Plunging right in - the first step

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Plunging right in - the first step

Postby NutmegCT » Sat Feb 23, 2008 1:02 am

I've decided to make my first televisor, using the Handbook instructions and Club parts.

Per the Handbook Chapter III, I'll need:

1. Wooden base - I'll build when the parts arrive.
2. A pre-drilled disc (available from the club shop)
3. Cassette motor (available from the club shop)
4. 12 Volt Power Supply (already have this)
5. Motor drive electronics (I assume this is a club PCB)
6. LED cluster as a light source (I'll use the Handbook guide)
7. A not too small magnifying glass (already have)
8. LED drive electronics (I assume this is a club PCB)

So I'll order the 12" 1.5 turn spiral disc, the cassette motor, the gears wheels, the motor and LED PCB's from the Club shop as listed on p2 of the newsletter. I don't know what the gear wheels are for, but I assume I'll need them. I'm also assuming the motor comes with some type of hub on which to mount the disc.

If anyone sees something I should add to the club shop order, please let me know.

As I don't have an email address for V.R.Brown, I'll use the post to mail him to find the total of the order including postage, wait for the reply, then mail my payment and await arrival.

Thanks all.
Tom
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Postby Klaas Robers » Sat Feb 23, 2008 4:59 am

Try Vic at nbtv.org I guess it works.

May be it is not a bad idea to order one or two of the Club CDs. They give you a stable source of more than perfect video signals, with sound.
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Postby NutmegCT » Sat Feb 23, 2008 6:32 am

Klaas - thanks so much for your help. I've tried the vic at nbtv.org and victor at nbtv.org addresses.

Both give "no such user" error messages from the server.

Tom
edit 4:15pmEST. corrected domain name.
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Postby DrZarkov » Sat Feb 23, 2008 8:19 am

Strange. That's exactly the e-mail which is given at the nbtv-website. I've contacted him before under this adress, with success.
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Postby NutmegCT » Sat Feb 23, 2008 10:30 am

It'll work out. I had problems connecting to the forum again this afternoon. First, server timed out for several attempts. Then, another of those pesky "you have been banned" issues I've had before, which has since resolved itself.

Thanks.
Tom
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Postby acl » Sat Feb 23, 2008 6:47 pm

1. Wooden base - I'll build when the parts arrive.
2. A pre-drilled disc (available from the club shop)
3. Cassette motor (available from the club shop)
4. 12 Volt Power Supply (already have this)
5. Motor drive electronics (I assume this is a club PCB)
6. LED cluster as a light source (I'll use the Handbook guide)
7. A not too small magnifying glass (already have)
8. LED drive electronics (I assume this is a club PCB)

So I'll order the 12" 1.5 turn spiral disc, the cassette motor, the gears wheels, the motor and LED PCB's from the Club shop as listed on p2 of the newsletter. I don't know what the gear wheels are for, but I assume I'll need them. I'm also assuming the motor comes with some type of hub on which to mount the disc.

If anyone sees something I should add to the club shop order, please let me know.

Tom,

Some clarificatins needed. If you use club PCBS these are slightly different circuits from in the handbook so use the boards and follow Klaas's instructions and you will be OK.

You only need a standard disk with 32 holes the 1.5 disk is for building the combined monitor/ camera in order to keep the picture the right way round.

Some people use a gear train between the motor and the disk to give smoother motor control but from experiance you can get away with direct drive to the disk. Also a single gearwheel is required in order to
connect the motor to the disk. Check with Vic to see if this is fitted to the clubs disks.


Please photograph and video if possible each stage of assembly so we can produce a video.

Regards Chris Lewis
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Postby DrZarkov » Sat Feb 23, 2008 7:01 pm

For making the sync-circuit you should order the 4046 from the club-shop, too. There are many substitutes available, but those are very often not working for our purposes. Here in Germany it was not possible to get the "original" 4046 just in a shop. The gear-wheels are not needed, they are used as a hub for the motor.
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Postby Viewmaster » Sat Feb 23, 2008 7:31 pm

acl wrote:
You only need a standard disk with 32 holes the 1.5 disk is for building the combined monitor/ camera in order to keep the picture the right way round.


But this 48 hole disk can be used just for a NBTV without any camera component, as the club shop doesn't advertise a 32 hole disk.
The 48 hole disk is perfectly OK for a beginner to use and it's relatively cheap!
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Postby Steve Anderson » Sat Feb 23, 2008 7:50 pm

DrZarkov wrote:There are many substitutes available, but those are very often not working for our purposes.


A word of caution to all, especially newcomers regarding logic chips of the type used in the current designs. The current designs published use a 12V power supply (or thereabouts) the 4046 chips should be typemaked HEF4046, MC14046, CD14046 and so on. The letters at the beginning only denote the manufactuer. Otherwise there is no difference between them and should work equally well.

This is a requirement of the military industry that at component level everything is at least second-sourced, i.e. more than one company makes an identical product. So if one company goes out of business, there's still a supply from elsewhere. Philips might develop a chip (as they did with the whole original 4000 series) but then they have to share the information with Motorola, STM and a whole bunch of others, otherwise the military just won't purchase equipment with then in. And that's big business.

For these designs they must not contain within the type number the letters 'HC', 'AC', 'HCT' or 'ACT' as these will go 'pop' at 12V, their maximum voltage is 6V, usually used at 5V. This is especially true if preceeded by '74'. These are from a different logic family and although functionally identical, the fabrication process whilst increasing their speed, reduces their supply voltage range. Speed is not an issue in these applications. If in doubt send me a PM, e-mail or ask a question within the forum.

