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Television Standards Converters, Modulators etc Standards converters, modulators anything else for providing signals to vintage televisions. |
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10th Feb 2006, 5:16 pm | #21 | |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,820
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Re: 405 easy converter kit - does it make sense?
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I notice you've used board with pads rather than strips. What wire do you use for the interconnections, enamelled copper (like you'd use for coils and transformers) or something a bit more special? Nick. |
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10th Feb 2006, 5:27 pm | #22 | |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
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Re: 405 easy converter kit - does it make sense?
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yes, I use transformer wire. The soilderable kind of course and plastic spray to fix it. Kind regards Darius |
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10th Feb 2006, 5:54 pm | #23 |
Retired Dormant Member
Join Date: Dec 2003
Location: North London, UK.
Posts: 6,168
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Re: 405 easy converter kit - does it make sense?
For many years (before surface mount made it impossible) I used plain pinboard for prototyping. Just like veroboard but with no copper at all. I mount most components on pins and wired with a mixture of tinned copper and fine insulated wire. The wire I usually used was actually designed for wire wrapping. Sometimes I used a sort of pen with a reel of fine enamelled wire. I forget the name of this system. I often used to put a good solid 0V wire all the way round the edge of the board. This was very useful in video designs. Occasionally I used "colander ground plane" boards. These are like the one Darius shows but with a ground plane on the other side. This is mostly covered with solder resist which is easily scraped away to make a good 0V connection. These boards approximated a PCB with continuous ground plane. Very good for video and high frequency work.
In previous pictures I have also seen Darius use plain pieces of copper clad board. The circuit is assembled in mid air or holes can be drilled and counterbored to give isolated connections. This is an excellent high frequency technique. I don't like veroboard with copper strips. Whatever you use for prototyping, a PCB is really the only solution for a kit that may be built by relatively inexperienced people. The simplest PCBs, with just one copper layer, are fine for simple circuits. Double sided, ideally with plated through holes, would be ideal for Darius's converter but this costs a lot more than single sided and is difficult to etch at home. The Aurora converter uses a 4 layer PCB and is designed and built exactly as a professional design. One of the layers is a continuous ground plane. Small boards like this are not too expensive provided you order a fair quantity (25+, preferably 100+) and are not fussy about delivery time. I think Darryl paid something like $20 for each Aurora PCB. Enough of my ramblings. It's Darius's design and entirely his choice of PCB etc. |
10th Feb 2006, 6:38 pm | #24 | |
Octode
Join Date: Oct 2003
Location: Newbury, Berkshire, UK.
Posts: 1,770
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Re: 405 easy converter kit - does it make sense?
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WRT Darius's design, it looks a good alternative to the more expensive standards converters available, but I would echo previous comments. IMHO to get a reasonable take-up amongst those whose primary interest is in vintage video, a PCB would have to be provided. Ideally a full kit of parts should also be provided, but failing that it is vital to provide any components that are difficult to source. IMHO people simply will not buy a kit if there is even a smidgeon of a chance that some parts will be unattainable. Just by two pennorth. Well done Darius for making the effort – I really hope this project will be a success
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Chris |
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10th Feb 2006, 6:57 pm | #25 | |
Retired Dormant Member
Join Date: Dec 2003
Location: Solingen, Germany
Posts: 727
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Re: 405 easy converter kit - does it make sense?
Quote:
yes I agree. I don't like vero board with copper strips too. I think this depends in what you started with. This is definately nothing for a kit. I don't want to etch at home. The problem with multilayer is, if somebody destroies a hole there is no contact to the inner layers any more. I want to make it with one layer. This makes it easy to follow a wire with your eys to find mistakes. If you repair something without a layout (and schematic) it is much better to have only one layer. With two layers it is very difficult and multilayer no chance. My soft is able to generate a so called "ground polygon". Means it fills every space with ground. I used this with great success at the UVB. Kind regards Darius |
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