PSU Issues, Krypts, Eurovoxes Etc

[jambutty]

OK I have decided to post this thread for people who have a box that's dead or stuck on SB.
Some people are asking for my help, BUT it's impossable to give a diagnosis on any psu without testing it propperly.

Switch mode PSU's are a pain. There are so many control loops in them
i.e. everything relying on something else to function, it just needs one
thing to drift out of spec to bring the lot down.

So I am going to give info on these issues on Repairing PSU's.
First of all, Let me put this bluntly, if yer don't know how to read the circuit when testing yerv'e no chance, there are so many control loops you simply won't get very far, yes OK it's nice to have a dabble at trying to save yersel a few quid and it's a great feeling if yer hit on the fault and get it going BUT it's not that simple, let me just say this without trying to sound big headed on this, OK yer don't need to be a rocket scientist to do these basic things.
1 check fuse in Plug:If fuse is ok step 2
2 Yer now need to open the box up to do some more test, after yer open the box have a look for a glass fuse near the power in (be aware that not all psu's will have a glass fuse (I think Eurovoxes Do, BUT Krypts don't) BUT yes a Krypt does have a fuse BUT it's not a glass one, it's again located near the power in looks like a cap but isn't a cap, it's a fuse
I recomend this AND PLEASE BE CAREFUL, This is a basic test to see if power is going to the board, get a Neon Tester and then power up the unit, now touch the Neon to the head of some caps, if Neon lights then we are getting Power and we can now rule out that it is a fuse problem.
3 OK we have now realised that it is not a fuse problem, so this is the point now were you need to know how to test and read components with a Multitester, IF YOU DON'T know how to proceed from this stage then put the lid back on the box and forget trying to repair it yourself becuase if yer not careful you will either do more damage to the unit or in fact to yourself with a potential Electric Shock.
Some people who are a bit more advanced and who can read components with A Multitester CAN try the Caps & Diodes and yer may just locate a shorted Cap Or Diode, BUT if yer do this and then the tested components where reading as OK, whats the next step, as I mentioned above (There are so many control loops) So this is my advice Search internet to see if yer can get a psu for your box, if so then great cos easy eniugh to take the dead one out and replace the new one.
OK yer search internet and can't get a psu for yer box, next step yer will have to take it to a tv engineer, not recomended cos these guys charge a bomb and not all are familiar with them BUT if they are willing to have a look at it then they will more than likely be able to repair the shorted components BUT no guarentee.
I have repaired about 8 KV PSU with no probs as of writting this thread, so if yer still stuck then yer know what to do, but please no time wasters if pming me for advice cos I aint giving any more, all the help you need is in this thread I have composed.
Alan AKA jambutty.
Good Luck and let us know if yer do get a PSU repaired, Not that difficult.

[jambutty]

PSU Issues, Krypts, Eurovoxes Etc

jaysbee666 and a few others have pm ed me on help to repair a psu, any issues on this subject, please see above thread on these issues.

I simply can not give a diagnosis on a dead psu issue without testing it myself.

By the way on the krypt psu's I have noticed that there are 2 different psu's, so when you mention caps 10 11 12 diodes etc, the values may differ depending on which psu is in your kv and I can't advise on this unless I see the psu.

You can do one of 2 things here, if your not fluent at reading components then it's not as easy as you may think to get a psu working.

I hope the admin don't mind me putting this on thead but this is the bottom line.

1 Send me the faulty psu and I will repair it at £15 which includes parts, labour and post cost back to you.

2 £25 and I will send you a brand new psu and you simply replace the knackered one and replace with my new psu.
This is the best way and easiest way But the dearest way cos I will state again, switch mode psu's are a pain in the arse to repair, you either hit the fault or you don't so the choice is yours.
If you want to take my options 1 or 2 then pm me, but please don't pm me for advice on how to repair it yourself cos without seeing the psu there is no way I can give an opinion on the faulty component, it's not ness a cap or diode, it can be other components such as zenner diode, v regulators, blue ceramic caps, dry joint, transformer probs, the faults are endless AND IT'S NOT just caps 10 11 12 or diode 21 that blow kv psu's.
AJ