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Sparkomatic
Intermediate Member
Username: Sparkomatic

Post Number: 342
Registered: 10-2002
Posted on Wednesday, May 18, 2005 - 2:56 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Keyed up in an 8 pill shootout and the idiot I was keying against stayed on the key long enough after I unkeyed to blow my radio.
I replaced the 1969 final and made no further adjustments. The unit keys and swings OK for the first key and then The radio gets hot very quick and the power drops off. Nothing other than replacing the final was done......I know that messing with the bias can sause a radio to heat up but this radio heats up QUICK.
Any ideas what I am looking at???
I have replaced finals in other 148s and nothing like this has ever happened.
When the radio blew, I smelled something burning but I could not locate an obvious burned component.
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Yankee
Advanced Member
Username: Yankee

Post Number: 559
Registered: 7-2003
Posted on Wednesday, May 18, 2005 - 4:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

sounds like it was just like a radio getting hit by lightning. My Uniden Grant XL was hit by lightning and was brought back to life as good as new by the best technician in the Central Oklahoma area. The Grant was completely dead and had a few printed circuit traces burned. Sounds like a dead short in the 12 volt power circuit on your 148, best bet would be to take it to a good technician and bite the bullet of about a $50.00 service repair charge, a good technician will have all the fancy test equipement to check it out and repair it.
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Sonoma
Intermediate Member
Username: Sonoma

Post Number: 190
Registered: 11-2001
Posted on Wednesday, May 18, 2005 - 6:10 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

check the protector diodes and see if they got hit.that is usually what gets hurt first when hit by power.D1,D2,D22.and D23.I believe they are 1n60's.that is the 1st place I would check and the caps in the chain.
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 783
Registered: 7-2004
Posted on Saturday, May 21, 2005 - 8:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thank goodness my buddy with 2-4cx15000a's only keys up when parked, & not driving around!
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Sparkomatic
Intermediate Member
Username: Sparkomatic

Post Number: 343
Registered: 10-2002
Posted on Monday, May 23, 2005 - 10:30 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I went ahead and left it with a great local tech......for a tech it would be a simple fix, for me a several hour adventure.
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Yankee
Advanced Member
Username: Yankee

Post Number: 577
Registered: 7-2003
Posted on Monday, May 23, 2005 - 2:58 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I would have used a $39.95 ElCheapo AM radio for stuff like that, or does it have to be a sideband rig., in Florida. I've been to a shoot out when I lived in Georgia and they were keying up with cheap AM rigs and real big amps. When I say big I mean big power, like Sweet 16s, and bigger being driven with a 100 watt amp.
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Iluvrf
Member
Username: Iluvrf

Post Number: 92
Registered: 2-2005
Posted on Monday, May 23, 2005 - 7:59 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sweet 16 big??? Thats peanuts to what some of those guys run. Sweet 16s are used for drivers now.....10-15K watts it goes on and on
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 807
Registered: 7-2004
Posted on Monday, May 23, 2005 - 8:43 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

40 & 50kw, supercharged & nitrous injected big blocks, 2nd motor in back of van to run alternators...sick sick sick
i love it!
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Sparkomatic
Intermediate Member
Username: Sparkomatic

Post Number: 345
Registered: 10-2002
Posted on Sunday, May 29, 2005 - 10:09 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Most of us around here use the Cobra 148, 29, 25, and Uniden Grants because of the audio. When you are close someone in signal, you need the audio punch to win.
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Yankee
Advanced Member
Username: Yankee

Post Number: 612
Registered: 7-2003
Posted on Sunday, May 29, 2005 - 2:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Rick, Seems that it would get on the high side of costly to burn up a 148 or Grant for shoot outs.
Most good 148s or the 2 Grants used draw a high dollar and when you burn them up it gets more costly for the repair.
Just my 2 cents.
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Bigbob
Senior Member
Username: Bigbob

Post Number: 1954
Registered: 12-2001
Posted on Sunday, May 29, 2005 - 4:11 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Heck,why don't you guys just skip to the chase and use subdued thermo-nuclear devises,wipe every radio out everywhere with EM pulses,I wonder what effect all that EM radiation is having on your dna.Hey spark can see out the back of your head yet?
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 835
Registered: 7-2004
Posted on Sunday, May 29, 2005 - 10:44 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

yankee-you don't see sparkomatic's problem too often, but keydowns are just like old-time drag races. somebody 'drops the flag' & you both key down. they wave you off & you both unkey. hopefully at the same time. keydowns can have a real 'wild-west' atmosphere should rivals compete. had a guy intentionally remained keyed with MASSIVE wattage, to purposely overload/blowup somebody's radio, you'd probably read about a riot/beating/killing in the paper. seriously. these guys take keydowns EXTREMELY serious. i'd guess in sparkomatic's case his opponent could've been a newbie, a bit overzealous or just not paying attention.

YES, 148/XL's & 25 & 29's have been the KINGS of audio FOREVER. you NEVER EVER EVER see galaxys or magnums or anything else used by SERIOUS competetitors, in any class from 2-pill/DC to unlimited AC/tube.
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Bigbob
Senior Member
Username: Bigbob

Post Number: 1958
Registered: 12-2001
Posted on Monday, May 30, 2005 - 7:03 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

They're to darn expensive to waste on this sport,it's economics,buy 5 148/xls for the price of one dx-99,and who cares about audio in a shoot out anyway,I thought it was MAXIMUM DEAD KEY,hmmm,sounds like a title for a movie.
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Patzerozero
Advanced Member
Username: Patzerozero

Post Number: 845
Registered: 7-2004
Posted on Monday, May 30, 2005 - 8:01 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

the object is to see whose signal can get by anothers. & again it's like professional drag racing, a class may be '8pill X 2 pill driver, DC, single high output alternator, dual optima batteries, any antenna'. no matter what any galaxy fan says, the guys that would be entered in the above class are gonna run 29's or 148's ONLY! maybe 15 seconds of key down time, 1 guy saying 1 word, the other saying another, & it's up to the judges to decide whose signal got over the others. there are ties, resulting in 2nd attempts. resulting, sometimes, in smoke. we have a winner.
i've also seen a custom made fieldstrength meter with MAJOR attentuation record which signal has higher strength at a given distance. 40kw at 100'-who'd like to hold it?

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