Steve A.
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Postby NutmegCT » Sun Feb 24, 2008 12:16 am

I'm sifting through all the above. Especially as I have no electronics background, this project will be an interesting challenge.

One quick thing - Chris mentions: "You only need a standard disk with 32 holes the 1.5 disk is for building the combined monitor/ camera in order to keep the picture the right way round."

I don't see a 32 hole disk available in the Newsletter's Club shop parts list. I see only the 48 hole 1.5, and at the bottom "larger Nipkow disks (see text)".

Does the club have a standard 32 hole disk for purchase? I want to do this with Club parts as recommended in the Handbook.

Also, DrZarkov writes: "The gear-wheels are not needed, they are used as a hub for the motor."

So the motor will come with the appropriate way to mount and/or drive the disc? Perhaps if there were a picture of the Club parts (motor and disc) "in place" it would be helpful?

Thanks.
Tom
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Postby DrZarkov » Sun Feb 24, 2008 2:28 am

I used my own motors from old tape-recorders. They all had a kind of hub, some more usable, some less. I'm using the club-disc in one of my televisors, too. It is really no problem with the 48 holes. You just need the 32 starting from the outside, the inner 16 holes are not needed and simply covered by a mask. Or even easier, just use some black tape to close them. That is really not a problem at all.
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Re: Plunging right in - the first step

Postby gary » Sun Feb 24, 2008 10:54 am

NutmegCT wrote:I've decided to make my first televisor, using the Handbook instructions and Club parts.

Per the Handbook Chapter III, I'll need:

1. Wooden base - I'll build when the parts arrive.
2. A pre-drilled disc (available from the club shop)
3. Cassette motor (available from the club shop)
4. 12 Volt Power Supply (already have this)
5. Motor drive electronics (I assume this is a club PCB)
6. LED cluster as a light source (I'll use the Handbook guide)
7. A not too small magnifying glass (already have)
8. LED drive electronics (I assume this is a club PCB)

So I'll order the 12" 1.5 turn spiral disc, the cassette motor, the gears wheels, the motor and LED PCB's from the Club shop as listed on p2 of the newsletter. I don't know what the gear wheels are for, but I assume I'll need them. I'm also assuming the motor comes with some type of hub on which to mount the disc.

If anyone sees something I should add to the club shop order, please let me know.

As I don't have an email address for V.R.Brown, I'll use the post to mail him to find the total of the order including postage, wait for the reply, then mail my payment and await arrival.

Thanks all.
Tom


I recently purchased some club shop material all via email and paypal (see thread "NBTVA Newsletter Back issues? - Easy peasy" and thoroughly recommend this procedure for all purchases. I didn't use vic@nbtv.org since I had vic's personal address in my address list but I have since confirmed that vic@nbtv.org is up and the one to use.

Unfortunately the club motors do not come with special hubs for the discs. The plastic gears are a push-on fit to the (approx.) 2mm shaft. The discs currently available have a hole in the centre the same size as the motor shaft, so again the gear can be used. People use 'Evostick' glue to fix them to the plastic disc.

The disks I bought from the club were a previous, non-laser cut, version which have a 6mm centre hole. The club shop had brass fittings hubs, very nicely made, to suit this 6mm (o.d.) with a i.d. to suit the club motors. Apparently the club still has some of these but you would then need to drill a 6mm hole in the new disks.

The advantage of using a 48 hole disk is that it will work as a 32 line monitor now and if you get roped in (likely) you can then use it as a camera/monitor disk later. However, you will need to make a mask for best results.
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Postby Steve Anderson » Sun Feb 24, 2008 4:26 pm

NutmegCT wrote:Especially as I have no electronics background, this project will be an interesting challenge. Tom


Another tip to newcomers....if you haven't already, learn to solder! This is an essential skill and although looking simple, it's usually the reason many projects fail. Purchase a soldering iron designed for electronics, not for fixing your plumbing! Antex for example make a good inexpensive range.

If you really do get wrapped up in this, later on get a good temperature controlled one, Weller for example.

Believe me, there's nothing worse than spending hours on trying to get something working only to find out it was a duff joint!

Steve A.

http://www.maplin.co.uk/Module.aspx?Mod ... 3&DOY=24m2

http://www.maplin.co.uk/Module.aspx?Tab ... 3&doy=24m2
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Re: Plunging right in - the first step

Postby Viewmaster » Sun Feb 24, 2008 7:45 pm

gary wrote:Unfortunately the club motors do not come with special hubs for the discs. The plastic gears are a push-on fit to the (approx.) 2mm shaft. The discs currently available have a hole in the centre the same size as the motor shaft, so again the gear can be used. People use 'Evostick' glue to fix them to the plastic disc.


To increase the size of this tiny centre hole I turned up a punch with the diameter I required, and with a pilot section same size as small hole.
Then I made a die from brass with hole in it same size as diameter required.
Lined up punch with die on a pillar drill acting as a press, inserted the small hole in the disk onto the pilot and punched down.

NBTV is all about adapting what you have in your workshop (big or small) to what you need to make....."Necessity is the mother of invention." :)
Albert.
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Postby gary » Sun Feb 24, 2008 8:50 pm

I hope by using the word 'unfortunately' that I have not inadvertently given the impression that there is any difficulty in mounting the disks to the motor, because there isn't. The gear wheel method is cheap, easy, and effective.
gary
 

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