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#1
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Any Panasonic VCR Experts In Here?
I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450.
They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? PV-V4540 head unit http://i126.photobucket.com/albums/p...IM002417-1.jpg PV-9450 head unit http://i126.photobucket.com/albums/p...IM002411-1.jpg PV-V4540 face http://i126.photobucket.com/albums/p...IM002414-1.jpg PV-9450 face http://i126.photobucket.com/albums/p...IM002413-1.jpg |
#2
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Any Panasonic VCR Experts In Here?
"Ron" wrote in message ... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? The arm in the centre is for static discharge. Without it, on a machine originally fitted with one - which most are - you tend to get little white dots on the playback picture. Provided the heads *are* exactly the same, then there are no alignment issues with head swaps on modern VCRs. It is only two screws, so give it a go. Normally, the screw holes are offset slightly to make sure that you don't get it on 180 degrees out. At worst, it just won't work. As a matter of interest, what are the symptoms for your diagnosis of failing heads on the first one ? Arfa |
#3
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Any Panasonic VCR Experts In Here?
Arfa Daily wrote in message
... "Ron" wrote in message ... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? The arm in the centre is for static discharge. Without it, on a machine originally fitted with one - which most are - you tend to get little white dots on the playback picture. Provided the heads *are* exactly the same, then there are no alignment issues with head swaps on modern VCRs. It is only two screws, so give it a go. Normally, the screw holes are offset slightly to make sure that you don't get it on 180 degrees out. At worst, it just won't work. As a matter of interest, what are the symptoms for your diagnosis of failing heads on the first one ? Arfa A child's plastic "toy" microscope of x20 or x30 magnification. Just the barrel is useful for inspecting with part of the objective end ground down at an angle, back to (or even into ) the lens, allows to get close enough for video heads to inspect, in situ , when illuminated with a torch. To inspect whether the gap is chipped and generally whether worn down too much. View in a downwards sense wherever there is enough clearance. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#4
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Any Panasonic VCR Experts In Here?
"Ron" wrote in message ... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? PV-V4540 head unit http://i126.photobucket.com/albums/p...IM002417-1.jpg PV-9450 head unit http://i126.photobucket.com/albums/p...IM002411-1.jpg PV-V4540 face http://i126.photobucket.com/albums/p...IM002414-1.jpg PV-9450 face http://i126.photobucket.com/albums/p...IM002413-1.jpg from the parts list pvv4540 uses the beliow listed upper cylinder head VEGS0427 ( A ) VEGS0428 ( B,C,D ) VEGS0429 ( E,F ) pv9450 uses VEHS0571 ( A ) VEHS0570 ( B,C ) VEHS0567 ( D,E ) not much help but swapping may not hurt |
#5
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Any Panasonic VCR Experts In Here?
In article , Meat Plow wrote:
On Wed, 02 Jul 2008 09:11:07 +0100, Arfa Daily wrote: "Ron" wrote in message ... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? The arm in the centre is for static discharge. Without it, on a machine originally fitted with one - which most are - you tend to get little white dots on the playback picture. Provided the heads *are* exactly the same, then there are no alignment issues with head swaps on modern VCRs. It is only two screws, so give it a go. Normally, the screw holes are offset slightly to make sure that you don't get it on 180 degrees out. At worst, it just won't work. As a matter of interest, what are the symptoms for your diagnosis of failing heads on the first one ? The OP should be advised that in certain cases (unless things have changed in the past decade)you need a head puller. I've replaced many voice coils from inexperienced techs who destroyed them while removing a head. He's not wanting to remove just the heads, he wants to remove and replace the whole cylinder with heads attached to the other unit. Its only 2 or 4 screws on the thing and you move it over and place it down in the other VCR.I have done this sucessfully from an old Mitsubishi U-760 to a U-770 if i remember right(Its been years). But with his situation, the parts are completely different between the units. I would advise against it with these two units. |
#6
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Any Panasonic VCR Experts In Here?
