russt@zinfandel.UUCP (Russ Tremain) (06/14/85)
I recently purchased a Fisher stereo VHS VCR. In general, I am very happy with its performance, but I've noticed the record-length timer is non-linear. In other words, a half-hour recording at the begining of the tape is not equivalent in counter-units to a half-hour recording at the middle or end of the tape. (as the tape rolls, the counter units are longer with respect to time). Is this normal?
JCA@psuvm.BITNET (06/20/85)
Think about it for a minute the size of the hub on the tape changes as
you use tape. At the end of the tape the revolutions hold much more tape
than at the beginning.
seifert@hammer.UUCP (Snoopy) (06/24/85)
In article <433@zinfandel.UUCP> russt@zinfandel.UUCP (Russ Tremain) writes: >I recently purchased a Fisher stereo VHS VCR. In general, I am very happy >with its performance, but I've noticed the record-length timer is non-linear. > >In other words, a half-hour recording at the begining of the tape is not >equivalent in counter-units to a half-hour recording at the middle or end >of the tape. (as the tape rolls, the counter units are longer with respect >to time). > >Is this normal? That's what happens when the tape counter runs off the spool drive. As the tape runs, the diameter of the spool of tape changes, and the spool rpms change. *Real* VCRs, like the Sony SL-2700, run the tape counter off the signals recorded on the tape. The tape counter reads in hours/minutes/seconds, and is *correct*. I doubt if any VHS machines do this, since the tape has to come off the head for fast-wind, and you couldn't pick up the timing signals. Beta HiFi, the system that works. Snoopy tektronix!hammer!seifert
terryl@tekcrl.UUCP () (06/24/85)
>>I recently purchased a Fisher stereo VHS VCR. In general, I am very happy >>with its performance, but I've noticed the record-leng's oimer is non-linear. >> >>In other words, a half-hour recording at the begining of the tape is not >>equivalent in counter-units to a half-hour recording at the middle or end >>of the tape. (as the tape rolls, the counter units are longer with respect >>to time). >> >>Is this normal? >That's what happens when the tape counter runs off the spool drive. >As the tape runs, the diameter of the spool of tape changes, and >the spool rpms change. *Real* VCRs, like the Sony SL-2700, run >the tape counter off the signals recorded on the tape. The tape >counter reads in hours/minutes/seconds, and is *correct*. I doubt >if any VHS machines do this, since the tape has to come off the >head for fast-wind, and you couldn't pick up the timing signals. Yep, that's the only way to do it, using the timing signals on the tape. My NEC Beta Hi-Fi also has a REAL TIME COUNTER. Kinda handy to mark time indexes on the tape to say where something starts/stops.
raan@hp-pcd.UUCP (raan) (06/25/85)
>> I recently purchased a Fisher stereo VHS VCR. In general, I am very happy >> with its performance, but I've noticed the record-length timer is non-linear. >> In other words, a half-hour recording at the begining of the tape is not >> equivalent in counter-units to a half-hour recording at the middle or end >> of the tape. (as the tape rolls, the counter units are longer with respect >> to time). >> Is this normal? Yes. There are two (at least) basic methods for generating the tape counter reading. If your unit has a mechanical counter (like an odometer on a car) then you probably have method 1. If it is an electronic counter, then it may use either method, but your observation would indicate that it uses method 1. 1) The counter counts the revolutions of one of the tape reels. If it is the take-up reel, then as more tape winds on to the reel (causing it to thicken), each turn has a larger circumference and hence takes more tape (and therefore a longer time). If it is counting the source reel, then the same affect takes place in reverse and the times will get shorter as the tape progresses. 2) The counter counts the timing signals that are recorded on the tape. These would be consistant as the tape progresses, so you would not see any variation. This type of counter usually displays its count in terms of time elapsed, which is very useful. Most of the newer Sony machines do this. --- Raan Young (hp-pcd!raan) ~~~~~~~~~~~~~~~ hplabs ---->\ harpo ----> \ ----> >--!hp-pcd!raan microsoft ----> / textronix ---->/ ~~~~~~~~~~~~~~~
