EW0125 - National NV-180 Portable VCR Investigation & Repair

This started as an attempt to show repairing a VCR head by re-lubricating the 'Hydro Dynamic Bearing' used in Compact National / Panasonic NV-180 and other model VCRs. Ended up being a long teardown and investigation.
In addition to the multiple National NV-180 VCRs, we also look briefly at a few similar models:
Canon VR-40
National AG-2400
National AG-6400
Panasonic PV-8000
I expect to make some move videos about restoring the Video heads by re-lubricating.
If you want to see more electronics and related things, follow me on Twitter: / electricelecami
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[@fagear]

Thanks for the video about these beautiful machines! I have some notes: 0:37 - NV-180 exists both for PAL and NTSC regions. NTSC one almost always silver, PAL can be silver or black. AG-2400 is the same machine, but put by Panasonic into "professional" category (hence "AG-") and has dark gray case. PV-8000 is upgraded version with stereo sound and more tape speeds, PV-9000 upgraded yet again with HiFi stereo. 01:35 - Panasonic OEMed NV-180 (and PV-8000, PV-9000) for many manufacturers, such as Bauer, Blaupunkt, Bosch, Canon, Grundig, Magnavox, Olympus... 10:40 - I have a short video on my channel for replacing and re-oiling the drum on NV-180 32:44 - that's rebranded PV-9000 47:50 - you don't need to disassemble the machine, reoiling can be done all from the top, no need to remove bottom part of the drum from the transport 57:48 - S-VHS version called AG-7400 01:03:38 - it's dangerous to remove "don't loose" screws without removing top drum because it drops down on the motor and head tips can be wedged and cracked from contact to the bottom part (made that mistake myself and cracked a head) 01:09:24 - not sure that a greese should be in the bearing, I've seen liquid oil in drum motors that were not dryed out yet and I put ATF III oil in there, grease only onto the trust plate, wrong oil causes motor to overheat and stop 01:22:48 - that snow usually indicates worn out/cracked head, pause uses heads in a different configuration (look for the table in service manual), also for NTSC machines all speeds should be tested because different heads used for different speeds I also have three long videos about NV-180 history and repairs on my channel.

[@Elecami]

Thank you for the useful and detailed information. So I should put an oil down the shaft and grease only on the top? I just got another video done where I tried on the AG-2400 with only putting grease on the top. It needed to have some down the shaft too I think.

[@fagear]

@@Elecami yes, I think oil on the shaft and grease on the plate. Not every oil works there, I've tried engine 5W-30, general purpose oil and silicone oil - drum spins but after some minutes of work it stops. Overheats maybe. Only automatic transmittion oil worked fine for me. Please check spam folder for comments, I've left a link to my video with reoiling the drum, but seems like YT has hidden it (it has video ID IZcUjTuT5c4).

[@oriole8789]

It never ceases to amaze me how much equipment you've hoar-- I mean, collected. Absolutely surreal. Enough to open your own museum~ The swappable battery/ac adapter thing is honestly really cool. I wish the concept was used more often elsewhere. Since the serial protocol is straightforward and well documented (those booklets were amazing, thanks a lot for showing), you could easily run these VCRs with some custom PC software if you wanted (or write something in LabVIEW since that's your expertise). Or you could make your own 3D printed remote control with some cute custom graphics~ Regarding greases, I would guess instinctively that the grease has to have somewhat reduced viscosity in order for the microgrooves in the drum assembly (including the spiral thingy) to move it around effectively, as opposed to just stirring it, but too little viscosity would cause it to leak out so it probably has to be "just right". Since the previous grease "dried out", it probably wasn't the best quality. A common issue with greases that are mixtures of stable thickeners (for example, PTFE) and stable oils (for example, PFPE), is that when left alone for a long time, the thickener and the oil will separate (even though those individual components are incapable of degrading). As such, the oil can leak out, increasing the viscosity of the grease over time. Often, the "quality" of the grease (for instance industrial-grade vs aerospace-grade) is differentiated by reduced thickener/oil separation for higher grade greases. Thanks as always for your videos!

[@Elecami]

Thanks. Excellent info about the grease. It is weird, I will need to look more carefully next time, where did it go? There is no where for it to leak out to. the bottom part of the head assembly is sealed. and it would make a big mess of the head surface it it got there. My collection is a bit out of control. making these videos is a way I can become ok with getting rid of some of it.

[@WolfmanDude]

You are truely the best, there is soo much invaluable information in this video! Watching this was soo surreal after I spend hours staring at that cut-away diagram of the video drum; trying to understand how the rotary transformer works and how you can take it apart. I was glued to my screen when you "loosed" those 3 scary screws :D That warning in the service manual made me so afraid! I think the warning refers to the rotating part "crashing" down after removing the 3 screws. I will insert a shim into the gap of the video drum to prevent this. I cannot thank you enough!

[@Elecami]

Thanks. I plan to do another Video with that AG-2400 to do the head re-lubrication again. I have been thinking about it and probably the reason to not touch those screws is that the plate they hold on can tilt around and it should be re aligned correctly to sit perfectly flat against the top of the shaft. Yea the crashing down part, I didn't consider. I'll look into these things next time.

[@WolfmanDude]

@@Elecami I know someone who is an expert in bearings, I will ask him what kind of oil or grease is right for those kind of bearings. I will let you know if I find something out! Edit: These are called "Spiral groove bearings"

[@laetlaet6130]

عمل ممتاز

[@Elecami]

Thank you.

[@fabriziooldrini6888]

I had a pal nv180 branded Philips, with the same Panasonic camera you show here. I shoot a video of my first USA journey, August 1988. The nv-180 was never stereo, the one you show here must be a special USA version.

[@Elecami]

Good choice of video camera setup 🙂 I have noticed there are more models of Stereo VCR in US Market than others. Not sure why that is.

[@fabriziooldrini6888]

@@Elecami that's because Americans get the best...

[@Elecami]

@@fabriziooldrini6888 I am not sure about that. The non-HiFi VHS audio is pretty terrible. Narrow track width and very slow tape speed goes not give much bandwidth for audio. Maybe it is related to easier hook up of cable TV decoders back then. I have no idea.

[@fabriziooldrini6888]

@@Elecami I had in my hand an hirachi vt7e which is stereo. When they sold prerecorded hifi film VHS, these tapes had also the slow linear stereo audio, at least the high quality movies. On the Hitachi vt7e you could even do a sound dub from one channel to other. I have s vt7e now but needs new belts, the original ones are all melted. Got also 2 Panasonic m7, same belt problem

[@Elecami]

@@fabriziooldrini6888 Sad part is, after replacing belts, there will probably be capacitors going bad.

[@sw6188]

I still have a couple of NV-180 recorders, along with the matching tuner / timer VW-ET180. I haven't used them for so long I'd be surprised if they even powered up now. Belts are probably bad as well. Time and lack of use doesn't do these decks any good.

[@Elecami]

No belts in this one. It is a nice design. Probably will still work. But the grease in the head bearing might have gone bad.

[@sw6188]

@@Elecami It has been so long since I worked on an NV-180 I can't remember what's inside. Is it all direct drive? Mine are in storage so can't access them easily at the moment.

[@Elecami]

@@sw6188 Yes, direct drive.

[@sw6188]

@@Elecami That's a blessing (I think) - I won't have to worry about tar belts, probably find all the Matsushita caps have leaked all over the PCB and destroyed it!