"nipperchipper" wrote in message ... "Ron" wrote in message ... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? PV-V4540 head unit http://i126.photobucket.com/albums/p...IM002417-1.jpg PV-9450 head unit http://i126.photobucket.com/albums/p...IM002411-1.jpg PV-V4540 face http://i126.photobucket.com/albums/p...IM002414-1.jpg PV-9450 face http://i126.photobucket.com/albums/p...IM002413-1.jpg from the parts list pvv4540 uses the beliow listed upper cylinder head VEGS0427 ( A ) VEGS0428 ( B,C,D ) VEGS0429 ( E,F ) pv9450 uses VEHS0571 ( A ) VEHS0570 ( B,C ) VEHS0567 ( D,E ) not much help but swapping may not hurt Given that info, it's probably not going to work right. Hifi sound is critical of correct head performance, so if there are any specification differences between the head drums, there will likely be a problem. As far as swapping the entire head drum assembly goes, you will often find that even identical-looking assemblies won't fit because a screw hole or chassis locating boss has been deliberately offset to prevent it. As for having to use a puller to remove the upper head drum (which I have always thought is a far more straightforward job than swapping the whole assembly) on some machines, that used to be a given, but I always found that Pans came off ok. Not that for some years it's been a viable proposition to replace heads, even on 'good' machines. The cost of the head drum alone, without any labour, exceeded tha cost of a bargain warehouse all singing and dancing machine with a shiny new 2 year warranty ... Arfa |
#7
Posted to sci.electronics.repair
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Any Panasonic VCR Experts In Here?
Meat Plow wrote: I see. I took the OP's description of "Head Unit" to mean replacing the head unit (unit with the heads in it that can be replaced separately.) and not the "whole cylinder" whatever that means. That is the upper and lower drums, spindle motor and the head electronics. Unscrew it from the chassis, unplug the cables and change the whole assembly. That is how heads are changed on R-R broadcast tape machines, like the 1" Sony machines we used at Ch. 55 in Orlando. If you were used to it, you could drop a new $1100 head into the machine in under 15 minutes, and be back in service. It came prealigned and tested. You didn't have to take the machine out of the rack or unhook anything else. It was one of the things I liked about Sony Broadcast Electronics.. -- http://improve-usenet.org/index.html If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm Sporadic E is the Earth's aluminum foil beanie for the 'global warming' sheep. |
#8
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Any Panasonic VCR Experts In Here?
On Jul 2, 4:11*am, "Arfa Daily" wrote:
"Ron" wrote in message ... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? The arm in the centre is for static discharge. Without it, on a machine originally fitted with one - which most are - you tend to get little white dots on the playback picture. Provided the heads *are* exactly the same, then there are no alignment issues with head swaps on modern VCRs. It is only two screws, so give it a go. Normally, the screw holes are offset slightly to make sure that you don't get it on 180 degrees out. At worst, it just won't work. As a matter of interest, what are the symptoms for your diagnosis of failing heads on the first one ? Arfa When the video starts to get noticeably bad a screen will pop-up that says the heads need to be cleaned. So for yrs I've been taking the top off and cleaning the heads when the screen appears. (white piece of paper with rubbing alcohol holding it against the heads on the upper drum while turning it counterclockwise - alcohol and Q Tips for the erase and audio heads) Put the top back on and everything is great until they get dirty again. So earlier this week the picture started looking *really* bad, and sure enough there is the screen telling me the heads are dirty...so I do my usual procedure, only this time, the picture still looks like crap. The warning screen isn't coming up, but previously recorded tapes in EP mode look horrible, any tapes I make in EP mode look horrible. Tapes that I've previously made in SP mode look OK and store bought movies look OK also. Not great, just OK. (Same with making a tape in SP) Before any of this happened, while watching a recorded EP mode tape if I were to hit rewind to back up the tape, about 25% of the upper screen was nothing but noise lines/snow. But, this would only happen if it was near the beginning of the tape. Once you got past a certain point (3/8ths - 1/2 way) this problem would go away. After cleaning the heads, this problem is still present. I can fix that problem by adjusting (big adjustment 1/4 turn) the feed side roller guide, but the picture still looks horrible. So, after reading many articles, I can only come to the conclusion that one of the 4 heads in the drum/cylinder went bad. I haven't had time to switch the heads yet, when I do I will post the results. Meatplow, after removing the 2 small screws, the upper part of the drum/cylinder, what ever you wanna call it, just lifts right off. |
#9
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Any Panasonic VCR Experts In Here?
