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Al_lafon
Junior Member
Username: Al_lafon

Post Number: 20
Registered: 3-2005
Posted on Sunday, May 22, 2005 - 10:38 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hello have a superstar 3900 gold plus
the radio has a squeal am tx rhis is with
a stock or power mic in line don't see this in ssb ? can someone put some light on this so it
can be fixed !
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Snowfire
Member
Username: Snowfire

Post Number: 85
Registered: 2-2004
Posted on Sunday, May 22, 2005 - 11:26 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Turn mic gain down. Hope this help's
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Bruce
Senior Member
Username: Bruce

Post Number: 2652
Registered: 9-2003
Posted on Sunday, May 22, 2005 - 11:42 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Bad design ........Ok you can try puting a small value cap ( .001UF ) between mike hot and ground or a ferite bead on the mike hot lead. Now if your antenna is bad this might cause this too.
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Vanillagorilla
Junior Member
Username: Vanillagorilla

Post Number: 44
Registered: 4-2005


Posted on Sunday, May 22, 2005 - 1:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)


This is in a mobile or base? If in a mobile try a shorter ground to chassis...9" comes to mind. If you still have the squeal then ground the rear radio chassis to the vehicle chassis as well. The good posters here on this forum taught me that :-)
Worked like a charm for me.
Unless the radio has been clipped and mod limiter disabled I see no reason why you should squeal with the stock mic. A power mic turned to "10" and mic gain at "Full" could easily overdrive into a squeal.
Also....got talkback? Turn it off and get a radio check to confirm thats not the problem (feedback)
If you have TB and can use an external speaker then move it AWAY from you and the radio...far away. :-)


Good luck,
Hank '905
CEF 559
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Al_lafon
Junior Member
Username: Al_lafon

Post Number: 21
Registered: 3-2005
Posted on Sunday, May 22, 2005 - 8:27 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Well thanks so far i will take a good look inside
to see if the guy at the shop i got it from cliped mod limiter i do know he had cut a diode
to give talk back i have undid that work. Never
had to ground a radio but give it a try :-)
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Big_l
Junior Member
Username: Big_l

Post Number: 39
Registered: 6-2004
Posted on Sunday, May 22, 2005 - 8:45 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

ALWAYS check connections for squeal issues!
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Al_lafon
Junior Member
Username: Al_lafon

Post Number: 22
Registered: 3-2005
Posted on Monday, May 23, 2005 - 6:18 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hay was looking around about this aqueal found this.( DX 2517 and DX 2527 ) SYMPTOM:
Buzzing or motorboating sound in either the transmit or receive
PROBLEM:
TR602 is oscillating
SOLUTION:
Replace C602 with a .01uF cap
Remove C608
but the part call out is not for my radio ??
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Hotwire
Intermediate Member
Username: Hotwire

Post Number: 367
Registered: 1-2005


Posted on Monday, May 23, 2005 - 7:45 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yeah, lose or dirty conectors or high swr. Check your antenna.
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Al_lafon
Junior Member
Username: Al_lafon

Post Number: 23
Registered: 3-2005
Posted on Monday, May 23, 2005 - 5:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ok guys this is what ifound Truck Stop Tech
likes to mod all his radios before he puts them out .
Found D75 cliped This gave me real bad Talkback Squeal ( fixed ) that right off.
Next i find Q39 has been cut right out leaving legs in think this is mod control going to put that back.
Next we find one end of R26 now has a diode on it unknown mod as yet will put that back the way
it was. The SWR is good in low.
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Dale
Member
Username: Dale

Post Number: 80
Registered: 12-2002
Posted on Monday, May 23, 2005 - 6:47 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

sounds like a chop shop. thats what shops do when they dont know how 2 correctly tune them
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Bruce
Senior Member
Username: Bruce

Post Number: 2670
Registered: 9-2003
Posted on Monday, May 23, 2005 - 7:20 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

And the FCC did away with the old 2nd class.....

At least there was SOME accountably
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Al_lafon
Junior Member
Username: Al_lafon

Post Number: 27
Registered: 3-2005
Posted on Wednesday, May 25, 2005 - 7:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Been Telling the Drivers in my area about what i
found in my radio and told them who had done this
also posted some notes at the truckstop.
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Hotwire
Intermediate Member
Username: Hotwire

Post Number: 383
Registered: 1-2005


Posted on Thursday, May 26, 2005 - 11:03 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

When you find a good tech ya better keep him close and always tip him. Hey I bought my tech lunch while he was performing his magic on my 148. A 2 hour job to make my Cobra one of a kind.Well at least one in a million. If you can find a tech that dont lie then you got a good one because if he dont know how he wont try and say he can. Easy to spot a chop shop if you have radio expierience and know a little here and there. It ok to advertise on 19 if your a truck stop shop but the best dont advertise. They make it by word of mouth and by the work they have on the road and DX land.

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