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Rich Brazell
PostPosted: Fri Jun 13, 2014 4:51 pm 
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This problem came out of the blue . I was in the driveway running the engine to warm it up for an oil change and was listening SOCAL Approach...nothing better to do . Radio working fine and squelch could be turned up and down no problem . My Microair has a green lite that comes on when the squelch is turned up . Shut down , changed oil and tugged the AC back into the workshop . I had been having trouble with the fuel gauge bouncing around and knew it was just a loose connection . Tilted the panel found the loose connection . As I always do I power up the panel and check that everything is working . This time my green squelch lite is on and I can not turn it off with the squelch knob ? I know what you are thinking...another loose connection . I went thru everything and found nothing . If I remove the coax antenna connection from the back of the radio the lite goes out . OK...maybe the radio ? I have a spare radio and put that in only to find the same problem with the squelch . Bad coax connector ? Replaced it . Same result . Have a spare antenna and premade coax and attached it to the radio . Works 4.0 ?

Now I start to work down to the AC antenna . I disconnect the coax from the AC antenna and attach it to the spare antenna . Works 4.0 ? Must be a bad ground on the AC antenna . Removed the AC antenna cleaned all the attach screws , mounting holes and the skin inside the AC and the doubler mounting plate . Put it all back together and can not get the squelch lite to go out ? If Mr. Wizard is out there tell me what I am missing !

RB O0


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lance38dt
PostPosted: Fri Jun 13, 2014 6:44 pm 
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Measure with a Dvm from center connector to ant. Base then check the one that works ant could be partially shorted ohms scale.

Lance


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Rich Brazell
PostPosted: Fri Jun 13, 2014 6:55 pm 
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I'll try that , but it seems strange that when I disconnect the original coax installed in the AC at the ant. and hook up the spare ant. (ant not installed in AC , but grounded) the Squelch works . It even worked when I removed the RAMI AV-17 ant. from the AC and hooked it up to the current coax ? >:(

What reading should I see on the Ohm meter ? ???

RB O0


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lance38dt
PostPosted: Fri Jun 13, 2014 7:03 pm 
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Depends if it is a loaded ant. But you did all the right things and sounds like you isolated the problem you will probably get a very low reading, compair the readings between both antennas. Look real close at the base of the ant and see if you can see any foreign substance.

Lance


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Fraser MacPhee
PostPosted: Fri Jun 13, 2014 7:05 pm 
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Friday the 13th and a full moon.....

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Rich Brazell
PostPosted: Fri Jun 13, 2014 7:31 pm 
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Thanks Lance . I'll do the readings in the morning . I'll been in and out of that cockpit at least 10 times today and the same for the last 3 days . When I removed the AC antenna , I cleaned everything . The only thing I did not do is remove the rubber gasket that goes between the ant. base and the bottom of the AC . The installation instructions state the ant. gets it's ground from the 4 screws that attach the ant. to the doubler plate inside the AC . If the ant. attach points were any cleaner they would have to testify before Congress and plead the Fifth !

Full Moon ? The only full Moon I see is your Arse hanging over your patio balcony after a few Barley Pops ! :o

RB O0


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fytrplt
PostPosted: Fri Jun 13, 2014 7:53 pm 
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I suppose you towed the plane out of the garage/hangar and checked it. Could be interference from some source in the house (air conditioner?). Even fluorescent lights can mess you up.

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Rich Brazell
PostPosted: Fri Jun 13, 2014 10:03 pm 
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Bob: At this point I'll try anything . The panel was built and tested in the shop and the radio has work flawlessly for over 3 years . I'll tow it out into the driveway and give it a try . The spare radio does the same thing . It's also about time to do a wire wiggle test also . It has to be something simple that I am over looking ? ???

RB O0


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Rich Brazell
PostPosted: Sat Jun 14, 2014 11:24 am 
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Bob...you the man! I had never had a problem with using/testing the radio in the shop/hangar until now . I towed the AC back on the driveway , powered up the radio and the problem went away ! BOOM ! One possibility is that I just remodeled the hangar putting down a new epoxy on the floor , installing several new metal cabinets and moved around and repositioned the big iron machinery . I owe you the beverage of your choice along with lunch . Thanks Bob . You saved me many more hours of trouble shooting . :)

RB O0


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Ryan Allen
PostPosted: Sat Jun 14, 2014 12:29 pm 
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dang! now that is something....never in a million years would I have figured that one out.


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Rich Brazell
PostPosted: Sat Jun 14, 2014 1:45 pm 
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Sooner or later I would have gone back to square one where the radio did work ...in the driveway . Bob put the idea in my head a lot sooner ! I think it was the addition of the metal cabinets and repositioning the shear , brake and 3 large metal tool boxes . ???

RB O0


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dan
PostPosted: Sat Jun 14, 2014 9:38 pm 
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I think that the tool cabinet , and the 3 tool boxes you had rearranged on top of the radio could have been the culprit, just can't figger out how you got em under you panel?? Dan


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Rich Brazell
PostPosted: Sun Jun 15, 2014 4:24 pm 
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Very carefully ! ??? Plan to arrive at U-42 around 1230 (L) ? Fuel stop at St. George . ;)

RB O0


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Rich Brazell
PostPosted: Sun Jun 15, 2014 5:06 pm 
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Never take anything for granted . I pulled the AC back onto the driveway and I had Sil with the handheld drive up and down the street for a radio check . OPS normal . I then tugged the AC back into the shop but is a slightly different spot...you guessed it the squelch worked ! :o This ends my squelch thread . ??? BOOM !

RB O0


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Fraser MacPhee
PostPosted: Sun Jun 15, 2014 7:03 pm 
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I still think it was Friday the 13th and a full moon that caused it....

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