On Jul 3, 1:54*pm, "Michael A. Terrell"
wrote: Meat Plow wrote: I see. I took the OP's description of "Head Unit" to mean replacing the head unit (unit with the heads in it that can be replaced separately.) and not the "whole cylinder" whatever that means. * *That is the upper and lower drums, spindle motor and the head electronics. Unscrew it from the chassis, unplug the cables and change the whole assembly. * *That is how heads are changed on R-R broadcast tape machines, like the 1" Sony machines we used at Ch. 55 in Orlando. If you were used to it, you could drop a new $1100 head into the machine in under 15 minutes, and be back in service. *It came prealigned and tested. *You didn't have to take the machine out of the rack or unhook anything else. It was one of the things I liked about Sony Broadcast Electronics.. Orlando huh? Wanna help out a neighbor? |
#10
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Any Panasonic VCR Experts In Here?
On Jul 3, 4:40*am, "Arfa Daily" wrote:
"nipperchipper" wrote in message ... "Ron" wrote in message .... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? PV-V4540 *head unit http://i126.photobucket.com/albums/p...IM002417-1.jpg PV-9450 head unit http://i126.photobucket.com/albums/p...IM002411-1.jpg PV-V4540 face http://i126.photobucket.com/albums/p...IM002414-1.jpg PV-9450 face http://i126.photobucket.com/albums/p...IM002413-1.jpg from the parts list pvv4540 uses the beliow listed upper cylinder head VEGS0427 *( A ) VEGS0428 *( B,C,D ) VEGS0429 *( E,F ) pv9450 uses VEHS0571 *( A ) VEHS0570 *( B,C ) VEHS0567 *( D,E ) not much help but swapping may not hurt Given that info, it's probably not going to work right. Hifi sound is critical of correct head performance, so if there are any specification differences between the head drums, there will likely be a problem. Well, that is an understatement. Put the head drum from the older working VCR into the newer one, there was no signal on the face plate for "HiFi". So I put it back into the - what was working unit - and NO HiIFi. Don't know what happened, but the newer VCR fried something in the older ones head drum. Now I have 2 Panasonics that don't work. |
#11
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Any Panasonic VCR Experts In Here?
Ron wrote: Orlando huh? Wanna help out a neighbor? I would, but I'm closer to Gainesville these days. Orlando was 20+ years ago, and I've slowly moved North since then. -- http://improve-usenet.org/index.html If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm Sporadic E is the Earth's aluminum foil beanie for the 'global warming' sheep. |
#12
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Any Panasonic VCR Experts In Here?
On Jul 3, 6:51*pm, "Michael A. Terrell"
wrote: Ron wrote: Orlando huh? Wanna help out a neighbor? * *I would, but I'm closer to Gainesville these days. *Orlando was 20+ years ago, and I've slowly moved North since then. Ha, that was about how many yrs ago I moved here. What a traffic nightmare this place has become since then. Used to be only I-4, now it's every major road. |
#13
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Any Panasonic VCR Experts In Here?