preece@ccvaxa.UUCP (06/26/85)
> I recently purchased a Fisher stereo VHS VCR. In general, I am very > happy with its performance, but I've noticed the record-length timer is > non-linear. ---------- I can't speak to VCRs, but this has generally been the case with audio tape decks, until recently. The counter is apparently dependent on the angular velocity of the reel rather than the linear velocity of the tape. A lot of the more sophisticated units now have real time displays, which are useful for more tasks. -- scott preece gould/csd - urbana ihnp4!uiucdcs!ccvaxa!preece
gnome@olivee.UUCP (Gary Traveis) (06/27/85)
> In article <433@zinfandel.UUCP> russt@zinfandel.UUCP (Russ Tremain) writes: > >I recently purchased a Fisher stereo VHS VCR. In general, I am very happy > >with its performance, but I've noticed the record-length timer is non-linear. > > > >In other words, a half-hour recording at the begining of the tape is not > >equivalent in counter-units to a half-hour recording at the middle or end > >of the tape. (as the tape rolls, the counter units are longer with respect > >to time). > > > >Is this normal? > > That's what happens when the tape counter runs off the spool drive. > As the tape runs, the diameter of the spool of tape changes, and > the spool rpms change. *Real* VCRs, like the Sony SL-2700, run > the tape counter off the signals recorded on the tape. The tape > counter reads in hours/minutes/seconds, and is *correct*. I doubt > if any VHS machines do this, since the tape has to come off the > head for fast-wind, and you couldn't pick up the timing signals. > > Snoopy > tektronix!hammer!seifert Actually, I know of at least two Hitachi VHS decks that have both tape-count (off the reels) and time count (updated in minutes and tenth minutes, I think) which runs from the capstan drive circuit. Both counters are independent and can be viewed and reset sepparately. My 9700 also has "search for 000 (tape counter)" and "search for beginning of record" which can be turned on and of individually. This is nothing new. The 9700 came out 4 years ago. "You want quality? Use a laser!" Gary
stv@qantel.UUCP (Steve Vance@ex2499) (06/28/85)
>>the spool rpms change. *Real* VCRs, like the Sony SL-2700, run >>the tape counter off the signals recorded on the tape. The tape >>counter reads in hours/minutes/seconds, and is *correct*. I doubt >>if any VHS machines do this, since the tape has to come off the >>head for fast-wind, and you couldn't pick up the timing signals. Is that how Beta does it? Some European company (Phillips?) has a scheme that measures the speed difference between the feeder and take-up hubs, and determines where you are on the tape based on that information. When you insert a tape, it moves it a couple of inches before loading it, to see where it is positioned. After that, it displays HH:MM:SS, to within about 30 seconds accuracy, no matter how the tape moves. I can't name any models available in the US which use this method, but it would work just as well for VHS as for Beta. -- Steve Vance {dual,hplabs,intelca,nsc,proper}!qantel!stv dual!qantel!stv@berkeley Qantel Corporation, Hayward, CA
gj@bubba.UUCP (06/29/85)
I have a Mitsubishi VHS deck. I believe the model number is HS-330UR.
It has a tape counter that is not linear and it also has a time
remaining feature. It takes about 1 minute playing to calibrate
. After that, if you punch a button, it will display the remaining
time accurate to within a minute. It also maintains the time accurately
during FF and REW. It has a bunch of other nice features and overall I am
quite pleased with it.
