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Television Standards Converters, Modulators etc Standards converters, modulators anything else for providing signals to vintage televisions.

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Old 14th Nov 2018, 9:42 pm   #1
FERNSEH
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Default JVC 7700EK VCR 1980. 405 line recording.

A good friend has asked me to record 405 line television on VHS tape.
We took a chance and inserted a pre-recorded cassette into a JVC HR7700EK, a machine that has not been used since 1996. Apart from the usual cassette loading problems the machine works perfectly. This will be the chosen machine for the 405 line recordings.
The HR7700 is similar to the Ferguson 3V23.

DFWB.
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Old 15th Nov 2018, 10:20 am   #2
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Default Re: JVC 7700EK VCR 1980. 405 line recording.

I too have just been given a Ferguson 3V23 which has been used to play back 405 line recordings. One such recording is, I am told, inside the machine which I look forward to playing. In ignorance, I was under the impression that only earlier ie mechanical VCR's could be used

From an earlier post, I believe that it is not possible to digitally record such 405 line recordings to use as a master. Not yet tried, I wonder if a combined VCR/DVD recorder might be tricked so that the visual loss when back to back video tape recording can be minimised.

Of course, many "old school" television recordings are available from the BBC on DVD or through Freeview/Web "DAVE" equivalents which can be held on HDD after which a Aurora will complete the loop.

Last edited by simpsons; 15th Nov 2018 at 10:35 am. Reason: update
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Old 15th Nov 2018, 11:39 pm   #3
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Default Re: JVC 7700EK VCR 1980. 405 line recording.

Quote:
Originally Posted by simpsons View Post
I too have just been given a Ferguson 3V23 which has been used to play back 405 line recordings. One such recording is, I am told, inside the machine which I look forward to playing. In ignorance, I was under the impression that only earlier ie mechanical VCR's could be used
In theory a VHS recording and playback system shouldn't care what line standard it is processing particularly as 405 and 625 share the same frame rate and therefore drum speed, in practice however machines tended to get too clever, and started to digitally clean up the sync pulses and be overzealous with drop-out correction which meant it basically got totally confused by the unexpected line rate.
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Originally Posted by simpsons View Post
From an earlier post, I believe that it is not possible to digitally record such 405 line recordings to use as a master.
It must be possible, and a lot simpler than 625, no colour to worry about! But nothing readily available as far as I know.
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Originally Posted by simpsons View Post
Not yet tried, I wonder if a combined VCR/DVD recorder might be tricked so that the visual loss when back to back video tape recording can be minimised.
Many have tried and failed to record 405 on a DVD recorder, there is a fundamental reason why but I have forgotten the details.
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Of course, many "old school" television recordings are available from the BBC on DVD or through Freeview/Web "DAVE" equivalents which can be held on HDD after which a Aurora will complete the loop.
But if you think about it there is a wealth of material originally made in 405 ready digitised and available on Youtube Vimeo etc. and that's why a few of us are keen to popularise the method of using a PC graphics card to output a 405 line signal directly, It's based on a project that was announced in this forum 12 years ago under the name FotH-TV and has lain dormant until I rediscovered it two years ago, and realised it nolonger had to be a geeky Linux project.

https://www.vintage-radio.net/forum/...d.php?t=130716
https://www.youtube.com/watch?v=Q9b7_x0g0uM
https://www.youtube.com/watch?v=ahzdx4KgWBg
http://www.nostalgiatech.co.uk/Baird%20240%20lines.htm
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Old 16th Nov 2018, 2:05 am   #4
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Default Re: JVC 7700EK VCR 1980. 405 line recording.

I have the AKAI version of this machine, the VS-10. Needs a new VFD display driver board otherwise it works fine. Built like a tank.

Fivos
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Old 16th Nov 2018, 9:57 am   #5
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Default Re: JVC 7700EK VCR 1980. 405 line recording.

Thank you Rambo1152 for the very helpful details posted. By bringing together the various iterations on the use of a computer based sourced material you have given me food for thought.

I, for one, have tended to stear clear of using my pc because it is used in an office environment. I do though have good laptop, an ASUS X555L. I wonder if this can do the job?

Reading between the lines, no pun intended, I see though it is necessary to switch between the dsub output and a "working" screen which, as an IT novice, can be done by the press of a dedicated button #F18.

A lot to digest me thinks and should the IT buffs out there have a view on my proposals please comment. Warts and All!!
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Old 16th Nov 2018, 10:56 am   #6
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Default Re: JVC 7700EK VCR 1980. 405 line recording.

Moving on, I do have an HDMI to composite converter which is being used to feed a plasma screen used by my daughter in her bedroom. As an aside, I am sure she switches the TV on to heat the room.

From posts here, this may well be a low cost simple for me, anyway, to achieve greater entertainment than re running The Dambusters etc. DVD's.

When I first used the HDMI converter, I did think resolution was not quite as good as the source which is important to get the best out of the larger screen dual standard TV's which I have.

Whilst test cards might look similar on both 405 and 625 displays, it is when playing moving images that any loss detail becomes important, especially where the scene is panoramic.

Chris
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Old 16th Nov 2018, 11:42 am   #7
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Default Re: JVC 7700EK VCR 1980. 405 line recording.

Quote:
...it is when playing moving images that any loss detail becomes important, especially where the scene is panoramic.
I wish someone had told that to whoever designed the digital projectors at most cinemas I've been to recently.
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Old 16th Nov 2018, 1:42 pm   #8
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Default Re: JVC 7700EK VCR 1980. 405 line recording.

I use a Mitsubishi HS-M60V (http://andydoz.blogspot.com/2014/11/...ding-belt.html) , which I presumed was far to new to record 405 material. It worked very well indeed.

Due to the bandwidth of VHS, pictures appear to be very good indeed on 405, as almost all of the bandwidth for 405 is available.

Tapes need to be kept spotless though, as the drop-out compensator won't!
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Old 17th Nov 2018, 10:03 pm   #9
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Default Re: JVC 7700EK VCR 1980. 405 line recording.

I found using a 3V29 to record and play 405 tapes, that the drop out compensator got in the way on playback. This caused a 'ghost' image about a third of the way across the screen. I seem to recall (I would need to look at the circuit again) that shorting out the delay line for the DOC cured the problem. 625 tapes really did need the DOC to be working though as the dropouts were very obvious.

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