"Ron" wrote in message ... On Jul 2, 4:11 am, "Arfa Daily" wrote: "Ron" wrote in message ... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? The arm in the centre is for static discharge. Without it, on a machine originally fitted with one - which most are - you tend to get little white dots on the playback picture. Provided the heads *are* exactly the same, then there are no alignment issues with head swaps on modern VCRs. It is only two screws, so give it a go. Normally, the screw holes are offset slightly to make sure that you don't get it on 180 degrees out. At worst, it just won't work. As a matter of interest, what are the symptoms for your diagnosis of failing heads on the first one ? Arfa When the video starts to get noticeably bad a screen will pop-up that says the heads need to be cleaned. So for yrs I've been taking the top off and cleaning the heads when the screen appears. (white piece of paper with rubbing alcohol holding it against the heads on the upper drum while turning it counterclockwise - alcohol and Q Tips for the erase and audio heads) Put the top back on and everything is great until they get dirty again. So earlier this week the picture started looking *really* bad, and sure enough there is the screen telling me the heads are dirty...so I do my usual procedure, only this time, the picture still looks like crap. The warning screen isn't coming up, but previously recorded tapes in EP mode look horrible, any tapes I make in EP mode look horrible. Tapes that I've previously made in SP mode look OK and store bought movies look OK also. Not great, just OK. (Same with making a tape in SP) Before any of this happened, while watching a recorded EP mode tape if I were to hit rewind to back up the tape, about 25% of the upper screen was nothing but noise lines/snow. But, this would only happen if it was near the beginning of the tape. Once you got past a certain point (3/8ths - 1/2 way) this problem would go away. After cleaning the heads, this problem is still present. I can fix that problem by adjusting (big adjustment 1/4 turn) the feed side roller guide, but the picture still looks horrible. So, after reading many articles, I can only come to the conclusion that one of the 4 heads in the drum/cylinder went bad. I haven't had time to switch the heads yet, when I do I will post the results. Meatplow, after removing the 2 small screws, the upper part of the drum/cylinder, what ever you wanna call it, just lifts right off. Yes, that is normally the case with Pans. Sounds as though one of the heads may have become chipped, but it is also possible that one of them has become badly blocked. Sometimes when that is the case, it's necessary to get a bit vicious with it. A trick that was shown to me by a manufacturer's service course lecturer, is to hold a fingernail against a running tape, as it is around the head drum - so that you can feel the heads going "DRRRRRRRRR" against your nail, through the tape, if you see what I mean. It is amazing how quickly and how well this recovers a head that has become badly clogged from a tape that is moist from condensation, or is shedding oxide. It has got me out of trouble on many occasions. Arfa |
#14
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Any Panasonic VCR Experts In Here?
"Ron" wrote in message ... On Jul 3, 4:40 am, "Arfa Daily" wrote: "nipperchipper" wrote in message ... "Ron" wrote in message ... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? PV-V4540 head unit http://i126.photobucket.com/albums/p...IM002417-1.jpg PV-9450 head unit http://i126.photobucket.com/albums/p...IM002411-1.jpg PV-V4540 face http://i126.photobucket.com/albums/p...IM002414-1.jpg PV-9450 face http://i126.photobucket.com/albums/p...IM002413-1.jpg from the parts list pvv4540 uses the beliow listed upper cylinder head VEGS0427 ( A ) VEGS0428 ( B,C,D ) VEGS0429 ( E,F ) pv9450 uses VEHS0571 ( A ) VEHS0570 ( B,C ) VEHS0567 ( D,E ) not much help but swapping may not hurt Given that info, it's probably not going to work right. Hifi sound is critical of correct head performance, so if there are any specification differences between the head drums, there will likely be a problem. Well, that is an understatement. Put the head drum from the older working VCR into the newer one, there was no signal on the face plate for "HiFi". So I put it back into the - what was working unit - and NO HiIFi. Don't know what happened, but the newer VCR fried something in the older ones head drum. Now I have 2 Panasonics that don't work. I feel that to be highly unlikely, as the coupling between the heads and the amplification electronics is completely isolated by a rotary transformer, the primary of which is in the upper head drum, and the secondary, in the lower. Far more likely is that the screw-holes are not offset, and you have managed to get the upper drums 180 degrees out on the centre spindle. Unscrew the formerly good one again, and try turning it through 180 degrees, and see if the holes still line up. If they do, screw it down again, and retest. If that gets you back to working, then try your swap again, taking note of the same potential problem. Arfa |
#15
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Any Panasonic VCR Experts In Here?
