Resistor value for v1.4 Picasso II board.

[57goldtop]

My board has a burned resistor in exactly the same position as this board found on the Amiga hardware database, you can see the location of it in the photo just below some hand written letters on the right hand side of the board near one of the video ports.

Does anybody who has this version know of that resistor's value ?

Thanks.

[keropi]

damn, I have the v1.2 pII...  :-(
someone will help though!
:bump:

[skurk]

I have a Picasso II+ v1.4 right here.

It's hard to tell what's what, so don't take this for granted.

I think the board print says R307 and the colours are (with the board held equally as on the picture you linked) as follows: Brown, black, black, gold.  No line on the tolerance band.  10 ohms, maybe.. 1% tolerance? I'm honestly not sure - as you can guess, this isn't exactly my field.

But if it helps, on my board, the resistor is identical to these:

[57goldtop]

So they are all the same value in that location ? I'm at work right now so I can't check again.

Is this a common failure on these boards ? I wonder if it's caused by another faulty component. Might try a 1/2 watt resistor instead and see how I go.

[QuarX]

I have one of them, with the same toast aspect and the board working very well  :lol:

Is a 25 Ohm Resistor.

Ciaaa.

[rkauer]

 You can simply swap it for a 1 Watt resistor, so no more heating issues.

[57goldtop]

I have an open circuit there, so i don't know if the monitor will display anything at all, the seller mentioned that his LCD monitor died, I don't know if that is a direct result of the faulty resistor on the card.

Will replace with a bigger resistor.

Cheers.

[rkauer]

BTW: a fast lesson for resistor (and capacitor) values:

 black  = 0
 brown  = 1
 red    = 2
 orange = 3
 yellow = 4
 green  = 5
 blue   = 6
 violet = 7
 gray   = 8
 white  = 9

 silver = divide by 10 (appears only in the 3rd and 4th ring)
 gold   = divide by 1 (means, keep the value)(the same)

 the two first colours are for value, the third is the scientific notation for 10 (ex: in a red, red, yellow, gold 2.2x10e4 = 22000, or 22k, with 5% tolerance), the fourth colour is the tolerance (10% if silver, 5% if gold, direct tolerance if other colour).

 Only 3 colours? Up to 20% tolerance of the printed value.

 Quarx, the resistor have the value altered by repeated heat issues.

[57goldtop]

Quarx, the resistor have the value altered by repeated heat issues.

The value in resistance or the size ?

[QuarX]

I take the value of the resistance with a polimeter.:-D

I´m afraid the value is altered but real value is near 25 Ohm the most common lower standart value is 22.

Red Red Black /gold

Don´t worry about this and fit 22 Ohm 1/2W resistor is not critical.

This resistor is part of monitor switch circuit i think is for drive the relais.

Good luck ;-)

[koaftder]

The lefthand area of the card clearly states BS

[57goldtop]

Replaced the resistor with a 22ohm but the display is not stable. Maybe the value is not correct ??

I get a rolling picture whenever I test any of the Picasso modes in the ScreenMode prefs. I have OS 3.9 installed, Picasso96 drivers, no other drivers installed

Replaced all caps on the card too, tried different monitor displays but it didn't help.

I guess it might be better to get another card.

[rkauer]

 Check all resistors in way of the video out. Maybe one cap died (unstable image is a clear sign of diyng caps).

 Check also mobo caps.

[57goldtop]

Resistors tested fine and I changed every single cap in the card.

The problem could lie within the A3000 power supply. I often see funny little lines on the screen when wb windows pop up, the lines dissappear if windows are moved to overlap the lines or if the screen is refreshed.

I'll test the card in my A4000 to see what happens.

Cheers.

[57goldtop]

After testing the card in my A4000 it worked.I also heard the clicking sound of the relays, never heard that before.

I then reinstalled the card in my A3000 and it worked for the first time. Sounds strange considering that I tried practically everything else to get the card to work, the only explanation seems to be is that the caps near the relays were still charged after the card was powered up in my A4000.

Is there any good online reference material for troubleshooting & repairing an A3000 PSU ?

Cheers.