Hello everyone, today I picked up off Facebook Marketplace a couple of Panasonic Toploader VCRs from 1980 a PV-1650 and a PV-1750 and the PV-1750 still has its original Wired Remote with it yet and the PV-1650 still has its original Dust Cover with it yet.

The Issues I'm having with them is the same with both units and that is that the take-up reel won't turn when the tape is loaded into the VCR after hitting play and the tape is loaded up against the head drum, it loads the tape into the mechanism, but then after a couple of seconds it backs the tape back out of the mechanism.

I did replace any and all bad belts in both VCRs (the weird thing is that the PV-1650 VCR's belts all failed by breaking in half rather than the classis "turn to goo" or "dry-rot" failure seen in most VCRs of this age, in fact most of the belts in both of these VCRs (including the broken belts in the PV-1650, were still soft and supple yet.)

Also in the PV-1750 the VCR will Rewind and Fast-Forward just fine, it just won't play, and the PV-1650 won't rewind, or Fast-Forward in addition to not playing.

Any ideas as to what might be causing the take-up reel to not spin in these VCRs when pushing play or to not fast-forward and rewind?

Any ideas as to what might be causing the take-up reel to not spin in these VCRs when pushing play or to not fast-forward and rewind?

In the PV-1650, there's a separate play idler tire at the right reel where the thin counter-belt is mounted. Clean the tire.

In the PV-1650, there's a separate play idler tire at the right reel where the thin counter-belt is mounted. Clean the tire.

OK, thanks, I will give that a shot. :thmbsp:

What about the PV-1750?

OK so its definitely the idler tires that are bad (they are cracked and have no grip left to them even after a cleaning)

I need to figure out what size of Idler Tires i need for these VCRs because all of the sites I've looked at (SMC Electronics, Russel Industries, etc.) list the parts by diameter (I. D. and O. D.) and Thickness but not by model number that they could be used on.

And Unfortunately I don't have access to the Service Manuals for these VCRs.

Any ideas as to what I need?

OK so its definitely the idler tires that are bad (they are cracked and have no grip left to them even after a cleaning)

I need to figure out what size of Idler Tires i need for these VCRs because all of the sites I've looked at (SMC Electronics, Russel Industries, etc.) list the parts by diameter (I. D. and O. D.) and Thickness but not by model number that they could be used on.

And Unfortunately I don't have access to the Service Manuals for these VCRs.

Any ideas as to what I need?

A digital caliper would come in handy.

https://www.amazon.com/Digital-Caliper-Sangabery-inches-Vernier/dp/B07VSVMWTJ/ref=sr_1_1_sspa?crid=1DR0YYAEPHCT1&keywords=caliper+measuring+tool&qid=1668796428&sprefix=calip%2Caps%2C219&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

jr

Hi. For the PV-1750, check whether the play idler (circled in red) is making contact with the take-up spool during play/record. This idler is driven by a belt so that might be the culprit. The NV-7000 or PV-1470 service manual might help. Shoot me a message if you need them.

OK, thanks, I will give that a shot. :thmbsp:

What about the PV-1750?

I'm not a fan of the PV-1750 or PV-1770 (with wireless remote). Belts, idler tires, and sensor lamp failed repeatedly more than the other vintage Panasonic VCR models.

OK so a little update on these VCRs, the PV-1650, I was able to find some replacement idler tires for it, but for some reason it still won't play (it rewinds and fast forwards just fine) but when you hit play it will load the tape against the heads like its supposed to but it won't actually play the tape (move the reel tables) and then it just loads the tape back into the cassette after a few seconds, so I'm not sure what is going on, I checked all of the belts related to the playback mechanism and replaced them all, so I don't know what else could be causing the VCR to not play, and all the motors are fine because they all spin up as they should when powering on the VCR, the service manual for the VCR just lists belts as being the only issue that could cause the VCR to fail to play, but I've alreay replaced all of the belts, unless the belts I used were not the proper length (too long) and weren't supplying the proper tension for the reel tables?

The PV-1750 I was able to get it to Rewind and Fast Forward as well, and the playback idler needs a new tire for it, but I can't seem to find one that is the proper diameter (its around an inch in diameter for the outer diameter and about 7/8" inner diameter), and I had ordered an idler tire assortment from one of the electronics parts suppliers and they didn't have any idler tires of that size in their assortment for some reason, they had one that was the next size up from that one but not that exact size, and that's all that's keeping the PV-1750 from working properly, even the remote was fully functional still when I tested it.

