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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 26th Jun 2017, 10:37 am   #21
julie_m
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Default Re: DVD on 405 tv without converter?

Don't forget, you will still need a suitably-rated isolation transformer to power the TV if you go down this route.
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Old 1st Jul 2017, 1:15 am   #22
Graham G3ZVT
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Default Re: DVD on 405 tv without converter?

Quote:
Originally Posted by julie_m View Post
Don't forget, you will still need a suitably-rated isolation transformer to power the TV if you go down this route.
Yes, indeed.

I have since built this modulator.

http://www.earlytelevision.org/405_modulator.html

I'm also using the same ATI graphics card as Peter as the nVidia ones I initially used needed a computer with Windows XP.

I hope we get a few more trying this, the card cost £7 and the modulator parts came from my junk box, all but the two chips, at £10 for the pair.

So there you go, anyone with a computer with a PCI-e slot can have their own Ally Pally for about £20.
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Old 1st Jul 2017, 2:06 am   #23
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Default Re: DVD on 405 tv without converter?

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Originally Posted by Oliver35 View Post
I'd not restored a TV before, and bought a little Ferguson for £25 locally
Hi Oliver, the Cossor was my first restoration project too, but as I was a TV repair tech from 1971 to 1990 I wasn't without experience!
I never encountered a set with a round CRT, ion trap, or an energised loudspeaker during my day job, those attributes alone endeared the Cossor 916 to me.

An even better set of the same vintage would have been the HMV 1805
Why? Because it's the set that entertained me for the first six years of my existence, and it's got mains derived EHT!

The Aurora is a nice piece of kit but it's not the only way

With a PC you have unlimited access to digital video files, and something like Vidblaster adds a mixer telecines flying spot scanners, telerecording monoscopes, caption generators, etc. etc. All virtual of course, but no less convincing on the screen of your old set.
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Old 18th Jul 2017, 8:34 pm   #24
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Default Re: DVD on 405 tv without converter?

Well, my experiment in transferring a 405-line VHS recording to DVD wasn't met with success, although the sound is perfect throughout. No real surprise there.

This is the image I'm getting from the Regentone 194 (Plessey) set fed by a VHF L'l Dino modulator with the output direct from the DVD player. It looks like it might lock but adjusting the line hold control increases the chaos.
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Old 19th Jul 2017, 2:59 pm   #25
julie_m
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Default Re: DVD on 405 tv without converter?

VHS sort-of-works for 405 line signals because the recording is continuous in time, and blanking and sync pulses are represented directly as part of the recording. Whereas, an MPEG stream recorded on a DVD is framed to suit a broadcast standard. Only the active parts of each line are digitised, with the blanking and sync regenerated digitally during playback.

Your DVD recorder will be recording nearly 2/3 of the first 405-line line of the first field into the first 625-line line, ignoring any video signal during the 625-line horizontal flyback period; then recording the rest of the first 405-line line, the first 405-line horizontal flyback period and the beginning of the second 405-line line into the second 625-line line; again ignoring any video signal during the 625-line horizontal flyback period; then recording the end of the second 405-line line into the third 625-line line.

When played back, it will generate 625-line-style sync pulses after each line and field.
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