On Jul 3, 8:00*pm, "Arfa Daily" wrote:
"Ron" wrote in message ... On Jul 3, 4:40 am, "Arfa Daily" wrote: "nipperchipper" wrote in message ... "Ron" wrote in message .... I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? PV-V4540 head unit http://i126.photobucket.com/albums/p...IM002417-1.jpg PV-9450 head unit http://i126.photobucket.com/albums/p...IM002411-1.jpg PV-V4540 face http://i126.photobucket.com/albums/p...IM002414-1.jpg PV-9450 face http://i126.photobucket.com/albums/p...IM002413-1.jpg from the parts list pvv4540 uses the beliow listed upper cylinder head VEGS0427 ( A ) VEGS0428 ( B,C,D ) VEGS0429 ( E,F ) pv9450 uses VEHS0571 ( A ) VEHS0570 ( B,C ) VEHS0567 ( D,E ) not much help but swapping may not hurt Given that info, it's probably not going to work right. Hifi sound is critical of correct head performance, so if there are any specification differences between the head drums, there will likely be a problem. Well, that is an understatement. Put the head drum from the older working VCR into the newer one, there was no signal on the face plate for "HiFi". So I put it back into the - what was working unit - and NO HiIFi. Don't know what happened, but the newer VCR fried something in the older ones head drum. Now I have 2 Panasonics that don't work. I feel that to be highly unlikely, as the coupling between the heads and the amplification electronics is completely isolated by a rotary transformer, the primary of which is in the upper head drum, and the secondary, in the lower. Far more likely is that the screw-holes are not offset, and you have managed to get the upper drums 180 degrees out on the centre spindle. Unscrew the formerly good one again, and try turning it through 180 degrees, and see if the holes still line up. If they do, screw it down again, and retest. If that gets you back to working, then try your swap again, taking note of the same potential problem. Arfa The upper drum(s) can only go on one way. It has a pilot hole for a guide and the screw holes are also slightly offset. Don't know what happened, but switching them fried something in either the units themselves, or in the upper drums. *Both* units with their original heads have video, but the audio is muddy. I cleaned both using the fingernail method you mentioned, followed up with paper and alcohol, no change. Oh well......... |
#16
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Any Panasonic VCR Experts In Here?
Ron wrote: On Jul 3, 6:51 pm, "Michael A. Terrell" wrote: Ron wrote: Orlando huh? Wanna help out a neighbor? I would, but I'm closer to Gainesville these days. Orlando was 20+ years ago, and I've slowly moved North since then. Ha, that was about how many yrs ago I moved here. What a traffic nightmare this place has become since then. Used to be only I-4, now it's every major road. I worked there in 1987/88, and the place was already a pain. I avoided I-4 as much as possible, and used 441 to go home in Lake county. Ch 55 was on Parkbreeze Ct, near 441 & Lee rd. Part of my time was spent at the transmitter sites in Orange City, or Lisbon, and the original studio site in Leesburg. It was amazing the number of people who drove like Orlando was still a farm town. they would stop short of the buried sensors in the roads, and force the light into the default cycle, leave three or four car lengths between them and the next vehicle. The worst were the ones who waited 15 seconds after the light changed, before pulling into the intersection at 5 MPH. (And never getting close to the speed limit) A few years later I worked in Altamonte Springs and the difference was amazing. -- http://improve-usenet.org/index.html If you have broadband, your ISP may have a NNTP news server included in your account: http://www.usenettools.net/ISP.htm Sporadic E is the Earth's aluminum foil beanie for the 'global warming' sheep. |
#17
Posted to sci.electronics.repair
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Any Panasonic VCR Experts In Here?
