Teardown - Hitachi V1065

[grumpydoc]

A first step might be to replace capacitors on the boards.  They might have aged badly.

I'm afraid it looks like physical damage to the CRT

[ulyanoff]

Thank you all. If the CRT tube has physical damage, then I think there is a vacuum loss and no trace is displayed on the screen. All secondary voltages from the power supply unit are checked and correspond to the circuit. After few days I will back with results.

[grumpydoc]

Thank you all. If the CRT tube has physical damage, then I think there is a vacuum loss and no trace is displayed on the screen.

Not always.

The CRT has a number of internal structures made of glass which can be damaged by mechanical shock, as well as the horizontal and vertical deflection plates.

Eg see this thread https://www.eevblog.com/forum/repair/tek-2211-crt-weirdness/ for a 'scope with similar display problems.

[ulyanoff]

A bit sad message, most likely now I'm looking for any version of the CRT Matsushita 150DGB31. How do you think how realistic it is to find? Also additional , maybe someone needs an entire oscilloscope or some parts or block from it. You can consider the option.

[Moonbase]

Seems this thread’ll never die. Ever. :-)

Thanks to all for the teardown, photos and especially the search for S1603!

Unbelieveable how time flies … I’m the proud owner of a VC-1065C for about 30 years now, and guess what: After having neglected my beauty for about 10 years now, I took it into service again and promptly S1603 (the selector switch) stuck—in SINGLE mode! Aargh!

I’m a sentimental guy. Guess I want to spend a few more years with this beaut old lady … So, please, anyone got a spare with the original paddle? Or do I have to try DigiKey’s 360-3390-ND (A28KB-BH)?

It wasn’t clear from the above if the poster had luck with this part. Would it be a functioning replacement for the original? Or did anyone find a switch where I could reuse the old original olive-coloured paddle with?

Thanks!

[SilverSolder]

LOL, all the old Hitachi scopes are coming out to play.

I have a V-660 that still comes in handy as an extra couple of channels in some situations.  It was an eBay find about 15 years ago... 

It has always had a "weak" selector switch - not bad enough to outright require repairing, but mildly irritating nevertheless (on an otherwise excellent scope).

Good to see it can be fixed,  this thread has inspired me to take a look!

[rbm]

Or do I have to try DigiKey’s 360-3390-ND (A28KB-BH)?  ... Would it be a functioning replacement for the original?

Hi,  This NKK A28KB-BH switch from Digikey should be a drop-in replacement for the OEM Fujisoku ALE2S-2M4-10-Z paddle switch. It was for me (see Posting #32).  The switching  configuration (DPDT-Centre off) and mechanical properties (2.54mm contact spacing and 5.08mm row spacing, switch body height and paddle size) are all equivalent.  You can purchase with confidence.

[Moonbase]

Thanks a bundle, Robert! Your confirmation is much appreciated.

I wonder if I should order two of those, to find out if it was possible to somehow adapt the original paddle to it … :-) I just like it when things look original again, I guess.

In general, I’m really impressed with the quality of the V-1065C. Bought new about 30 years ago (unbelievably expensive then), 20 years of service, survived about 5 times moving house and 10 years of hibernation in the cellar and still as good as ever (well, except the switch which stuck a few days ago). All caps still fine, inside looks beautiful, all switches (except S1603) good, BNCs shiny, intensity good, and focuses as sharp as a needle still. Wow.

[arw]

I also did the same freq counter hack on a VC6025 and it worked.
Was a pig to get to the links as they are under an add on board.
This daughter board has four standoff wires to secure it to the motherboard, cutting two of these enabled the daughter board to be lifted enough to get to the links. However putting it all back and resoldering the cut standoff wires,  I am fairly sure the trace is now not as pin sharp as it was before.
No amount of focus, intensity or astigmatism ajustment would bring it sharper.
A lot of cables had to be moved to get the board out enough to do the mod, so possibly the cable routing is quite critical in some area.
Will have to spend some time to debug this. A case of if it ain't broke don't fix it!

[ulyanoff]

Hello guys! Maybe the author will tell you how to remove the handle v / div? Just vertically pull fails. Hitachi V-6025(Grundig SO50) Thanks !

[ulyanoff]

Hello guys, does anyone have a broken oscilloscope from the V660, V665, V695, V1065 series, or maybe you know where you can buy the front frame and filter of the oscilloscope? Thanks

[wn1fju]

Old post, but I just recently came across it.  I can confirm that the hack mentioned earlier to enable the frequency counter also works on the 60 MHz Hitachi V-665 oscilloscope. 

It was fairly easy to do without first swinging the power supply out of the way.  I merely reached in there on an angle, cracked off the existing zero ohm resistor and soldered a jumper wire across the adjacent pair of pads.

As also mentioned before, there is an inaccuracy with this enabled option.  Mine reads consistently 0.55% low.  That is, a 1000 Hz waveform reads 994.5 Hz, a 10 kHz waveform reads 9.945 kHz, ...., a 10 MHz waveform reads 9.945 MHz.  When making measurements using the cursors (1/T), I do get the correct numbers, however.  The frequency measurement option appears only to go down to a lower limit of 50 Hz.

[pbs74]

Since this thread got resurrected anyway, it seems to be the only one for this model on this great forum, and I happen to own the basically similar v1565 model that is shown in this new video that forum user oz2cpu added to his YouTube channel today, I am going to add a link to it here as reference for any future readers. The video covers most of the functionality, along with high level tear down:
 

[wn1fju]

pbs74:  Very nice video, thanks.

Yes, I did have to consult the manual on the somewhat puzzling way of using the toggle switch and the adjacent knob.

I have resurrected a few Asian-produced analog scopes (BK Precision, EZ, Iwatsu, Leader, Phillips, Tenma), as well as the usual USA Tektronix and HP units.  I find the HItachi scope among the best.  Fortunately, my V-665 mostly worked when I got it (needed some cleaner sprayed in the pots/switches).  It looks a little challenging to rip it all apart for servicing.