This may not be helpful at all, but I have had the same problem in U-matic machines, obviously not the same thing as VHS, but anyway the problem was caused by a failed or mis-adjusted microswitch which tells the logic the tape is threaded and ready to play. If it doesn't get this signal it will unload the tape. You might check to see if there is such a switch in your machine.

This may not be helpful at all, but I have had the same problem in U-matic machines, obviously not the same thing as VHS, but anyway the problem was caused by a failed or mis-adjusted microswitch which tells the logic the tape is threaded and ready to play. If it doesn't get this signal it will unload the tape. You might check to see if there is such a switch in your machine.

Well according to the service manual for my VCR there's a Take-up and Supply Phototransistor that I think is performing the same function as the "microswitch" you're referring to. Would something like that failing cause the troubles I'm having?

Well I got the PV-1750 to play tapes finally, it was a combination of a bad play idler tire and a belt that was too big on the underside.


But now that I got it playing tapes again, I've noticed that it plays tapes too slow, and I'm not sure why.

When its playing the audio sounds like a 45 RPM record being played at 16 RPMs, and the picture has large scanline bars going across the screen that look like a movie having tracking issues but its not a tracking issue because its not correctable with the tracking controls.

I can make a video and post it to youtube so you can see what I'm talking about if that's necessary.

What speed is the tape recorded at and what speed does the machine report it's playing at (if it can report that)?

If it's got an electrical problem such that it's trying to play a SP tape at LP or EP that could account for what you describe. I've seen decks do that before. I typically junk decks when they get that bad if they aren't anything special especially the newer ones that do everything in 2-3 chips.

What speed is the tape recorded at and what speed does the machine report it's playing at (if it can report that)?

If it's got an electrical problem such that it's trying to play a SP tape at LP or EP that could account for what you describe. I've seen decks do that before. I typically junk decks when they get that bad if they aren't anything special especially the newer ones that do everything in 2-3 chips.

I'm not sure, the VCR in question has a switch on it that can go through SP, LP and SLP but I don't see anything on the VCR that tells me what speed its playing at (that I can see of) I do know that I tried several tapes on it and it did the same thing on all of the tapes I tried out.

The tapes I used to try out the VCR were all tapes that were around 50 minutes or longer up to about 110 minutes or so so I don't know if that says anything about the speed the tapes were recorded at or not, but the boxes that held the tapes didn't say what speed they were recorded at.

The VCRs that are the subject of this thread I think would be worth trying to fix because they are both 4-head VCRs and at that they are very early 4-Head VCRs.
Plus I've always wanted a top-loading VCR with a wired remote to monkey around with because I went to a church daycare when I was a kid that had some of these types of VCRs and always remembering how much of an interesting thing they were because I had up to that point only ever seen front-load VCRs but never a top-loader and that was what kind of got me interested in old electronics.

Also they are very solidly built units and they have several boards inside for controlling everything instead of having things all on one or two chips like the more modern VCRs did, and also they have nice big Linear Power Supplies instead of Switchmode Power Supplies which make them nice units to work on.

Anyways is there anyway to figure out what speed the VCR is playing at or what speed a tape is recorded at when the VCR doesn't show a playback speed or a tape doesn't say what speed it was recorded at?

UPDATE: I used another VCR I had laying around that was known working and did show the tape speed, and the tapes I tried using to test the VCR with were all SP mode tapes, and the VCR does play SP mode tapes but doesn't seem to be able to detect them properly. I found a tape that was recorded in EP mode and I'll see if it can handle one of those, if it can, perhaps maybe the switch inside the VCR that detects the playback mode of the VCR got "stuck" and so it just needs another tape that can "free-up" the switch. :scratch2:

The playback speed is not sensed with a switch. It's detected from the linear control track of the tape by the electronic circuits that control tracking.

Usually the only user speed control is for recording mode only.

If it's that old it's probably worth trying to fix even if it's a complex electronic issue, but a service manual with schematic is going to be critical to success.

