| Author |
Message |
    
Freebird
Intermediate Member
Username: Freebird
Post Number: 228
Registered: 1-2003
| | Posted on Monday, June 13, 2005 - 8:02 pm: | 
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hey i have a palamor 450 amp it lights up on high low and med.and the pre amp works but when i key my mic up the amp wont kick on for some reason.any thoughts onwhat it could be? |
Road_warrior
Advanced Member
Username: Road_warrior
Post Number: 657
Registered: 7-2004
| | Posted on Tuesday, June 14, 2005 - 12:20 am: |
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Could be bad relays:
Make sure all your jumper coax and
connectors are good. |
Crackerjack
Advanced Member
Username: Crackerjack
Post Number: 664
Registered: 7-2004
| | Posted on Tuesday, June 14, 2005 - 3:51 am: |
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What type of radio, antenna, coax, and coax length between the radio and the amp? |
Hotwire
Intermediate Member
Username: Hotwire
Post Number: 400
Registered: 1-2005
| | Posted on Tuesday, June 14, 2005 - 10:30 am: |
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I have a good one. When I turn on my preamp I pull in China and other countries on the cb band. I do know these are broadcasts, I can tell that some are commercials. Now if I adjust the voltage going in it sounds like I'm using a VFO and it goes in and out but never really goes away. Anybody?? |
Pig040
Advanced Member
Username: Pig040
Post Number: 802
Registered: 7-2003
| | Posted on Tuesday, June 14, 2005 - 10:34 am: |
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Is this a mobile? If not how are you keying the amp? |
Road_warrior
Advanced Member
Username: Road_warrior
Post Number: 661
Registered: 7-2004
| | Posted on Tuesday, June 14, 2005 - 4:00 pm: |
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Hotwire
You got me on that one...LOL...
Maybe when they built it, they
accidentally dropped there pocket
radio into amp...LOL |
Couchpotatoe
Junior Member
Username: Couchpotatoe
Post Number: 19
Registered: 6-2005
| | Posted on Tuesday, June 14, 2005 - 8:12 pm: |
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FREEBIRD
ITS IN THE PREAMP CIRCUITRY. HAVE SAME PROBLEM ON MY PALOMAR 800V 2X4. OPEN COVERS AND YOU MIGHT SEE SPARK IN THE DARK WHEN YOU KEY THEN UNKEY. TRIED AND FAILED FIXING.
HOTWIRE
IS THAT AMPLIFIER A COBRA XL OR GALAXY MOBILE AMPLIFIER. I'VE GOT A GALAXY 350 (2)2SC2879'S WITH A PREAMP THAT WILL PICK UP ALL TYPE OF FREQUENCIES FROM 500KHZ-12MHZ. THAT TOO I HAVE NO IDEA OF BUT YOU ARE THE 2ND PERSON I HEARD WITH THE VERY PROBLEM.
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Tech291
Moderator
Username: Tech291
Post Number: 199
Registered: 11-2004
| | Posted on Tuesday, June 14, 2005 - 9:08 pm: |
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Freebird,
3 things to check;check clamping diode,D1 for short
check quality of Q1 the switching transistor and also inspect trace side of board for hairline fractures and the solder connections,especially if the amp has been vibrating around in a mobile installation.
Hotwire and others,
There is no preselection designed into the(VERY broadbanded) preamp circuit in these amps,with their high gain and "inexpensive" componants they will tune into a strong signal acting as a reciever itself.one example in the palomar amps,the preamp circuit minus the relay can be built with less than $5.00 worth of off the rack parts from ratshack.
tech291
CEF#291
kc8zpj |
Bc910
Advanced Member
Username: Bc910
Post Number: 534
Registered: 7-2004
| | Posted on Wednesday, June 15, 2005 - 12:34 am: |
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HotWire
I too have had that happen, I always just figured it was harmonics at work...
BC |
Yankee
Advanced Member
Username: Yankee
Post Number: 668
Registered: 7-2003
| | Posted on Wednesday, June 15, 2005 - 12:08 pm: |
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 , BC has hit the nail square on the head. at times preamps no mater what can and will pick up 2nd or 3rd harmonics of an original frequency and most times bring it in on 11 meters around channels 30-33 at times you can listen to Voice Of America or one or two other shortwave stations with a preamp in use.
Carl CEF-357 |
