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Rollingrock
New member
Username: Rollingrock

Post Number: 2
Registered: 3-2004
Posted on Tuesday, March 09, 2004 - 3:12 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

This was awhile ago but I just wondered if anyone has any ideas. I used to run a Uniden PC 76XL with a TX Star DX 250HDV behind it. Antenna was a 102" steel whip on a bumper mount grounded to the chassis of my 1994 Ford Ranger. SWR was 1.1-1.2 all the way around. The radio was set to a 2 watt deadkey with a full 4 watt forward swing. Now heres the question. I decided back then (didn't know much about radio) that I needed more, so I bought a Cobra power mic. I don't remember the model but it had a 9 volt batt. with a dial that read 1-10 on the front. I have a bad habit of letting the mic just barely touch my top lip when I key. The funny part? the first time I keyed the mic I had the amp on and the mic set to about 5 on the dial and I about jumped through the roof of my truck!. The mic, where it was touching my lip,shocked the heck outta me. Any ideas on what would cause this? It wouldn't shock me with the amp off.
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Buck
Advanced Member
Username: Buck

Post Number: 815
Registered: 3-2002
Posted on Tuesday, March 09, 2004 - 7:53 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Sounds like stray RF.....Ground the amp good. One good thing about it.....It will keep you awake when you are driving:-)
Buck
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Bigbob
Senior Member
Username: Bigbob

Post Number: 1720
Registered: 12-2001
Posted on Tuesday, March 09, 2004 - 10:45 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

yeah ground the amp and put a 47 ufd cap rated at least at 16 volts across the power leads of the amp,and find out what wire is in contact with the mike housing and put a 1/100th ufd disc cap across it and ground in the radio chassis,this should cure it.A bumper mount is ok with 4 watts but when you start loading up with POWER remember it's going in your cab too,getting on the outside of your radio and amp,I've actually heard of guys running 20K and getting little lightning bolts jumping from vehicle chassis to the actual ground,NOW THAT'S STRAY RF,WOW!Bigbob
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Crafter
Advanced Member
Username: Crafter

Post Number: 968
Registered: 12-2002
Posted on Wednesday, March 10, 2004 - 12:02 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

LOL, had a turner 76 the noise canceling power mic with a rubber bumper that I did the same thing with my 667. It was the GROUNDING since I had NONE. Was in my early days as a new fish in a big pond.
Learned later not to hold my meter with 3k going through it too you know that imprint on the dosy case It was in my fingers for weeks. Also gave me RF burns, anyone that has ever had then knows what Im saying when I say thats a different feeling!
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Crafter
Advanced Member
Username: Crafter

Post Number: 969
Registered: 12-2002
Posted on Wednesday, March 10, 2004 - 12:06 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Same year I was in the hospital because I got tangled to a LITTLE amp called a HAWK. Nearly killed me so the doctor said had to stay in the hosp two days over that. Needless to say I am more careful now with anything over 350 volts. I now always keep someone near me when working on big stuff to kick me off it just in case.
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Bigbob
Senior Member
Username: Bigbob

Post Number: 1722
Registered: 12-2001
Posted on Wednesday, March 10, 2004 - 6:08 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Crafter you are darnlucky to be alive.
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Crafter
Advanced Member
Username: Crafter

Post Number: 972
Registered: 12-2002
Posted on Thursday, March 11, 2004 - 1:50 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I truely have the deepest respect for DC voltage now. I have been known to grab a 450 volt cap and the owner if I catch them operating with the cover off of it though. NOW MY WARNING: dont attempt this at home it can kill ya.

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