A further update: The VCR will play EP recorded tapes fine (even though it doesn't have an EP mode option in the record speed switch, but I'm not sure what EP Mode would be the equivalent of in terms of SP, LP and SLP)

So either the tape speed detecting circuit inside the VCR is defective so as to not allow it to detect SP tapes, or another thing I thought of is that there's a drive belt on the topside of the VCR mechanism that goes from a pulley in the middle of the VCR Mech. to the playback idler and perhaps when I replaced that belt I put the wrong size belt on that pulley system and its causing the VCR to play at the wrong speed. :scratch2:

A further update: The VCR will play EP recorded tapes fine (even though it doesn't have an EP mode option in the record speed switch, but I'm not sure what EP Mode would be the equivalent of in terms of SP, LP and SLP)

So either the tape speed detecting circuit inside the VCR is defective so as to not allow it to detect SP tapes, or another thing I thought of is that there's a drive belt on the topside of the VCR mechanism that goes from a pulley in the middle of the VCR Mech. to the playback idler and perhaps when I replaced that belt I put the wrong size belt on that pulley system and its causing the VCR to play at the wrong speed. :scratch2:

EP and SLP are the same speed. Different brands used different names for that speed for God only knows why.

If it's tracking and playing perfectly at SLP/EP speed with an SLP/EP tape it's probably an electronic problem.

The playback speed is not sensed with a switch. It's detected from the linear control track of the tape by the electronic circuits that control tracking.

Usually the only user speed control is for recording mode only.

If it's that old it's probably worth trying to fix even if it's a complex electronic issue, but a service manual with schematic is going to be critical to success.

I do have a couple of Service Manuals for this VCR, but they are Sam's Photofacts that I downloaded from their website, so the schematics and what not are cut up into pieces.
Could a bad capacitor in the control board cause these issues? I know this unit uses the old Matsushita caps that were notorious for failing over time (the purple ones.)

So what part of the service manual would I look under to find that circuit, so I can start troubleshoot it?
Is there a specific name for that portion of the VCR Circuit? I'm asking because the Service Manuals I have go by the names of what Panasonic put on each of the boards (ie Servo Board, etc.)

OK, so I tried out an LP recorded tape in the VCR and that also had some trouble playing in the VCR, so apparently whatever circuitry is involved with the VCR reading the speed of the tape on the control track on the tapes must control the SP and LP together and SLP is controlled separately from the SP and LP modes.
Although LP mode even though it wasn't playing at the right speed it was a much clearer picture (not as much sync issues) as the SP mode had, in SP Mode the picture had terrible sync problems (vertical and horizontal hold issues.)

Also how common was it for a VCR to have a failure of the speed sensing control system? I'm asking because this is the first VCR I've worked on that had this issue out of about 30+ VCRs I've worked on in my nearly 20 years of working on VCRs for people or for myself.

I had a similar problem with a JVC HR-D470U. It was a high ESR cap in the circuit the reads the control track.

I had a similar problem with a JVC HR-D470U. It was a high ESR cap in the circuit the reads the control track.

I realize a JVC VCR is Completely Different than a Panasonic/Matsushita VCR in how the Circuit Boards are labeled and layed out, but what board was it that was controlling the control track reading on the VCR? Was there a specific name for that circuitboard? I have the service data for my VCR but have no clue where to begin to look for that particular circuit on my VCR and it doesn't help matters any that the VCR has about 10+ circuitboards in it that all have a different name for them.

Haven't dug that deep into a deck that old with that issue but if I wanted to figure out which board(s) are involved I'd trace the control track wiring off the stationary head (which also contains the linear audio head on most decks) to a board and also trace the head drum and capstan motor wiring to a board. Those boards are likely involved. The older the VCR the more spread out the circuitry the first models may have read the control track on one board and passed it to 2 separate servo boards, the most recent ones did everything in the entire deck on one board. How muchand what was on one board in early decks sometimes has more to do with how compact they could build it by putting things certain places than logical placement.

If there's block diagrams in your service literature that may help you find things too.

Haven't dug that deep into a deck that old with that issue but if I wanted to figure out which board(s) are involved I'd trace the control track wiring off the stationary head (which also contains the linear audio head on most decks) to a board and also trace the head drum and capstan motor wiring to a board. Those boards are likely involved. The older the VCR the more spread out the circuitry the first models may have read the control track on one board and passed it to 2 separate servo boards, the most recent ones did everything in the entire deck on one board. How muchand what was on one board in early decks sometimes has more to do with how compact they could build it by putting things certain places than logical placement.

If there's block diagrams in your service literature that may help you find things too.

