Help with dead Commodore 1802

[roadrash]

Re: Help with dead Commodore 1802

check your fuses - the lamps should do something even if the cap was not fitted

There is 250v ac entering the psu and the fuse is ok.

[stj]

Re: Help with dead Commodore 1802

check your fuses - the lamps should do something even if the cap was not fitted

[roadrash]

Re: Help with dead Commodore 1802

At last the replacement capacitor arrived.
Ive soldered it in a plugged it in and nothong happened and neither of the light bulbs we soldered in lit up. Should they have? Should i remove that bulb bridging where the resistor was and solder back in the resistor now.

[stj]

Re: Help with dead Commodore 1802

focus can drift as components age - try ajusting it.

[stj]

Re: Help with dead Commodore 1802

try tweeking the focus control - if you know your cables are well shielded

[Agent24]

Re: Help with dead Commodore 1802

WV= Working Voltage. Thats how they some were marked in the past. it just means Voltage rating of the cap.

Some older capacitors may also have two voltage markings; WV for Working Voltage, and SV for Surge Voltage.

[stj]

Re: Help with dead Commodore 1802

you can use 450v if it helps it fit the board better

a rubicon BXW series is probably a good choice if the size matches.

[R_J]

Re: Help with dead Commodore 1802

WV= Working Voltage. Thats how they some were marked in the past. it just means Voltage rating of the cap.

[roadrash]

Re: Help with dead Commodore 1802

Right so I just use a 150uf 400v one then?
What is 400wv or is that just volts?

[R_J]

Re: Help with dead Commodore 1802

That main cap. being open would cause the problem. I had a power smps recently that had a near open main filter and it would blow the main fuse even though everything else (fet etc.) checked ok. All I needed to replace was the main filter and the power supply worked.

[stj]

Re: Help with dead Commodore 1802

yes, it's fuckered as AVE would say!
that could have been the fault.

[roadrash]

Re: Help with dead Commodore 1802

So if that filter cap is 54nf is it ok? Its marked as 150uf and 400wv. Isn't 54nf nano farad?

[stj]

Re: Help with dead Commodore 1802

red purple silver silver is 2.7ohms 10% i think - that's probably less than your test-leads, so it's fine

[roadrash]

Re: Help with dead Commodore 1802

just a thought, check the mains smoothing cap - the big electrolytic.

I temoved it and my component tester says consistanty its around 54nf when it should be 150uf 400wv. I still have this resistor showing a dead short that isba red,purple,silver,silver

[stj]

Re: Help with dead Commodore 1802

just a thought, check the mains smoothing cap - the big electrolytic.

[roadrash]

Re: Help with dead Commodore 1802

I had a few of these nice little oven lights turn up today and ive solderd one in to replace the halogen one so it might be better. I will start removing all semiconductors now one by one (except the caps & diodes that ive checked), until I find whats failed. At least there are not too many.

[stj]

Re: Help with dead Commodore 1802

no idea, i would probably be using a meter on the board.
but testing all transistors is simple - there arent many.

[roadrash]

Re: Help with dead Commodore 1802

I checked and fuses are ok and so far I have checked all the diodes they test with the multimeter as ok. So must be something else like maybe the STR54041 regulator i already replaced earlier or another transistor thats now failed. What do your best guest to go for 1st?

[stj]

Re: Help with dead Commodore 1802

that's good, the faulty part may have burned out.
check the fuse though

[roadrash]

Re: Help with dead Commodore 1802

Just powered it on and the light bulb flashed for anout 8-10 secs and then it stopped and now monitor doesnt turn on any more.