a500 Video hybrid mod

[kipper2k]

Hi all,

Just thought i'd show you the video hybrid mod i done for the a500.. I built it as people who are going to build the GB1000 boards may need it. (its the small board sticking up behind the Denise chip). I removed the original so i could test it. The original was version 01 and the one i replaced it with was version 3. I also done a complete recap of all electrolytic caps on the motherboard, One thing i noticed was the slight blinking of the screen everytime the floppy was being accessed was cured

[amiman99]

Nicely done kipper, as always!
How about color version? A drop in replacement for A500/A2000? Can it be done?

[kipper2k]

Originally Posted by amiman99

Nicely done kipper, as always!
How about color version? A drop in replacement for A500/A2000? Can it be done?

once you remove the old one, you can use a 22 pin single in line female header soldered to the motherboard and then just "plug" this board in

[Yakumo9275]

nice going! are you going to get these made in bulk or sell as a pcb + parts kit?

[kipper2k]

Originally Posted by Yakumo9275

nice going! are you going to get these made in bulk or sell as a pcb + parts kit?

I'll sell complete ($11) or parts ($5) its a pain to build, 40 tiny resistors/caps and 6 transistors

[hooverphonique]

and what does this do compared to the original vidiot?

[kipper2k]

Originally Posted by hooverphonique

and what does this do compared to the original vidiot?

The Vidiot is a hybrid integrated circuit that works as digital-to-analog converter for the OCS/ECS generation's 12 bit video to analogueRGB output. It also generates a monochrome composite video signal and combined sync. The A3000 uses one Vidiot each for 15 kHz video and for 31 kHz (Amber) output. AGA Amigas use off-the-shelf DACs.

I've never seen the vidiot so i cannot say. but for the A500's and GB1000 this is what is used to generate the RGB signals

[dJOS]

Ok, maybe im dense but what does yours do that the stock unit doesnt?

[kipper2k]

I think people are missing the point, i made it because the video hybrid chip is hard to find (and probably expensive) The GB1000 boards need 2 of these hybrid boards for full functionality so it will be hard to find these things without destroying A500's to salvage the Video hybrid chip.

Commodore made 3 versions of this hybrid chip and the last version (03) is assumed to behave better than version 01. I didnt make it to replace your original video hybrid chip on the A500, there is no need. I removed mine so i could test the one i built, nothing more than that

[dJOS]

Ah that makes sense now.

[pandy71]

Kipper perhaps it will be some market for Vidiot with color encoder like AD724 that can be used to upgrade A500/A2000.

[jimbob]

Are these available for non GB1000 customers at the moment? I think I might need one for this . . .

[Loedown]

Originally Posted by kipper2k

I'll sell complete ($11) or parts ($5) its a pain to build, 40 tiny resistors/caps and 6 transistors

If you do one run of say 1000 of these and sell them for the prices above won't you make your money back on a single SMT house built run of parts with such a simple design and simple parts? Even the old Yamaha YV series SMT pick and place machines could do them no sweat and it's no more than about 3 hours work maximum, 50 boards per carrier or even 100, design is simple it just comes down to the offsets, wouldn't even need fiducials because the parts are 1206 / 805 / SOT23.

[kipper2k]

Originally Posted by Loedown

If you do one run of say 1000 of these and sell them for the prices above won't you make your money back on a single SMT house built run of parts with such a simple design and simple parts? Even the old Yamaha YV series SMT pick and place machines could do them no sweat and it's no more than about 3 hours work maximum, 50 boards per carrier or even 100, design is simple it just comes down to the offsets, wouldn't even need fiducials because the parts are 1206 / 805 / SOT23.

The first batch i made 25, (the board house supplied me with 5 free ones I tested to make sure it worked, which it did. I then modified it to give it less height and then ordered 80. So far, with the build of the GB 1000 board i have actually sold 50 complete and 20 as kits. Once the rush has died down for the GB1000 then i don't think there would be much of a market for them.

I could easily modify them to include colour composite output with built in onboard Svideo but i don't know what the demand would be like as ultimately if people wanted to use them for their A500 and other projects then there would be the desoldering of the old component which some people shy away from. (I could even include the Chipquik to help them

[GadgetUK]

Awesome, I wouldn't mind buying a couple of these. Does it give cleaner output or is it just a replacement? Did the original fail?

Originally Posted by jimbob

Are these available for non GB1000 customers at the moment? I think I might need one for this . . .

Omg, what happened there?

[kipper2k]

Originally Posted by GadgetUK

Awesome, I wouldn't mind buying a couple of these. Does it give cleaner output or is it just a replacement? Did the original fail?

The output is really clean. Like i said, i built these as the GB1000 boards require 2 of these and the only other way to get these would be to remove them from 2 Amigas which is sacriligous.

Anyone can buy, if you need one, just let me know. I'll throw in a bit of Chipquik to make removal a lot easier for $1

[jimbob]

Originally Posted by GadgetUK

Omg, what happened there?

I bought a faulty 500+ motherboard. With a bit of luck this is all that is wrong with it.

@kipper - Order incoming, if I buy a kit is there a BOM/schematic/layout to follow.

[Loedown]

Originally Posted by kipper2k

The first batch i made 25, (the board house supplied me with 5 free ones I tested to make sure it worked, which it did. I then modified it to give it less height and then ordered 80. So far, with the build of the GB 1000 board i have actually sold 50 complete and 20 as kits. Once the rush has died down for the GB1000 then i don't think there would be much of a market for them.