OK, so I figured out that the control track reading is controlled by 2 boards in this VCR, the Audio Board and the Servo Board, and sure enough when I took those boards out and looked them over they had several electrolytic caps that had spewed their guts (the green corrosion on the wires coming out of the bottom of the capacitors.)

So when I replaced all of the ones that were visibly defective, then I put the VCR back together and sure enough it started playing LP recorded tapes properly, but its still not playing SP tapes properly yet.
So I'm going to have to go back over those boards again and see if there were some capacitors that I missed that weren't as obvious looking and replace those, and I think it will be good to go. :thmbsp: :yes:

Well I double checked the boards I worked on earlier and I found several more bad caps I missed, so I replaced those as well, and in total I replaced between the audio board and the Servo Board a whopping 13 capacitors which all suffered from the green corrosion on the capacitor leads, but unfortunately instead of making it better, it made it worse, somehow. :sigh: :tears:

it will still play LP and SLP (EP) tapes just fine but when you try and play the LP and SP tapes instead of getting a picture, I just get video noise (the same kind of noise you get if a tape's tracking is severely off) except that the tracking isn't off the audio is just fine (in LP Mode) and in SP mode it still won't switch to the correct speed.

And I'm not sure what else to look for because I've replaced all of the bad capacitors in the Servo Board and the Audio Board, and it only restored operation to LP Mode, SP Mode is still not functioning, unless there's something else I'm missing? :scratch2:

Double check that you didn't install any backwards or 10X or 1/10the value. Changing caps should not make it worse.

Transistors are not infallible. About the only deck that old I've done deep troubleshooting on was the first frontload Betamax (Zenith rebadge) that wouldn't run some key motors in play mode. One of the control transistors fried.

Double check that you didn't install any backwards or 10X or 1/10the value. Changing caps should not make it worse.

Transistors are not infallible. About the only deck that old I've done deep troubleshooting on was the first frontload Betamax (Zenith rebadge) that wouldn't run some key motors in play mode. One of the control transistors fried.

I definitely made sure to use the correct capacitance value, the voltage values were a tad higher than the originals on some of them because I didn't have any that were the exact voltage rating, but I figured that the voltage rating shouldn't affect it much as long as the capacitance value is the same.

As for the transistors I didn't think to check those, but the only time I've ever had issues with those was on some 1970s stereo receivers I've worked on where they popped and crackled out of one channel and it was one of the transistors in the amplifier section.

I will though double check to make sure I didn't accidentally install some capacitors backwards, because while they had the (+) and (-) clearly marked on the board, I might of accidentally stuck a capacitor in the wrong way thinking I had stuck it in the right way because I had been working on this thing for almost 8 hours straight without any breaks.

I checked the Slow/Still Board and found some more bad caps.

Oddly enough all of the caps I replaced that were bad were 47 uF 16v electrolytics except for 2 of them, did Matsushita have trouble with the 47 uF 16v caps they made in the early 1980s? :scratch2:

I don't think it's uncommon for small value electrolytic caps to fail after 30+ years! How are you checking the caps? For ESR?

I don't think it's uncommon for small value electrolytic caps to fail after 30+ years! How are you checking the caps? For ESR?

I was using a combination of checking ESR with an older analog ESR Meter, and visual inspection, all the caps I replaced had green corrosion on their lead wires; which from what I had seen on repair videos by Shango066 and Jordan Pier, they said that was a common issue with certain types of Matsushita caps in older Panasonic radios, VCRs and TVs.

I was just merely pointing out that it was interesting that the majority of the capacitors that were replaced in this VCR were 47 uF 16v capacitors, but there were plenty of 10 uF, 1 uF, 22 uF, 100 uF and 220 uF caps in the unit that were still fine yet (still had low esr, and no green corrosion.)

The weird thing is that whenever I take a board out which involves me having to remove the many cable plugs attached to them to repair the board, and then plug them back in to check the VCR's functionality, I always end up having to take the board back out unplug the cables and reseat them again in order for the VCR to function as it did before I removed the board, and I'm not sure why that is the case.

