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Television Standards Converters, Modulators etc Standards converters, modulators anything else for providing signals to vintage televisions. |
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3rd Dec 2009, 7:55 pm | #21 |
Nonode
Join Date: Jun 2008
Location: Coningsby, Lincolnshire, UK.
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Re: Whats the easiest way of getting 405 lines?
Hi
definately get an aurora!!! I put off buying one for about 2 years, now I have one, its fantastic! it mostly gets used on my TV22, its dead simple to use, and you don't need a video input all the time, since it has a test card programmed into it well worth their money, and don't take up much space! regards, Lloyd. |
3rd Dec 2009, 10:12 pm | #22 |
Dekatron
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Re: Whats the easiest way of getting 405 lines?
A simple RF signal generator modulated with a 400hz tone will produce some nice bars on the screen..... It is what I used in the beginnng.
Sean
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8th Dec 2009, 8:48 am | #23 |
Octode
Join Date: Jun 2006
Location: St Osyth, Nr Clacton, Essex, UK.
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Re: Whats the easiest way of getting 405 lines?
Here are my thoughts on getting started on 405, in a step-by-step and learning fashion (for what they’re worth!).
I’d start by building a simple feedback oscillator using a reasonably high ft transistor. Biased to conduct, a coil in the base circuit of maybe 5 turns and a couple of turns in the collector should make it sing nicely. Not knowing the channels required, some experimentation is needed – say twiddling a tuning trimmer and/or squeezing or separating the coil turns. The TV should show a huge peak signal when the frequency is about right. Then I’d put a carbon-granule microphone in series with the supply. Whistle into it. (It provides amplitude modulation). Bars should appear on the screen. At this stage I’d probably feed a 625 line signal into it – a single diode should provide some modulation. Obviously the line stage won’t lock but at least some moving images should result. A second option is to build a signal+sync combiner. Then a simple logic counter can generate a line sync and some bars. You could even build a 1, 2, 4, 8 D-to-A convertor to make some nice grey-scale bars. As an alternative to the oscillator, you could try to get hold of an RF modulator suitable for band 1 or band 3. In fact, I discovered a bag at the weekend labelled “Rediffusion modulator” which you’re welcome to and which I’m sure someone round here could tell you how to press into service. Some ideas which I hope you find useful and good on yer for wanting to start in a learning way. Graham |
10th Dec 2009, 12:08 pm | #24 |
Hexode
Join Date: Apr 2006
Location: Medway towns, Kent, UK.
Posts: 271
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Re: Whats the easiest way of getting 405 lines?
I've only got 1 405line TV but the aurora makes sense, it gives you full flexibility to watch what ever you like
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"Oh yes I love television, all those wiggly lines"! |
10th Dec 2009, 12:33 pm | #25 |
Nonode
Join Date: May 2005
Location: Godalming, Surrey, UK.
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Re: Whats the easiest way of getting 405 lines?
Hello Julie,
I managed to borrow an Aurora from a forum member to get my Bush TV22 working but that's got to go back now, so I've ordered my own from Crowthorne Tubes. The next batch of six is arriving from the USA next week, only one is left so if you decide to get one then order it now. The estimated price is £166, which is expensive, but the Aurora does work very well. http://www.crowthornetubes.com/radios.htm Howard |
11th Dec 2009, 5:06 pm | #26 |
Dekatron
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Re: Whats the easiest way of getting 405 lines?
£165 Howard, I reckon that is quite cheap considering the import duty and VAT. I'm sure I paid a bit more than that when I purchased mine from the States a while ago now. Worth twice the price..Regards, John.
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11th Dec 2009, 5:15 pm | #27 |
Retired Dormant Member
Join Date: Dec 2003
Location: North London, UK.
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Re: Whats the easiest way of getting 405 lines?
List price is $230, about £144 at current £/$ rates. You would be very lucky to get away with £20 for VAT, duty and handling fees. £30 seems nearer most folks experience.
Consumer electronics is only cheap when made in very large quantities. Aurora is made in batches of less than 100. The price is a bargain for what it does - a complete* zero hassle "plug and play" solution for running your 405 tellies. *You need to provide a cheap "wall wart" power supply |
11th Dec 2009, 6:39 pm | #28 |
Retired Dormant Member
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Location: Westbury, Wiltshire, UK.
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Re: Whats the easiest way of getting 405 lines?
My Aurora came to just under £190 all in when the pound was on the floor. It was still money well spent.
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11th Dec 2009, 6:49 pm | #29 |
Dekatron
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Location: Gateshead, Tyne and Wear, UK.
