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#1
08-11-2023, 07:00 PM
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Jvc hr-d470eg
Hi everyone.
I bought this vcr, I don´t know if you are like me, but I´ve never heard of a vcr with a side loading mechanism... It was working, but the only problem was that as I loaded the tape, it started playing and a second after stopped, FF an RW equal. I have seen some youtube videos that showed that maybe was the reel sensor, the only difference was that mine, changed the counter from 0000 to 0001 or 0002, so I was not convinced that it was the problem... Dispite that, I connected my bluetooth receiver through rca cables to input, and I only had left channel in stereo, only in mono I had both channels, so I decided to disassembly it, download the service manual, and order all electrolytic capacitors for all boards, including PSU, in the hope to have a 80´s fantastic engeneering device for mora 40 years or so... I took pictures of all boards and connections, but after all caps replaced, I swapped power transistor plug "CN6" to "CN5", it has the same pin count so I stupidlly wrong connected it, when I plugged it to mains, the "Fuse2" burned all of the sunned, then I connected the mains to my serial bulb short protector and replaced the fuse, but everytime i turn the mains on, the fuse blowed, until I figure out that the plugs were connected wrong. My question is... After connecting all right, I measure voltages in PSU and none look like in the service manual. I replaced again all electrolytics in th PSU, but still the same. I´ll attach all the service manual I have and pics and video from my device. https://drive.google.com/file/d/1oeP...usp=drive_link https://drive.google.com/file/d/1Zgj...usp=drive_link https://drive.google.com/file/d/1437...usp=drive_link Thank You all, Hugo. 
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#2
08-12-2023, 01:18 PM
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I would start by pulling the power supply and checking Q1, Q2 and Q4. With the power supply still separated from the VCR apply power to the PS and test voltages. You should get all except the switched one. (You have no signal from the processor to turn it on.) After you have a working power supply, pray that nothing else was fried in the VCR! Good luck with your project!
I bought an HR-D470U (US version) new in 1987 and it was not cheap! I still have it. It's sort of working but has some problems with the display. I have bought a couple more of these as parts / not working. One had a bad cap and open resistor in the power supply and after repairing the PS, plays with a great picture.
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#3
08-14-2023, 06:04 AM
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Thank You redk9258.
I measured the Q1, Q2 and Q4, and these are the values I got. I have no shorts in none of them. Q1 B-550mv C-21V E-1,8V Q2 B-550mv C-21V E-0V Q4 B-0V C-12V E-0V. I checked all resistors and diodes, and none are oppened or shorted. Thank You again, Regards, Hugo.
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#4
08-14-2023, 04:24 PM
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With the power supply isolated from the VCR, the fuse no longer blows? The voltages you gave are referenced to ground? If so. they do not match the schematic.
Expected voltages: Q1 B 13.2 C 17.7 E 11.9 Q2 B 13.6 C 17.9 E 12.3 Q4 B 6.0 C 8.9 E 5.4 It makes sense that Q4 doesn't have the voltages because it comes from the switched part of the PS. Q1 doesn't make sense to me. It's emitter says it's 11.9 but ends up at 17V on CN1, pin 6 ??? I think they have wired crossed to pins 6 and 7 on the diagram! Anyway, with power applied, you should have the voltages listed on CN1, CN2 CN3, CN4, CN5 and CN8 that are not marked switched.
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#5
08-14-2023, 09:02 PM
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I redk9258.
As allways, You´re a 5 star person, you we´re the only one who answer me in all questions about vcr´s! I really really thank you! After measuring on cold, all the PSU components, I figured out that when I mixed up "CN6" to "CN5" the "R1" 10ohm fuse resistor burned out with "Fuse2" Thank God it did, I replaced it with a 2W 10ohm just to test and the VCR came to life again, all two audio channels work, beautifull sound, but the reel sensor doesn´t work, it starts to play and stops just like before. I saw a chinese video on Youtube that had the same problem, I thought my problem was only caps, I was wrong... I can find the sensor, but only in foreign sites, that dont ship to Portugal. If you or someone can ship the sensor to me I´ll pay for it. The sensor it this... https://www.donberg.ie/descript/g/gp_3a21.htm Thank You all!! Hugo. Quote:
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#6
08-14-2023, 10:40 PM
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I would find another machine to harvest it from. Are you sure the part is bad?
No affiliation... https://www.ebay.com/itm/295853421181 You took on a heck of a project recapping that thing! I want to do mine but I'm afraid! LOL So, you are in Portugal? I think I bought an OEM rubber kit for mine from a guy in Portugal. It had the belts, idler, pinch roller, and back tension band. I wish he had more!
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#7
08-14-2023, 10:55 PM
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Quote:
Don´t be affraid! I replaced all caps, I´m listening to music through my VCR, and it sounds great, after replacing the reel sensor it will be a 40 or more years machine!! These "machines" deserve all the love we give to them!! P.S.- Oh And Yes, I´m from Portugal, in Portugal, Beja! Come and visit us!  Was this site you bought the belts? https://webspareparts.pt/ No affiliation too...
Last edited by hugocarmo; 08-14-2023 at 11:01 PM.
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#8
08-15-2023, 05:24 AM
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No I bought them from a seller on ebay. If I remember correctly, he was on an island in the middle of the ocean. I found that out from the tracking information. It was an original JVC kit for our model VCR.
JVC P/N PTU96079 https://www.wagneronline.com.au/orig...-4373/1059/pd/
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#9
08-17-2023, 10:00 AM
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Could this one work like the original one?
It has 5 pins too... https://storage.googleapis.com/mause...s/096-3966.pdf Thank You.
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#11
08-18-2023, 03:54 AM
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Quote:
As I read online this is a common problem in older JVC VCR´s. And I saw this video on youtube that as the same problem as me and he replaced the photo interruptor and it worked. https://www.youtube.com/watch?v=FFHd2tOaNdQ Testing it as in the video I have the same symptoms, and when I press PLAY and PAUSE, the VCR remains in PAUSE and don´t stop, because at that state it´s no reading values from the photo interruptor. Thank You, Hugo do Carmo.
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#13
04-30-2024, 09:11 AM
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Quote:
Yes I was able to obtain one from a JVC HR-D530 that I bought but it was for scrape, the reel sensor model is the same, after replacing it the vcr started to act as normal!! Regards, Hugo.
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#15
04-30-2024, 10:01 PM
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Quote:
For now I´m struggling with a Panasonic NV-HS100 clone, a Blaupunkt RTV-966, it´s the same only the brand changes in EU. It have´s TBC, the problem is when I turn on the TBC, there´s an horizontal shake on the image, don´t know if it´s the TBC itself or another issue, I disassembled the TBC board, but don´t see any leaking capacitors, maybe replacing all of them it gets fixed... I´ll try that, one of this days Regards, Hugo.
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