--
George Jenkins, COSI Texas, Inc., 4412 Spicewood Springs #801, Austin TX
78759 USA
uucp: {ihnp4,seismo,ctvax}!ut-sally!cositex!bubba!gj
at&t: (512) 345-2780uhclem@trsvax (07/01/85)
>... spool rpms change. *Real* VCRs, like the Sony SL-2700, run >the tape counter off the signals recorded on the tape. The tape >counter reads in hours/minutes/seconds, and is *correct*. I doubt >if any VHS machines do this, since the tape has to come off the >head for fast-wind, and you couldn't pick up the timing signals. My VHS Magnavox (Phillips) displays accurate time remaining. They do it the same way my Pioneer CT-9R cassette deck does it: They calculate the amount of tape left on the supply reel by the rotation rates of the supply vs. take-up reel. The VCR only gives it to you in :05 minute intervals, but the cassette deck has it down the the second and both are pretty close. You have to tell the unit when you are using T-160 tapes so that it can adjust the calculation, but it needed to know anyway so it could adjust tape tension. <The above opinions are mine, not my employers: IBM doesn't make VCR's.> "Thank you, Uh Clem." Frank Durda IV @ <trsvax!uhclem>
arcorp@utcsri.UUCP (Alias Research Corp.) (07/01/85)
> the spool rpms change. *Real* VCRs, like the Sony SL-2700, run > the tape counter off the signals recorded on the tape. The tape > counter reads in hours/minutes/seconds, and is *correct*. I doubt > if any VHS machines do this, since the tape has to come off the > head for fast-wind, and you couldn't pick up the timing signals. > > Beta HiFi, the system that works. > Snoopy > tektronix!hammer!seifert One bad thing about the SL-2700 (the REAL vcr) is that it resets the time counter every time you put in a tape. You have no choice in the matter. This "feature" means that if you want to take a quick look at, say, the beginning of another tape to see whats on it, then you lose your place on the time counter for the current tape. One of the best solutions to this whole problem is incorporated into high end RCA VHS decks. A friend of mine has a VKT-650, and it has the ability to display "Time Remaining" on the TV screen. All that one need do is place a tape into the machine and play it with the display switched on. At first, time remain is indicated as "--:--" Then, a minute and a half later, the actual time remaining appears as " 1:03" and gets updated as you play rewind and fast forward". There are motion lap counters that compare how fast the hubs are turning (angular velocity), and from that information an accurate time index is calculated. Having used his vcr for a couple of days of re-recording, I can attest to the accuracy of the time count. The time is given as hours:minutes, and he uses that number to index the locations of all programs on his tapes. It's so nice not having to rewind to the beginning to find out where a program is. Stephen Y. Trutiak (I Like LaserVision)
fred@varian.UUCP (Fred Klink) (07/03/85)
> >That's what happens when the tape counter runs off the spool drive. > >As the tape runs, the diameter of the spool of tape changes, and > >the spool rpms change. *Real* VCRs, like the Sony SL-2700, run > >the tape counter off the signals recorded on the tape. The tape > >counter reads in hours/minutes/seconds, and is *correct*. I doubt > >if any VHS machines do this, since the tape has to come off the > >head for fast-wind, and you couldn't pick up the timing signals. > > Yep, that's the only way to do it, using the timing signals on the > tape. My NEC Beta Hi-Fi also has a REAL TIME COUNTER. Kinda handy to mark > time indexes on the tape to say where something starts/stops. Really real VCR's like my Fisher VHS mark program start for you (what Fisher calls Automatic Program Search), so you just load the tape and FF to the program you segment you want. So there!
seifert@hammer.UUCP (Snoopy) (07/09/85)
In article <334@varian.UUCP> fred@varian.UUCP (Fred Klink) writes: >> >That's what happens when the tape counter runs off the spool drive. >> >As the tape runs, the diameter of the spool of tape changes, and >> >the spool rpms change. *Real* VCRs, like the Sony SL-2700, run >> >the tape counter off the signals recorded on the tape. The tape >> >counter reads in hours/minutes/seconds, and is *correct*. I doubt >> >if any VHS machines do this, since the tape has to come off the >> >head for fast-wind, and you couldn't pick up the timing signals. >> >> Yep, that's the only way to do it, using the timing signals on the >> tape. My NEC Beta Hi-Fi also has a REAL TIME COUNTER. Kinda handy to mark >> time indexes on the tape to say where something starts/stops. > >Really real VCR's like my Fisher VHS mark program start for you (what >Fisher calls Automatic Program Search), so you just load the tape and >FF to the program you segment you want. So there! Hate to break this to you, but the SL-2700 has indexes IN ADDITION TO the correct counter. Naaah Naaah! Note to whoever it was that was bragging about VHS having a readout with 5 minute resolution: get serious, eh? 5 minutes? That belongs in net.jokes. Okay, just to be fair, there *is* a feature that the 2700 lacks. It doesn't run UNIX. (Of course it's rather doubtful that any VHS models do either!) Snoopy tektronix!hammer!seifert