In article , Ron wrote:
On Jul 3, 4:40=A0am, "Arfa Daily" wrote: "nipperchipper" wrote in message ... "Ron" wrote in message ..= .. I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older one) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering about is the "arm" on the center post of the (newer) PV-V4540...what is that? PV-V4540 =A0head unit http://i126.photobucket.com/albums/p...IM002417-1.jpg PV-9450 head unit http://i126.photobucket.com/albums/p...IM002411-1.jpg PV-V4540 face http://i126.photobucket.com/albums/p...IM002414-1.jpg PV-9450 face http://i126.photobucket.com/albums/p...IM002413-1.jpg from the parts list pvv4540 uses the beliow listed upper cylinder head VEGS0427 =A0( A ) VEGS0428 =A0( B,C,D ) VEGS0429 =A0( E,F ) pv9450 uses VEHS0571 =A0( A ) VEHS0570 =A0( B,C ) VEHS0567 =A0( D,E ) not much help but swapping may not hurt Given that info, it's probably not going to work right. Hifi sound is critical of correct head performance, so if there are any specification differences between the head drums, there will likely be a problem. Well, that is an understatement. Put the head drum from the older working VCR into the newer one, there was no signal on the face plate for "HiFi". So I put it back into the - what was working unit - and NO HiIFi. Don't know what happened, but the newer VCR fried something in the older ones head drum. Now I have 2 Panasonics that don't work. Didnt the fact that they were two completely different model numbers on the heads and drums tip you off? |
#18
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Any Panasonic VCR Experts In Here?
In article , "Michael A. Terrell" wrote:
Ron wrote: Orlando huh? Wanna help out a neighbor? I would, but I'm closer to Gainesville these days. Orlando was 20+ years ago, and I've slowly moved North since then. So has half of Cuba. |
#20
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Any Panasonic VCR Experts In Here?
snip The upper drum(s) can only go on one way. It has a pilot hole for a guide and the screw holes are also slightly offset. Don't know what happened, but switching them fried something in either the units themselves, or in the upper drums. *Both* units with their original heads have video, but the audio is muddy. I cleaned both using the fingernail method you mentioned, followed up with paper and alcohol, no change. Oh well......... OK. Well the offsetting of the screw holes is what I had expected, so I really don't know what you can have done. I can't think of any way that either set of heads, let alone both, can have been damaged by simply swapping them between machines. Even if one set had much more 'robust' windings to take a higher bias current on record, they should at least have survived in the other machine. It's been a while since I did much work on VCRs as they have not been popular here for a couple of years now, but 'muddy' is not a description that I would normally have found a way of putting to a hifi sound track. Usually, this track has a tendency to drop out completely when the heads wear, and the machine reverts back to the linear sound track, which can be muddy if the A/S head is not properly aligned. You said before that you had altered the setting of the supply guide roller. Have you tried making sure that you have that back in exactly the right place ? As I think I pointed out earlier, correct recovery of the hifi sound track is critical of several factors. Arfa |
#21
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Any Panasonic VCR Experts In Here?
On Jul 4, 4:24*am, "Arfa Daily" wrote:
snip The upper drum(s) can only go on one way. It has a pilot hole for a guide and the screw holes are also slightly offset. Don't know what happened, but switching them fried something in either the units themselves, or in the upper drums. *Both* units with their original heads have video, but the audio is muddy. I cleaned both using the fingernail method you mentioned, followed up with paper and alcohol, no change. Oh well......... OK. Well the offsetting of the screw holes is what I had expected, so I really don't know what you can have done. I can't think of any way that either set of heads, let alone both, can have been damaged by simply swapping them between machines. Even if one set had much more 'robust' windings to take a higher bias current on record, they should at least have survived in the other machine. It's been a while since I did much work on VCRs as they have not been popular here for a couple of years now, but 'muddy' is not a description that I would normally have found a way of putting to a hifi sound track. Usually, this track has a tendency to drop out completely when the heads wear, and the machine reverts back to the linear sound track, which can be muddy if the A/S head is not properly aligned. You said before that you had altered the setting of the supply guide roller. Have you tried making sure that you have that back in exactly the right place ? As I think I pointed out earlier, correct recovery of the hifi sound track is critical of several factors. Arfa I never touched the roller guides on the older VCR that worked fine. All I did was remove the upper drum (or whatever it's called) and install it on my "newer" Panasonic. There was no HiFi audio icon on the newer unit with the older drum unit. So, I removed it, and reinstalled it on in the unit it came from and I now have muddy/humming audio. And vice-versa. |
#22
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Any Panasonic VCR Experts In Here?