I hear you. I've been working on a couple of VCRs and 1 small PCB has 9(!) connectors! Two of which are ribbon cables that are supposed to be zero insertion force. I'm sure they are when they line up perfectly. I have the most difficult time getting these stupid things in! It must be old age. I can't open anything you buy in the store either! LOL

Oh and maybe those 47 uF 16v capacitors were from a crappy batch. Green corrosion sounds like electrolyte leakage to me.

yeah unfortunately even after replacing almost 2 dozen failed electrolytics out of this VCR between the Audio, Servo, Slow/Still and Skew boards the VCR is still not wanting to play SP recorded tapes properly.

Plus the VCR has developed a new issue, where the video coming from the VCR when playing tape is just a garbled mess of white noise with the video's audio coming through clearly in the background (LP Mode specifically does this), where it will start off playing the tape at the wrong speed but then after about 2 seconds the screen goes blank and then starts playing at the correct speed, but the video is nothing but a garbled mess of white noise.

The weird thing is that after I had initially repaired the LP Playback speed issue, the VCR played the tape perfectly right away (there wasn't any delay in the speed selection like there is now) and the video playback was crystal clear (no garbled video output like its doing now.)

The weird thing is that the video started acting up when I went over the Audio and Servo Boards a second time and replaced the rest of the bad caps I missed the first time I went over those boards.

That was when I then decided to go over the Skew Board and the Slow/Still boards as well to see if those would make any difference with the playback speed detection issue, and that's when I figured out that unplugging and plugging back in all of the plugs on the Audio board for some reason corrected the video issue initially.

But then when I recapped the Slow/Still Board and the Skew Board and plugged those back in and tested the VCR that's when the garbled video issue showed up and unplugging and plugging back in the cables from the Audio Board didn't fix the problem this time around.

That's why I was saying that replacing the capacitors on some of the boards in this VCR was somehow making the tape playback issues worse and not better, (because while I was able to fix the LP mode playback issue, the SP mode playback issue was still not fixed and the video playback quality went from crystal clear, to nothing discernable in no time flat.)

And I'm not sure what's going on with this VCR and why all of the sudden when I replaced about 2 dozen nearly dead leaky capacitors that the VCR is no closer to being repaired than it was when I first discovered it had a playback speed issue. :sigh: :tears:

Maybe the video heads are clogged? I believe there are different ones for different speeds. Try cleaning with alcohol on a folded piece of paper. Do not use any up / down motion. Just rotate the drum while holding the paper against the drum.

Maybe the video heads are clogged? I believe there are different ones for different speeds. Try cleaning with alcohol on a folded piece of paper. Do not use any up / down motion. Just rotate the drum while holding the paper against the drum.

I didn't think about that, and actually I did try cleaning the heads, but I used cotton swabs which I realize now was a no-no I'll try and and go back over the heads with paper and alcohol.

OK, so now I've replaced so far 42 capacitors in this VCR all of them of which had the green corrosion on the capacitor wire leads (the corrosion was on either one or both legs of the capacitors, but thankfully it wasn't bad enough to of eaten through the circuit board yet.)

I removed the Luminance and Chromanance board and replaced at least 2 dozen caps on that board alone (all of them had the green corrosion as well), and so far it seems that 99% of the capacitors I've replaced in this VCR were 47uF 16v capacitors with the other 1% being other values. :scratch2:

Did you get the picture back?

Did you get the picture back?

Yes the video came back, but only for a little bit, as soon as I hit the pause button and then hit it again to un-pause the movie the video started messing up again, so I'm not sure what's going on, although if I had to guess I probably need to replace all of the electrolytics on the audio board and the Servo board and not just the ones that had the green corrosion on them that I already replaced...:scratch2:

Maybe the head is clogged again?

Maybe the head is clogged again?

I let the VCR sit for a couple of days and the video is working again, but unfortunately the SP Playback mode still isn't functioning, LP and SLP mode is functioning properly but SP isn't.

I have a feeling that the Audio and the Servo Boards both need to be completely recapped, not just having a few capacitors swapped out here and there.

UPDATE: I finally got the speed issues resolved, I ended up replacing almost every single cap on the Servo and Audio boards in the PV-1750 except for one of the higher value caps and several super low value caps (less than 10uF in value, such as 4.7. 3.3 and .1 and .33 and .22 uF electrolytics, mainly because I didn't have access to those values of caps in the voltage I needed.)

