very much like the VP 5260A minus 2 switches and I did see a 1974 add for the same one in a old electronics monthly article via Google.I will see if the seller still has it this week.

author: SeanB
author_rank: Super Contributor
timestamp: October 26, 2014, 07:46:33 pm
content: Gumtree in George? Yes I second the warm it up gently with a 60W light bulb for an hour then try it out to see just how many of those old Matsushita caps have dried out.

author: Matchless
author_rank: Regular Contributor
timestamp: October 27, 2014, 08:33:22 pm
content: SeanB,Yes! Small world! Hoping to pick up the scope this week and give it an internal examination!Hopefully someone has a long forgotten manual laying around!

author: rstoer
author_rank: Regular Contributor
timestamp: October 28, 2014, 02:46:25 am
content: National was the brand name Matsushita Electric Industrial used on their products everywhere but the US, where they used Panasonic. Sometime in the 1970's they replaced the National brand with Panasonic worldwide. Later still they changed their corporate name to Panasonic.Therefore you might find a service manual under the Panasonic name for the same model. I've also heard that some of Panasonic's test equipment was sourced from Leader. I don't know if that's true but you might see if any vintage Leader scopes are identical to yours. Good luck.

author: Matchless
author_rank: Regular Contributor
timestamp: October 28, 2014, 09:20:57 am
content: Thanks for the info.Yes I have tried searching for National, Matsushita, Panasonic, VP-5263A and any sort of combination that I could think of. I did find some references, on someDutch, German, Italian and Japanese sites, but no useful detail.If it was branded differently in the USA due to the National name brand clash, it most likely had a different model number as well, but would have the same physical appearance I think. I have attached a picture for reference.I did find the scope advertised in an old Italian Electronic periodical of 1974 though.I did however also find a complete manual for the National VP-5260A which looks very similar but has an extra sweep control switch.So I am still looking for a 1974 (approximate) National VP-5263A manual and/or schematic unfortunately.Hopefully someone can shed some light on this!

author: Matchless
author_rank: Regular Contributor
timestamp: October 29, 2014, 08:14:22 pm
content: I finally have the National VP-5263A oscilloscope. The first thing I noticed is that it does not have a mains voltage selector and is labelled 230V AC. Opened it up, cleaned out as best I could as well as removed all the DNA on the outside and powered her up. Replaced the red on neon light and did some basic tests. So far all is well.I think I will need the manual to calibrate her properly.I have attached some pictures of the insides.

author: Matchless
author_rank: Regular Contributor
timestamp: November 03, 2014, 06:06:12 pm
content: I have found and advertisement for the National VP-5263A Oscilloscope in a 1974 Dutch electronics catalog!It has some specs included. I wonder what the price would be in todays money?

author: oldway
author_rank: Super Contributor
timestamp: November 03, 2014, 06:31:54 pm
content: You are kidding ?Calibrate such a low end scope ?If it is working, let it rest in peace...

author: SeanB
author_rank: Super Contributor
timestamp: November 03, 2014, 06:58:26 pm
content: Cal is easy, if it is within 10% ar all voltage ranges, and within 5% on all speeds it is working.

author: oldway
author_rank: Super Contributor
timestamp: November 03, 2014, 07:23:28 pm
content: Quote from: SeanB on November 03, 2014, 06:58:26 pm20% is already good enough ....it is a low end, low quality oscilloscope.

author: SeanB
author_rank: Super Contributor
timestamp: November 03, 2014, 07:33:01 pm
content: It's National, 20% was not good, you generally had 5% on timebase speeds and the CRT vertical was within 5% at full deflection. Depending on the tube you would have non linearity of some amount, but it was a lot better than a TV set where 20% was good. It may only be a 2MHz unit, but they are quite good.

author: Matchless
author_rank: Regular Contributor
timestamp: November 03, 2014, 07:47:02 pm
content: Quote from: oldway on November 03, 2014, 06:31:54 pmOh no! Here I was thinking a 1974 10MHz scope was a bit more than low level!Actually it's in a very good condition except for a few minor outside blemishes and I would like to know that it is accurately calibrated though!I have heard that it is/was just as robust and reliable as the National TV's and car radios from that era!

author: oldway
author_rank: Super Contributor
timestamp: November 03, 2014, 08:07:22 pm
content: Have a look on a Rigol DS1054Z and you will understand what I mean....There have always been two product lines for analog oscilloscopes- scopes of 10 and 20 MHz bandwidth for use in TV repair or hobby.- scopes of 100 MHz or more for professional use.(The best example is the Tektronix 465.)Already in 1975, there was a huge gap between them, both in technology and quality.National has never been a reputed name in the field of oscilloscopes.There is no hope to make precision measurements with a device that originally was not already planned for this, and that is now 40 years old.

author: Matchless
author_rank: Regular Contributor
timestamp: November 03, 2014, 09:22:01 pm
content: Hi Mr oldway,That was just my tongue in the cheek reply!I used to have Leader and Tektronix scopes at work and they were definitely quality, but very expensive!At this time its just part of a hobby of mine. I definitely do not need nor can I afford the latest Maybach model. The Datsun 1200 level scope, plus the nostalgia of having one is good enough for me! I have a USB DSO to fall back on if needed, also low level unfortunately!Thanks for your reply it is well appreciated.I am still hoping that someone will come up with a manual and/or schematics for this model.

author: Matchless
author_rank: Regular Contributor
timestamp: November 09, 2014, 06:56:24 pm
content: To date a manual for this oscilloscope is still elusive unfortunately.I have used the National VP-5260A manual which has a lot of similarities to the VP-5263A albeit with some extra facilities not found on the lower level 5263.I have managed to adjust the DC balance and Ch1 and Ch2 gain by following the 5260 manual and have noticed that some of the internal pots have a similar numbers.It should be possible to do quite a bit of calibration, if not all, using the manual for the VP-5260A and some common sense.Even the schematics have some similarities that could help with fault finding if needed.

author: CharlieD
author_rank: Contributor
timestamp: January 09, 2024, 09:02:00 pm
content: Quote from: Matchless on October 28, 2014, 09:20:57 amHello, I need the service manual for that exact model, there is a link in the Forum, but looks like is down, if you could upload the manual in this thread it would be great.

author: Matchless
author_rank: Regular Contributor
timestamp: January 10, 2024, 07:15:47 am
content: I have not been on this forum for a long time! The file is 33 meg, will upload if you can give me a link

author: TERRA Operative
author_rank: Super Contributor
timestamp: January 10, 2024, 12:38:06 pm
content: You can upload it here if you like:https://groups.io/g/Japanese-Test-Equipment/files