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Re: Whats the easiest way of getting 405 lines?
Hi John And Jeffery,
The Aurora is an absolute bargain, there nothing on the market to touch it. Even better when one considers that the five channel modulator is part of the deal. It's worth bearing in mind that my first attempt at building standards converters was way back in the mid 1980s and the costs to build them was in the order of four figures. DFWB. |
13th Dec 2009, 7:06 pm | #30 |
Dekatron
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Location: Kilmarnock, Ayrshire, UK.
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Re: Whats the easiest way of getting 405 lines?
Hi.
The Aurora is the best converter you can buy, I have two NTSC 405 line converters and an old multistandard one, I also had two mono 405 line converters that have been passed on. These converters are "cheap" when you consider the technology used and the fact they are made on tiny productiion runs. The quality of manufacture is excellent and the results are every bit as good as was the last of the broadcast converters. Any serious collector should have one or two or three!! No collusion with Darryl here but ever so satisfied. Cheers Trevor
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16th Dec 2009, 7:52 pm | #31 |
Rest in Peace
Join Date: Jul 2006
Location: Somerset, UK.
Posts: 2,356
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Re: Whats the easiest way of getting 405 lines?
I have two !
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4th May 2010, 8:43 am | #32 |
Pentode
Join Date: Feb 2006
Location: East London, UK.
Posts: 231
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Re: Whats the easiest way of getting 405 lines?
Hi Julie ,
Check your PM's for info about my modulator that i offered if you're still interested . Alan. |
5th May 2010, 12:35 pm | #33 |
Hexode
Join Date: Feb 2008
Location: Sydney, Australia
Posts: 356
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Re: Whats the easiest way of getting 405 lines?
There is only one problem with buying an Aurora, you will be so impressed you will probably be inclined start hunting for more 405 T.Vs.
Victor. |
5th May 2010, 1:10 pm | #34 |
Heptode
Join Date: Apr 2003
Location: Rugby, Warwickshire, UK.
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Re: Whats the easiest way of getting 405 lines?
Yes, I'd fully agree with that statement!!
Greg
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Greg BVWS committee chairman Last edited by Dave Moll; 5th May 2010 at 5:56 pm. Reason: unnecessary quote of preceding post removed |
5th May 2010, 9:03 pm | #35 |
Dekatron
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Location: Kilmarnock, Ayrshire, UK.
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Re: Whats the easiest way of getting 405 lines?
Hello again Julie.
Of course I would recommend buying an Aurora but with cash flow etc not everyone could afford one even myself now I have to watch the pennies. I can copy tapes for you onto VHS or Beta to get you started so PM me if interested.
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28th Aug 2010, 2:08 am | #36 |
Heptode
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Location: Ware, Hertfordshire, UK.
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Re: Whats the easiest way of getting 405 lines?
Hi Julie,
a few years ago I designed a very simple 405 line pattern generator. It is very small and cheap to make and produces proper 405 line interlaced patterns (at a very slightly lower than standard line and frame rate) using a PIC chip. I've never published this design by the way, but you are welcome to it. I should have enough bits to build one. However you will still need a modulator. I have made these in the past using David Looser's design as a basis but eliminating the crystal and using standard TOKO coils. Cheers Andy BTW if anyone else on the forum is interested in building my pattern generator I can publish it on another thread.
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28th Aug 2010, 3:40 pm | #37 |
Retired Dormant Member
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Re: Whats the easiest way of getting 405 lines?
I would be interested in that if you are happy to post the info!
Brian |
28th Aug 2010, 8:06 pm | #38 |
Dekatron
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Location: W.Butterwick, near Doncaster UK.
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Re: Whats the easiest way of getting 405 lines?
I paid mega money years ago and bought the "Dinosaur" ,made by D.Grant BBC.Superb mind.
David |
28th Aug 2010, 10:05 pm | #39 |
Dekatron
Join Date: Sep 2006
Location: Kilmarnock, Ayrshire, UK.
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Re: Whats the easiest way of getting 405 lines?
Hi.
Although the "dinosaur" was good in its time it really isn't in the league of the Aurora. The Aurora is far more cost effective and does not have the artefacts of the older designs. I have been looking at the thread and wonder if Julie is still watching what's going on as I don't see any further replies. I hope she hasn't given up as it's good to see the lasses on here too. I have had no contact per post 35!
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29th Aug 2010, 9:52 am | #40 |
Nonode
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Location: Western Lake District, Cumbria (CA20) - UK
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Re: Whats the easiest way of getting 405 lines?
Julie last logged in to the forum on 19th March so it would appear that she is an infrequent visitor.
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Brian |