In article , Ron wrote:
On Jul 4, 2:40=A0am, (GMAN) wrote: In article = ..com, Ron wrote: On Jul 3, 4:40=3DA0am, "Arfa Daily" wrote: "nipperchipper" wrote in message ... "Ron" wrote in message = m..=3D .. I have two Panasonic VCR's, model numbers PV-V4540 and PV-9450. They are almost idenical on the outside and very simular on the inside. The "newer" model - PV-V4540 - seems to have a head going bad from everything I've read. The PV-9450 works fine, but doesn't have the features that the PV- V4540 has. I would like to install the head unit from the PV-9450 (the older o= ne) in the PV-V4540 (the newer one). They look the same, but are they the same? And if I swap the headunits, will the alignment be the same? Here are pics of the head units. The one thing that I wondering abo= ut is the "arm" on the center post of the (newer) PV-V4540...what is that? PV-V4540 =3DA0head unit http://i126.photobucket.com/albums/p...IM002417-1.jpg PV-9450 head unit http://i126.photobucket.com/albums/p...IM002411-1.jpg PV-V4540 face http://i126.photobucket.com/albums/p...IM002414-1.jpg PV-9450 face http://i126.photobucket.com/albums/p...IM002413-1.jpg from the parts list pvv4540 uses the beliow listed upper cylinder he= ad VEGS0427 =3DA0( A ) VEGS0428 =3DA0( B,C,D ) VEGS0429 =3DA0( E,F ) pv9450 uses VEHS0571 =3DA0( A ) VEHS0570 =3DA0( B,C ) VEHS0567 =3DA0( D,E ) not much help but swapping may not hurt Given that info, it's probably not going to work right. Hifi sound is critical of correct head performance, so if there are any specificatio= n differences between the head drums, there will likely be a problem. Well, that is an understatement. Put the head drum from the older working VCR into the newer one, there was no signal on the face plate for "HiFi". So I put it back into the - what was working unit - and NO HiIFi. Don't know what happened, but the newer VCR fried something in the older ones head drum. Now I have 2 Panasonics that don't work. Didnt the fact that they were two completely different model numbers on t= he heads and drums tip you off? Just because something has a different model number, doesn't mean it won't work. Sometimes the same product can have an updated model number. That was the reason for my "Any Panasonic VCR Experts In Here?".....I took a chance, and it didn't work out.....oh well. Instead of criticizing what I did, give me an answer as to why it didn't work...besides they weren't the same model number. I wasnt criticizing you, I just was basically telling you it wasnt going to work, but you tried it anyways. they are completely different parts from two different series of chassies. I am sorry it didnt work out for you. Keep looking around at salvation army or thrift stores and you might find another one of those models. I see panasonics at the local Deseret Industries thrift stores all the time for $5. |
#23
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Any Panasonic VCR Experts In Here?
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#24
Posted to sci.electronics.repair
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Any Panasonic VCR Experts In Here?
