6th May 2018, 6:03 pm | #141 |
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Have you fitted the adjustable core inside the width coil? As PJL suggests, you now need a decent signal. John.
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6th May 2018, 9:56 pm | #142 |
Octode
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
The problem now, with the signals side of things, is that you are facing way too many unknowns.
You have a TV with unknown faults You have a home built modulator which is untested Using a PC to convert to 405 is unlikely to yield the correct signal without a lot of experimentation. You don't have a 'scope to check the 405 output from the PC to see if it's even close to what it should be. Don't get me wrong, building your own modulator and using the PC is a great additional part of the project, but unless you can be sure that it's all working perfectly, you can hardly use it to fault find the TV! All the best Nick |
7th May 2018, 12:37 pm | #143 |
Hexode
Join Date: Apr 2016
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Hi John, yes the core has been fitted inside the coil.
Hi Nick, yes you're right I am very unprepared at the moment! I really should invest in a scope if I'm looking to get this project done and undergo any others in the future, I've had my eye on one for a while actually. I was under the impression that I could just plug an old digibox into the composite connectors on the modulator and it would convert it into a 405 line RF signal. Is this not the case? Peter |
7th May 2018, 1:58 pm | #144 | |
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Quote:
You can use a PC with a suitable video card (and software of course) for converting to 405 and then connect your modulator to the converted output for the TV. At the moment I think you have too many 'unknowns'!
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7th May 2018, 2:05 pm | #145 |
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
No, that's not going to work -- the modulator will still need to be fed with a 405-line signal. The output of a digibox will be 625-line.
You will need to invest in an Aurora standards converter (just search this forum) or else have a computer with a suitable graphics card that can be programmed for random resolutions and timings. Windows now has support for mode lines, which have always been used by the display system of most Unix variants including Linux and BSD since forever to set the video timings. (Different Unix workstations could have monitors with different resolutions and scan rates.) If you have the right graphics card and the right software, you can enter a mode line that will produce a 405-line output. You will then need a small additional circuit (we're talking postage-stamp size piece of breadboard; one transistor and a handful of resistors) to create a composite signal from the separate HSYNC, VSYNC and video lines. It's all just a forum search away .....
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7th May 2018, 2:11 pm | #146 |
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
http://www.tech-retro.com/Aurora_Des...Converter.html
Here's the UK supplier: https://www.crowthornetubes.co.uk/ Lawrence. |
7th May 2018, 2:24 pm | #147 |
Octode
Join Date: May 2003
Location: Belper Derbyshire
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
I bought mine from Crowthorne tubes via their EBay shop a few years ago. M
Christopher Capener
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Interests in the collection and restoration of Tefifon players and 405 line television |
7th May 2018, 2:35 pm | #148 |
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Yes so did I and a very good investment it was as well!
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7th May 2018, 4:16 pm | #149 |
Octode
Join Date: May 2003
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Yes well worth the money. What with built in test card C and switchable to all band I and band III frequencies as well as small size and simple operation I cannot fault it. I have the excellent Domino converter but this has been sidelined since I bought the Aurora converter.
Christopher Capener
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Interests in the collection and restoration of Tefifon players and 405 line television |
7th May 2018, 5:31 pm | #150 |
Hexode
Join Date: Apr 2016
Location: Yeadon, West Yorkshire, UK.
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Fair enough, I'll order myself an Aurora converter, I'll just have to beg on my knees for some overtime for a while!
Peter |
7th May 2018, 7:01 pm | #151 |
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
The beauty of the Aurora is that it will just work. In the absence of a video input it will generate a standard test card so once you've set the output channel to match your TV, all you do is power it up (you will need a separate power supply for it...9V at 1 amp will do).
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7th May 2018, 8:09 pm | #152 |
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Location: Newcastle upon Tyne, Tyne & Wear, UK.
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Hi, If you can cadge a very old VCR with a 405 recording that may provide a signal source, assuming it has a band 1 modulator
Ed |
7th May 2018, 10:21 pm | #153 |
Octode
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Due to it's tiny size and low price, the Aurora implies that the job of converting 625 to 405 is trivial. It's only due to some amazing modern technology that this is possible.
Back in the late 1960's, it took a double wardrobe sized piece of equipment full of discrete components to do the job. It must have cost thousands and taken a team of people to develop. 25 years ago, when I re-discovered my interest in 405 TV's, an affordable standards converter was the holy grail. Various dedicated people came up with solutions using available technology at the time. Before cheap FPGA chips came along, it was a very hard job indeed! So we should all worship at the feet of the Aurora and marvel at the amazing piece of kit that we have access to! Using an old PC wasn't feasible 25 years ago: they just were not fast enough. It is now practical, however, if you have sufficient computer skills. Peter, getting an Aurora will make getting your TV working correctly much more likely. Once it is working though, it would be good to continue to experiment with the PC conversion method and your home built modulator. All the best Nick |
8th May 2018, 8:33 am | #154 |
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
You will not be disappointed with an Aurora, it is an excellent product.
Just connect it to your aerial socket and you will have test card 'C' and a test tone. Once you have a picture of sorts, the on screen results will allow you to see the faults and address them. Once the set is working properly, just connect a DVD player or freeview box to the Aurora & enjoy! Mark |
11th May 2018, 1:48 pm | #155 |
Hexode
Join Date: Apr 2016
Location: Yeadon, West Yorkshire, UK.
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
I've received the Aurora today in one piece and I've just been reading the quick start guide and there's a few things I've flagged up. Firstly it says I need a 75 Ohm coaxial cable. I have some cable of the good quality brown type but I'm not sure about measuring the impedance. Secondly it says a transformer should be used if the chassis is connected to one of the AC lines, which mine is, any particular transformer?
Peter |
11th May 2018, 5:04 pm | #156 |
Octode
Join Date: Jan 2009
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
The brown coax is fine although you may want to find something a little more flexible in a premade length for everyday testing.
Personally never used a transformer with any of my sets, certainly its fine on any Ekco sets providing you make sure the mains two pin plug is always inserted the correct way around, I tend to mark the plug indicating the live pin, with the same on the chassis.
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Stephen _________"It`s only an old telly" ___ |
11th May 2018, 7:47 pm | #157 |
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
A live chassis set of course will have (should have) its aerial socket isolated to the outside world, so its worth checking any isolating capacitors are in order and any other insulation is as the manufacturer intended, for example the way the aerial socket is mounted on paxolin away from the chassis. You never know with old stuff whether someone less informed has been messing.
The aurora will generally be isolated (floating) to earth any how but i did once have a batch of wall-warts from CPC which had the 0V secondary connected to the mains earth; they were intended as laptop supplies though it wasn't stated as such.
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Kevin |
11th May 2018, 8:08 pm | #158 |
Hexode
Join Date: Apr 2016
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Thanks for the advice thus far I now have a signal on the screen although I can't get it to fill the screen horizontally. The focus control is not doing much and the picture width coil, although working doesn't make much of a difference.
Peter |
11th May 2018, 8:48 pm | #159 |
Heptode
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Hi Peter,
The line timebase is running at half the correct frequency, hence two pictures side by side. Onece you get it running at the right speed the EHT and width will be in the right ball park. The fault will be in the line oscillator. Cheers Andy
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11th May 2018, 9:01 pm | #160 |
Heptode
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Re: First TV Project - Ekco TCG316 - Any Advice Appreciated
Hi again Peter,
I also wanted to encourage you at this stage. This is a great result for a first picture Cheers Andy
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