But now I'm having issues with the video playback again, where the video is nothing but a garbled mess but the audio is fine.
And yes I already checked the video heads and that wasn't what was wrong with it, it acts almost like when a TV has an analog station (from an RF Modulator or DTV Converter Box) tuned in but its off frequency (referring to a TV with a knob tuner on it that you had to fine tune the signal, or a varactor tuner that has the station tuned in just enough so that the audio comes in loud and clear but the video is snowy and bouncy.)

Its making me think possibly something is up with the RF Modulator portion of the VCR (the UHF/VHF I/O section of the VCR that has the Channel 3/4 switch), because otherwise I don't know what else could be causing the video playback issues I'm having, I haven't tried to see what it does using the RCA Video outputs on the back of the VCR to see what that does, but unfortunately I don't have any CRT TVs that have built in A/V jacks.

I did try operating it with the RCA Output jacks and the video outputted onto the screen is the same, but I did notice that when I dinked around with the RF Modulator's channel 3/channel 4 switch on the back of the vcr the picture cleared up a little bit but then it went back to being a garbled mess.

Is the Video signal outputted to the TV screen controlled by the same circtuitry regardless of if its being put out through the RF Modulator or if its being put out through the RCA outputs? Or are the RCA Outputs and the RF Modulator Video outputs separate circuits in the VCR? :scratch2:

I'm so close to getting this VCR going, and the only thing holding me back right now is the video output signal right now. :sigh: :tears:

Maybe it's a cold solder joint or crappy connection somewhere. By moving that switch you are causing vibration. I'd poke around with a wooden chopstick or something.

I would think that the composite signal is sent to the RF modulator.

Maybe it's a cold solder joint or crappy connection somewhere. By moving that switch you are causing vibration. I'd poke around with a wooden chopstick or something.

I would think that the composite signal is sent to the RF modulator.

I'm not sure what's going on with it, I know that if I take the audio board and the servo board and the Chroma/Luma boards off the VCR fiddle with the wire cable connections and then put the VCR back together the video will go back to normal but then if I do a Forward or Reverse Search then the video goes bonkers again for no apparent reason, and I'm not sure what's going on with it and why it does that. I have a screen cap of what it looks like when the video is going beserk.

The Video when its working properly gives a rock solid still image (pause) and the picture during playback is really clear and probably the best picture I have seen on an old 4-head VCR.

Also apparently the SP mode is only mostly fixed because while it puts out a picture and audio that is normal sounding and looking you can still kind of hear a little bit of a "drag" in the speech but just barely and then there are lines that go across the screen periodically, its acting almost like the video is paused and you're doing a frame search, but its actually playing and has audio.

If any of this makes any sense to you.

As for the PV-1650 I'm waiting for the play idler tire to get rebuilt by Gary over at the Voice of Music Enthusiasts, because its one of those Idler Tire assemblies that you had to replace the whole assembly or get it rebuilt because the rubber tire portion of it was permanently affixed to the metal shaft, and the rubber was petrified on it so it wasn't allowing it to grip the take-up reel drum so it could play a tape, so I sent it off to Gary to have it rebuilt so that hopefully I can get that VCR checked out for functionality as well, and maybe see if I can get a remote located for it.

The rebuilt idler is supposed to be done and mailed back to me by the 21st of March.

OK, well a little update on the PV-1750 VCR, I tried it out again today and it worked just fine today, and the speeds were working as they should.

But there now seems to be a video issue for sure, but I'm not sure what's causing it or why its doing it, because its kind of random.

I was playing an old tape in it just now and it was playing perfectly but then I heard what sounded like the video heads (the head that spins around in the VCR) revving up a little bit and then slowing down back to the normal speed after awhile, and when it did this the video being outputted by the vcr lost horizontal sync (the horizontal hold went crazy) but then when the video head went back to normal speed the picture went back to normal but with a slightly off center picture that would bounce back and forth between the right and left hand side of the screen before finally going back to normal.

I know I've heard about capacitors going bad on the board that controls the video head rotation/speed but I'm not sure what board does that in this VCR, I know this VCR has 2 "Control Boards" but I'm not sure which of those boards if any of them would control the video head.

Thanks for your help in this matter.

Its finally working! I just left the VCR plugged in over night and tried it out this morning and its been working fine ever since.
I watched Bruce Lee Enter the Dragon all the way through without any issues. :banana: :thmbsp:

I'll bet it's a cap that's bad. Maybe leaving it powered on reformed it.

I'll bet it's a cap that's bad. Maybe leaving it powered on reformed it.