thoth@tellab3.UUCP (Marcus Hall) (07/10/85)
>> >*Real* VCRs, like the Sony SL-2700, run >> >the tape counter off the signals recorded on the tape. The tape >> >counter reads in hours/minutes/seconds, and is *correct*. >> >> Yep, that's the only way to do it, using the timing signals on the >> tape. My NEC Beta Hi-Fi also has a REAL TIME COUNTER. Kinda handy to mark >> time indexes on the tape to say where something starts/stops. > >Really real VCR's like my Fisher VHS mark program start for you (what >Fisher calls Automatic Program Search), so you just load the tape and >FF to the program you segment you want. So there! Real VCRs like the Sony SL-2700 do both! marcus hall ..!ihnp4!tellab1!tellab2!thoth
csdf@mit-vax.UUCP (Charles Forsythe) (07/10/85)
In article <1369@hammer.UUCP> seifert@hammer.UUCP (Snoopy) writes: >>> >the spool rpms change. *Real* VCRs, like the Sony SL-2700, run >>> >the tape counter off the signals recorded on the tape. The tape >>> >counter reads in hours/minutes/seconds, and is *correct*. I doubt >>> >if any VHS machines do this, since the tape has to come off the >>> >head for fast-wind, and you couldn't pick up the timing signals. >Hate to break this to you, but the SL-2700 has indexes IN ADDITION TO >the correct counter. Naaah Naaah! >Okay, just to be fair, there *is* a feature that the 2700 lacks. >It doesn't run UNIX. (Of course it's rather doubtful that any >VHS models do either!) >Snoopy Hate to break it to you, but cassette is a big lose in bandwidth anyway. Why settle for anything less than 2 inch broadcast quality with a TIMECODING track that can be fed to your 68000 based computer that DOES RUN UNIX. Seriously, I can't stand snobs :-). -- Charles Forsythe CSDF@MIT-VAX "The Church of Fred has yet to come under attack. No one knows about it." -Rev. Wang Zeep
brown@nicmad.UUCP (07/13/85)
In article <347@mit-vax.UUCP> csdf@mit-vax.UUCP (Charles Forsythe) writes: >Hate to break it to you, but cassette is a big lose in bandwidth anyway. >Why settle for anything less than 2 inch broadcast quality with a >TIMECODING track that can be fed to your 68000 based computer that DOES >RUN UNIX. Seriously, I can't stand snobs :-). I would rather settle for 1" C format with SMPTE time code. Why, because of the God awful problem with alignment that causes the color differences that can be seen every 17 lines (per field), when mis-adjusted and bright red. With 1" C, that problem doesn't exist and it is becoming the new standard of the TV industry. -- |------------| | |-------| o| JVC HRD725U Mr. Video | | | o| |--------------| | | | | | |----| o o o | | |-------| O| |--------------| |------------| VHS Hi-Fi (the only way to go) seismo!uwvax!astroatc!nicmad!brown ihnp4!nicmad!brown
gnome@olivee.UUCP (Gary Traveis) (07/15/85)
> >> >*Real* VCRs, like the Sony SL-2700, run > >> tape. My NEC Beta Hi-Fi also has a REAL TIME COUNTER. Kinda handy to mark > > > >Really real VCR's like my Fisher VHS mark program start for you (what > >Fisher calls Automatic Program Search), so you just load the tape and > > Real VCRs like the Sony SL-2700 do both! > > marcus hall > ..!ihnp4!tellab1!tellab2!thoth Oh yea! Well my incredibly REAL VCR goes out to the rental place and gets the TAPES too! It's not just AMAZING! It's AMAZINGLY AMAZING! :-) Ok, kiddies. Let's face it, you can compare features all day and still come up with the one main conclusion -- you can find decks that do everything, or nothing, in both Beta and VHS. If your parents and friends have VHS, get VHS. If your parents and friends have Beta, get Beta. If you want to record like the pros. Use a 3/4 or 1" deck! Real computers don't say "Abort,Ignore,Retry"! Gary
seifert@hammer.UUCP (Snoopy) (07/19/85)
In article <347@mit-vax.UUCP> csdf@mit-vax.UUCP (Charles Forsythe) writes: > >Hate to break it to you, but cassette is a big lose in bandwidth anyway. >Why settle for anything less than 2 inch broadcast quality with a >TIMECODING track that can be fed to your 68000 based computer that DOES >RUN UNIX. Seriously, I can't stand snobs :-). broadcast quality? ick! why not go with 70mm film? So the rental fees are a little higher, isn't quality worth it? 68000? You mean the VHS of micros? The 32032 blows it away. But as long as we're talking high-end, why not a Cray 2? Bavarian Beagle tektronix!hammer!seifert