| Author |
Message |
    
Cornbred
Junior Member
Username: Cornbred
Post Number: 12
Registered: 2-2004
| | Posted on Wednesday, October 26, 2005 - 8:21 am: | 
|
I have a 25 amp radio shack switching power supply with cooling fan,it comes on but doesn't produce any power to fan or radio. |
Tech808
Moderator
Username: Tech808
Post Number: 7787
Registered: 8-2002
| | Posted on Wednesday, October 26, 2005 - 8:30 am: |
|
Cornbred,
#1 ~ Unplug the Power Supply
#2 ~ Get a pair Rubber Gloves and put them on.
#3 ~ Remove the cover and check to see if you have blown a fuse or have shorted / burnt / damaged traces or parts inside of the power supply when you remove the cover.
Hope this helps,
Lon
Tech808
CEF808
N9OSN |
Cornbred
Junior Member
Username: Cornbred
Post Number: 13
Registered: 2-2004
| | Posted on Wednesday, October 26, 2005 - 8:39 am: |
|
Tech808 the fuse is good and no burnt/damaged traces. |
Tech808
Moderator
Username: Tech808
Post Number: 7789
Registered: 8-2002
| | Posted on Wednesday, October 26, 2005 - 8:45 am: |
|
Cornbred,
Then if you have power going into the transformer and NO Damage to any other parts and all parts are working except the transformer and no power coming out of transformer you need a new transformer.
Depending on how old it is you may find it cheaper to just get a new power supply
Lon
Tech808
CEF808
N9OSN |
Cornbred
Junior Member
Username: Cornbred
Post Number: 14
Registered: 2-2004
| | Posted on Wednesday, October 26, 2005 - 8:54 am: |
|
Tech808 it's about 2 years old,might have to buy another one,or would it be cheaper to get a transformer,being it's only 2 years old |
Tech808
Moderator
Username: Tech808
Post Number: 7797
Registered: 8-2002
| | Posted on Wednesday, October 26, 2005 - 5:46 pm: |
|
Cornbred,
Check with your Local Radio Shack and see what a new Transformer would run you for one if they still stock replacement parts for the model you have.
Then you will have to decide if it is worth it to fix it or get a new one.
Good Luck,
Lon
Tech808
CEF808
N9OSN
|
Therealporkchop
Intermediate Member
Username: Therealporkchop
Post Number: 429
Registered: 11-2002
| | Posted on Thursday, October 27, 2005 - 12:40 am: |
|
If it's got power coming out of the transformer, then you'll probably need to replace the bridge rectifier in it, assuming it has one. I'm pretty sure all power supplies have them to rectify current. |
Tech291
Moderator
Username: Tech291
Post Number: 273
Registered: 11-2004
| | Posted on Thursday, October 27, 2005 - 9:40 pm: |
|
Cornbred,
Switching type power supplies are a little more complex than linear type supplies.They raise the voltage,change the frequency so they can be easier to regulate,then rectified to dc and then lowered to the user voltage.Get out the magnifier and bright light and look over the trace side of the board looking for a possible broken solder joint or crack around component leads.make sure the ballest resistors on the sense voltage have not gone bad.the line above where I said they raise the voltage,we're talking in the 400 to 650 volt range so be careful.If the supply has ever been dropped,possibly the torid core has cracked and the only fix for that is replacement.Your best bet is to take back to RS and have them send it to their repair facility.
tech291
cef#291
kc8zpj
|