On Fri, 4 Jul 2008 11:41:30 -0700 (PDT), Ron
wrote: On Jul 4, 12:35*pm, (GMAN) wrote: I am sorry it didnt work out for you. Keep looking around at salvation army or thrift stores and you might find another one of those models. I see panasonics at the local Deseret Industries thrift stores all the time for $5. That is my plan. Salvation Army, Goodwill, Craigslist, etc. About the only thing that could have gone wrong is that one of the hi-fi heads got damaged while you were swapping them. It's easy to bump one of the heads and break it. Did you try cleaning the heads after the swap? Did it at least fix the video problem? There's a slight chance that you need to adjust the head switching point. It was very critical on older hi-fi VCRs. Just removing and replacing the same head drum can be enough to throw it off. I don't know if newer Panasonics require an adjustment. I've found that video heads will usually work fine if they physically fit, and have the same number of heads. In a few rare cases, heads from different manufacturers can even be swapped. For example, in the 80's and early 90's Goldstar copied Panasonic's head mounting and electrical connections exactly. I fixed many Panasonics with heads salvaged from Goldstar VCRs. It worked out well because Panasonic VCRs lasted a long time and often had worn out heads. On the other hand, Goldstar VCRs usually broke long before the heads had any wear on them. Andy Cuffe |
#25
Posted to sci.electronics.repair
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Any Panasonic VCR Experts In Here?
"Andy Cuffe" wrote in message ... On Fri, 4 Jul 2008 11:41:30 -0700 (PDT), Ron wrote: On Jul 4, 12:35 pm, (GMAN) wrote: I am sorry it didnt work out for you. Keep looking around at salvation army or thrift stores and you might find another one of those models. I see panasonics at the local Deseret Industries thrift stores all the time for $5. That is my plan. Salvation Army, Goodwill, Craigslist, etc. About the only thing that could have gone wrong is that one of the hi-fi heads got damaged while you were swapping them. It's easy to bump one of the heads and break it. Did you try cleaning the heads after the swap? Did it at least fix the video problem? There's a slight chance that you need to adjust the head switching point. It was very critical on older hi-fi VCRs. Just removing and replacing the same head drum can be enough to throw it off. I don't know if newer Panasonics require an adjustment. I've found that video heads will usually work fine if they physically fit, and have the same number of heads. In a few rare cases, heads from different manufacturers can even be swapped. For example, in the 80's and early 90's Goldstar copied Panasonic's head mounting and electrical connections exactly. I fixed many Panasonics with heads salvaged from Goldstar VCRs. It worked out well because Panasonic VCRs lasted a long time and often had worn out heads. On the other hand, Goldstar VCRs usually broke long before the heads had any wear on them. Andy Cuffe My feelings and experience too, Andy. I really can't figure what he did wrong or what happened to bring the situation to the point of neither machine working. Arfa |
#26
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Any Panasonic VCR Experts In Here?
On Jul 7, 4:13Â*pm, Andy Cuffe wrote:
On Fri, 4 Jul 2008 11:41:30 -0700 (PDT), Ron wrote: On Jul 4, 12:35�pm, (GMAN) wrote: I am sorry it didnt work out for you. Keep looking around at salvation army or thrift stores and you might find another one of those models. I see panasonics at the local Deseret Industries thrift stores all the time for $5. That is my plan. Salvation Army, Goodwill, Craigslist, etc. About the only thing that could have gone wrong is that one of the hi-fi heads got damaged while you were swapping them. Â*It's easy to bump one of the heads and break it. Â*Did you try cleaning the heads after the swap? Â*Did it at least fix the video problem? Didn't bump the drum/head on anything. Had the VCR's sitting side-by- side. 4 screws, doesn't get any easier. And the heads were cleaned after the swap, before I even put a tape in. The video problem still remains on the newer unit, plus it now has the audio problem. The older unit has a fine picture, but it now has the *same* audio problem. (very muddy and choppy while playing in HiFi.) There's a slight chance that you need to adjust the head switching point. Â*It was very critical on older hi-fi VCRs. Â*Just removing and replacing the same head drum can be enough to throw it off. Â*I don't know if newer Panasonics require an adjustment. Is that something I can do with no special eqt? I've found that video heads will usually work fine if they physically fit, and have the same number of heads. Â* I don't see why it wouldn't work, then again, I'm not a VCR repairman. It's not a huge deal now, last Saturday I found a BRAND NEW Sony SLV- N55 (a better VCR anyway) for $8.00 at a Salvation Army! But, it would be nice if I could resolve the audio problem on the older Panasonic, if possible. |
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