I could easily modify them to include colour composite output with built in onboard Svideo but i don't know what the demand would be like as ultimately if people wanted to use them for their A500 and other projects then there would be the desoldering of the old component which some people shy away from. (I could even include the Chipquik to help them

As it's a SIL connection it's very easy to remove because as you desolder it you can wobble the part to see which pins are still attached. I got a specialized tool made many years ago which is about the thickness of a pencil and has a hole drilled into the end of it to wiggle the pins after you desolder them.

[kipper2k]

Originally Posted by jimbob

I bought a faulty 500+ motherboard. With a bit of luck this is all that is wrong with it.

@kipper - Order incoming, if I buy a kit is there a BOM/schematic/layout to follow.

.

Hi,

I will post the layout for you. One thing to remember (and i am not trying to get an extra $6 from you). The complete ones are proven and tested working. If you buy a kit and dont build it properly and it doesnt work you may think you have other issues with the motherboard.

@Loedown,

I use desoldering braid and lots of flux to remove most of the solder and then a little bit of chipquik and light heat will finish it off. Just need to resist the urge to pull too hard and rip the pad off the board.


here's the links to the placement

http://www.kipper2k.com/amiga/videoh...dhybridtop.pdf

http://www.kipper2k.com/amiga/videoh...dhybridbot.pdf

Here's the BOM



Part Value Device Package Description

C1 0.1u C-USC0805 C0805 CAPACITOR,

C2 0.1u C-USC0805 C0805 CAPACITOR,

C3 0.1u C-USC0805 C0805 CAPACITOR,

C4 0.1u C-USC0805 C0805 CAPACITOR,

C5 0.1u C-USC0805 C0805 CAPACITOR,

Q1 MMBT3904LT1-NPN-SOT23-BEC SOT23-BEC NPN Transistror

Q2 MMBT3904LT1-NPN-SOT23-BEC SOT23-BEC NPN Transistror

Q3 MMBT3904LT1-NPN-SOT23-BEC SOT23-BEC NPN Transistror

Q4 MMBT3904LT1-NPN-SOT23-BEC SOT23-BEC NPN Transistror

Q5 MMBT3904LT1-NPN-SOT23-BEC SOT23-BEC NPN Transistror

Q6 3906LT1SMD MMBT3906LT1SMD SOT23-BEC PNP Transistror

R1 1k R-US_M0805 M0805 RESISTOR,

R2 2k R-US_M0805 M0805 RESISTOR,

R3 4.02k R-US_M0805 M0805 RESISTOR,

R4 8.02k R-US_M0805 M0805 RESISTOR,

R5 470 R-US_M0805 M0805 RESISTOR,

R6 390 R-US_M0805 M0805 RESISTOR,

R7 75 R-US_M0805 M0805 RESISTOR,

R8 75 R-US_M0805 M0805 RESISTOR,

R9 1k R-US_M0805 M0805 RESISTOR,

R10 2k R-US_M0805 M0805 RESISTOR,

R11 4.02k R-US_M0805 M0805 RESISTOR,

R12 8.02k R-US_M0805 M0805 RESISTOR,

R13 470 R-US_M0805 M0805 RESISTOR,

R14 390 R-US_M0805 M0805 RESISTOR,

R15 75 R-US_M0805 M0805 RESISTOR,

R16 75 R-US_M0805 M0805 RESISTOR,

R17 1k R-US_M0805 M0805 RESISTOR,

R18 2k R-US_M0805 M0805 RESISTOR,

R19 4.02k R-US_M0805 M0805 RESISTOR,

R20 8.02k R-US_M0805 M0805 RESISTOR,

R21 470 R-US_M0805 M0805 RESISTOR,

R22 390 R-US_M0805 M0805 RESISTOR,

R23 75 R-US_M0805 M0805 RESISTOR,

R24 75 R-US_M0805 M0805 RESISTOR,

R25 1k R-US_M0805 M0805 RESISTOR,

R26 220 R-US_M0805 M0805 RESISTOR,

R27 27k R-US_M0805 M0805 RESISTOR,

R28 150 R-US_M0805 M0805 RESISTOR,

R29 75 R-US_M0805 M0805 RESISTOR,

R30 90.9k R-US_M0805 M0805 RESISTOR,

R31 37.4k R-US_M0805 M0805 RESISTOR,

R32 13.3k R-US_M0805 M0805 RESISTOR,

R33 6.04k R-US_M0805 M0805 RESISTOR,

R34 37.4k R-US_M0805 M0805 RESISTOR,

R35 19.6 R-US_M0805 M0805 RESISTOR,

R36 270 R-US_M0805 M0805 RESISTOR,

R37 36 R-US_M0805 M0805 RESISTOR,

R38 36 R-US_M0805 M0805 RESISTOR,

R39 75 R-US_M0805 M0805 RESISTOR,



All resistors are of the thick film type and 1% tolerance.

[Shadowfire]

Originally Posted by Loedown

As it's a SIL connection it's very easy to remove because as you desolder it you can wobble the part to see which pins are still attached. I got a specialized tool made many years ago which is about the thickness of a pencil and has a hole drilled into the end of it to wiggle the pins after you desolder them.

I have one of those too. They're called tweezers.