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Drfeelgood
Posted on Thursday, March 06, 2003 - 10:58 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hello
i have a palomar 300a when you key it up it will throw the braker in the house i have pulled all the tubes out of it an with no tubes in it still does the same thing nothing looks burnt in it everything looks good but i cant seem to figure this one out any help?
thanks.
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2600
Posted on Friday, March 07, 2003 - 12:15 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Uhh, you didn't take the transformer from ONE amplifier and match it up with a DIFFERENT amplifier box, did you? The 300A was made with two different transformers, which look identical on the outside. If you MIS-match the wrong transformer type (plugs are the same on both), it will fry the high-voltage filters and rectifiers. They MIGHT or might not LOOK damaged and still be dead-shorted inside. Try unplugging the transformer before applying power. If it ONLY blows the fuse with the transformer PLUGGED IN, it's time for someone familiar with high-voltage safety standards to dig deeper. Any amp that blows fuses like this should be tested gently with a "Variac" or equivalent tool. It permits turning up the AC juice feeding it SLOWLY. If you have fixed the short, no problem. If there is still a short-circuit inside the equipment, you don't get the big, scary current surge that keeps blowing your house breaker. Much safer for the equipment, and your house.
If you must 'test' it use a 5-Amp fuse. It isn't big enough for 'High' side, but will hold just fine on standby and on 'Low'. This will minimize the chance of frying your transformer. It may be blown already. Or, it may be the WRONG TYPE, unless you are SURE those two pieces USED TO work okay together.

73
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Crafter
Posted on Friday, March 07, 2003 - 1:37 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sounds like a cap to me. But usually they only do it on key up.
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Drfeelgood
Posted on Friday, March 07, 2003 - 2:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hello
thanks guys for the help here about the transformer 2600 i'm not for sure if it is the right one or not. see i got 3 of these things off a buddy of mine an 2 of them were junk out but all 3 transformers look alike just as you said but the boxes were different 2 of them have the stand up boards in them with the small relays on them do you know the kind i'm talking about? they are the ones junk out. the other one does not have the stand up board with the relays on it. its made just a little different on the in side compaired to the other too,but other than the stand up board that plugs in the other to it looks the same. it does not blow the fuse in the box when you turn it on with or without the transformer on the unit with it in standby you can key it an it works like it should letting the watts go through it from the radio but when you flip it on to operate an key it down it will dim the lights down in the house an if you hold it for a sec it will throw the breaker. how can i tell which transformer is the one for it or can you by just looking? i'll try all of them this evening to see if i can find the right one for it an i will also change the caps in it crafter. are you talking about the ones in the bottom of the box? the 2 large blue ones? get back to me on this if you can an once again thanks for your help you all are a great bunch of guys.
thanks.
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Crafter
Posted on Friday, March 07, 2003 - 7:53 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yes the 450 volt one's.
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Drfeelgood
Posted on Saturday, March 08, 2003 - 9:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hello crafter an 2600
well i got the old palomar up an going works like a top it had the caps in backward an it was the wrong power supply took me a little while to test an get it all straighten out but with your guys help i did it an i thanks the both of you very much if there was more people in the world like you fellows it would be a much better place to live. thanks guys an if i can help you all in any way i'll do my best to help.
thanks again.
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2600
Posted on Sunday, March 09, 2003 - 2:31 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Congratulations. It took patience to sort out that one. Glad we could help.

73
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Tecnicoloco
Posted on Monday, June 09, 2003 - 6:38 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hello Drfeeelgood:
I wonder if you still have any of the spare power supply's for the 300a,I been looking for one,please let me know if you consider sell me one.

Thanks in advance.
Tecnicoloco

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