or Connect
AVS › AVS Forum › Display Devices › CRT Projectors › 12XX DIY YPrPb input card...
New Posts  All Forums:Forum Nav:

12XX DIY YPrPb input card...

post #1 of 19
Thread Starter 
Yes folks, it is possible, no transcoding neccesary. At 576P and 480P it looks a lot nicer than SVideo or Composite. Also beats spending silly amounts of money on a line doubler (wish I knew this trick when I had my first 1252!).

I couldn't get hold of a IFB-12 or IFB12A to get progressive scan into my 1252 here in Australia, so I decided to make my own based on instructions for getting an IFB12 to work, and the service manuals.

Its actually very basic. You could run unbuffered video directly from your DVD player, but I preferred to buffer the video with a MAX497 which is one of the few video grade opamps still available in DIP package (for ease of soldering/board design) but it uses a dual rail power supply, so you need to generate a negative supply rail. It is a bit thirsty at 30ma, but doable with a squarewave osciallator + caps + diodes on the 12V rail.

Sync is separated by an LM1881 (a GS4881 would be nicer, and is pin-for-pin compatible, but I had a LOT of trouble sourcing one - it does Tri level sync, but the 1881 only does BI level sync - keep this in mind).

Power is a single +12V rail, which is regulated to +5V for the LM1881 and positive rail of the MAX497, and is switched by the projector as the card is selected (0V is on, +5V is off), which also turns the isolation relays on and off as well.

An odd part of the design is the inclusion of a Medium logic level, which in the projector is generated by a 2.7V zener, but as these are hard to come by, a 3.3V zener fills this role adequately.

If anyone is interested, I can post up the schematic and PCB design, in case you would like to make your own.
post #2 of 19
Quote:
Originally Posted by heathyoung View Post

a GS4881 would be nicer, and is pin-for-pin compatible, but I had a LOT of trouble sourcing one

$2 on ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll...m=220478324085
post #3 of 19
Please post up how you did it and a parts list please. Sounds like a cool project that i would be up for. If you have any images or diagrams please post those too. If not could you at least send me the info so I can see about doing one. Thanks and very cool!
post #4 of 19
PLEASE POST THIS INFORMATION!!!!

I'd love to build a component input for my 1272!

Rudy
post #5 of 19
Thread Starter 
I'm working on a PDF with all of the information etc. that I will post here, and send on to Curt Palme for his CRT website as well if he is interested to enable its furthur distribution.
post #6 of 19
Thread Starter 
Sorry about the delay folks - I had a crash on my bike on the way to work last week and cracked a rib - ouch. But here it is - description, circuit diagram and PCB designs...

Have fun!

 

DIY IFB-12HY Progressive Scan Card.pdf 185.7275390625k . file
post #7 of 19
Dude very cool.
Few questions i have for you or the group here.
1) will this work with a sony 1251q?
2) can anyone put this together in a Eagle format so we can go have have it printed? Or does anyone want to take a run at it and sell the printed boards for DIY people like me?

I'm kinda pumped for putting this together. Other than the PCB board how much did the parts come to for cost? Seems to be it could be done pretty reasonably for cost if you can't find a real card.
post #8 of 19
Thread Starter 
Yeah about that - I actually have a 1251Q (I thought it was a 1252, but it says it on the cover I misplaced in the garage.

Cost - Ummm... I think it ended up around about $45 AUD for all of the parts. I didn't buy it from the cheapest of suppliers, so shopping around should help reduce the cost.

The PCB was hand done with bits I normally have lying around, I used ExpressPCB (badly) to create the pcb, and used press'n'peel and ironed it onto the board. Easy and cheaper than a board house.
post #9 of 19
Sounds great about yours being a 1251Q! Should be cool then for me to use. If you could please post your ExpressPCB file up too that would be great. I would be intrested in making up a few boards at a PCB maker that I use. If anyone would be wanting one I would be up for making a few extra on my run. Thanks!
post #10 of 19
Heathyoung,
Could you post your ExpressPCB file when you have the time? I am looking to go ahead and have some boards made up. Really would help if i could have your file. Thanks!
post #11 of 19
Thread Starter 
I'll post it if I get a chance today, its on my home machine.
post #12 of 19
Thread Starter 
As requested - It still suits a double-single sided (ie. no through-hole plating) approach for anyone who wants to use it.

Zipped BTW. Can't upload.pcb files natively.

To open it, you need the ExpressPcb app from http://www.expresspcb.com/

I don't use their board service, I only use the software to make press-n-peel printouts to make my own.

 

IFB-12HY.zip 31.474609375k . file
post #13 of 19
Quote:
Originally Posted by heathyoung View Post

As requested - It still suits a double-single sided (ie. no through-hole plating) approach for anyone who wants to use it.

Zipped BTW. Can't upload.pcb files natively.

To open it, you need the ExpressPcb app from http://www.expresspcb.com/

I don't use their board service, I only use the software to make press-n-peel printouts to make my own.

Where do you get the press and peel printouts?

Athanasios
post #14 of 19
Thread Starter 
??? Google is your friend...

This... http://www.techniks.com/how_to.htm

Its good stuff, easier than positive photoresist...
post #15 of 19
Say Heath,
Looking to make up a card in a few days and i have a question. What did you use to counter sink the holes on the ground plane and where did you find the internal edge connector to buy? Could you post a finished picture of your finished card? Thanks!
post #16 of 19
Thread Starter 
I countersinked the holes with a 3mm drillbit (by hand).

The edge connector I actually ratted from a blown microphone input card from an Ogenic console (radio station desk), but they are available around the place...

Eg. available from a mob called Altronics here in Australia.

http://www.altronics.com.au/index.as...=item&id=P4896

I'll take some photos tonight if I get a chance for you.
post #17 of 19
Hold on a sec...

I picked up a 1272 a couple of years ago from a fellow forum member that had a home built component input/transcoder on it.

I gave the pj to a friend since I only wanted/needed the spare NEC (...for the lenses!) that he threw in with the deal!

My friend should still have it somewhere in his house!

PM me and I will get in touch with him and ask, I know he still uses the 1272....and if he has it I will send it to you...all you have to do is pay for shipping!

Not sure of how good of a device it is but at least it will take in the signal...I think it was good for 1080i/480P/720p...not sure though!

Worth a shot!

Martin
post #18 of 19
Martin that would be great! Would love to give it a try. I have bought some of the materials for Heath's DIY card but it would be fun to just try my hand at printing off some PCB's.
I'm in Moorhead MN so let me know what you think the shipping would be and i can paypal, check or cash you back. Thanks for offering!
Take care,
Andrew
post #19 of 19
Andrew

You are very welcome, I left my friend an email message a few minutes ago and once he gets back to me it is yours!
I figured no one is using it and it is probably just sitting in a closet or something so why not send it to someone that actually needs it and can make use of it.

Shipping will not be any more than 20 bucks or so.

Will keep you advised

"Morehead" (...what a name!) hehe

Martin
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: CRT Projectors
AVS › AVS Forum › Display Devices › CRT Projectors › 12XX DIY YPrPb input card...