That's what I was thinking, but I wasn't sure where the cap was, or what board to begin to look at for that cap, because there are about a dozen circuit boards inside of this VCR and some of them aren't the easiest to get to, and the Sam's wasn't much help in regards to telling me which board controlled what, and they didn't really have a troubleshooting section in the manual to trace down certain issues with.

Well I just started working on the PV-1650 VCR the other day and I replaced all of the Belts and had the play idler rebuilt by Gary over at the Voice of Music Enthusiasts and the VCR is still having issues with not wanting to play a tape after loading the tape up to the heads.

I have a copy of the Factory Service Manual from Panasonic that I got from Sam's which they sent me that because they didn't have their own service manual for the PV-1650 uploaded into their server database and that manual was very helpful (a lot more helpful than the Sam's Photofact manual for the PV-1750 was).

I figured out that there is a board that specifically drives/controls the loading and playback mechanism of the VCR (more or less the logic board for the VCR that controls whether the VCR mechanism plays, rewinds, fast-forwards, pauses, etc.) and so I removed that board from the VCR and looked it over and sure enough basically every single capacitor on that board was bad (either dead or had an ESR measurement of 2 Ohms or higher) and was also leaking electrolyte.

So I'm working on recapping that logic board so I can see if that will fix the VCR so it will play again.

Hopefully I'll have an update soon that will be a positive update where the VCR is working again (or at least mostly working again.)

Good luck!

An Update on the PV-1750:

I had an issue with it not working again and it turned out that the Audio Board and the Servo board both had some higher capacitance capacitors on them that I wasn't able to change previously because I didn't have those capacitors on hand, the servo board had a 100μF 16V capacitor and a 220μF 16V capacitor and the Audio board had a 220μF 16V capacitor that all three of those caps were leaking electrolyte out of the bottom, and so when I was finally able to replace them, the VCR started working properly again and its been working fine since.

The only thing I've noticed is that, when I go to turn on my 1974 GTE/Sylvania 25" Color Console TV that I have it hooked up to (so I can have a vintage setup) and play a tape on the PV-1750 the fine tuning on the TV gets screwed up and I have to re-fine tune the tuner on the TV until the picture locks in, any ideas as to what might be causing that issue?

Attached is a picture showing a bag full of capacitors which are all of the capacitors I replaced in the PV-1750 VCR to get it going, the other picture is showing my 1974 GTE Sylvania 25" Color Console TV with my Panasonic PV-1750 VCR hooked up to it and sitting on top of it, which is my vintage/retro TV Setup for watching VHS movies on and playing my NES and SNES games on, also I've noticed that after un-pausing a video the picture takes a few seconds to stabilize once its stabilized the video is perfect and plays fine.

Good work!

The RF modulator is off frequency internally, don't know if they can be trimmed back. The electrolytic capacitors are always a problem. 35+ years of heat/cool cycles and rubber seal deterioration they're going to fail, some show it more than others. My first Sony DVW-A500 DigiBeta died from leaking electrolytics, they dissolved the traces from the PC boards.

The RF modulator is off frequency internally, don't know if they can be trimmed back. The electrolytic capacitors are always a problem. 35+ years of heat/cool cycles and rubber seal deterioration they're going to fail, some show it more than others. My first Sony DVW-A500 DigiBeta died from leaking electrolytics, they dissolved the traces from the PC boards.

Thankfully none of the traces were damaged in this unit. :thmbsp:
And I was able to remove the capacitors without any damage to the solder pads.

As for the RF Modulator goes, I'm not sure if it can be adjusted or not, I'll have to look and see if the RF Modulator is actually removeable in the PV-1750, I know the PV-1650 has a removeable RF Modulator module that has adjustments, but I'm not sure about the 1750.

Most were a module as some areas needed a channel 2/3 or 3/4, I've even seen a channel 5/6 that was in a JVC Vidstar. Sony used a trimmer cap in theirs but anything goes with Matsushita, you could try tweaking the core slug in the modulator to see if that shifts the frequency enough for your sets AFC to grab on to, the other issue might be the AFC in the set is thermal and cold causes it to drift outside it's range. Without actually checking the carrier of the sources against a known standard it's difficult to say whos drifting around. I use a Motorola R2670 service monitor for my reference, it's only +8hz off a Stamford FS725 rubiduim standard on the 9th harmonic.