VansAirForceForums  
Home > VansAirForceForums

-POSTING RULES
-Advertise in here!
- Today's Posts | Insert Pics

Keep VAF Going
Donate methods

Point your
camera app here
to donate fast.


Go Back   VAF Forums > Model Specific > RV-4
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 10-28-2014, 03:11 PM
Ofitz Ofitz is offline
 
Join Date: Aug 2013
Location: Merritt Island, Florida
Posts: 26
Default Avionics guru's. Carrier only, no voice.....SOLVED

I tried to take my son flying the other night and while taxiing for fuel, we noticed that the intercom was crackling and he was having trouble hearing me. I tried to ask the tower a question and was getting carrier only, no voice. It was an all the sudden type problem.

After fueling, I unplugged everything and turned off the intercom. When I turned on the avionics master, I could transmit. Once I turned on the intercom though, same thing. Carrier only, no voice.

It has since gotten worse. I can hear everything on the radio, but nothing on the intercom, and I cannot transmit my voice, but I do see the transmit T in the bendix king....

I took out the intercom and played with the wires, checked the breakers, etc. Nothing obvious.

Sigtronics panel mount with Bendix King KX-155 radio.

Any ideas??

Last edited by Ofitz : 10-30-2014 at 12:14 PM.
Reply With Quote
  #2  
Old 10-28-2014, 03:51 PM
Kahuna's Avatar
Kahuna Kahuna is offline
 
Join Date: Dec 2004
Location: Gold Hill, NC25
Posts: 2,419
Default

Sounds like the mic lines to me. Jack, wires to jack, headset jack.
__________________
Kahuna
6A, S8 ,
Gold Hill, NC25
Reply With Quote
  #3  
Old 10-28-2014, 04:31 PM
Ironflight's Avatar
Ironflight Ironflight is offline
VAF Moderator / Line Boy
 
Join Date: Jan 2005
Location: Dayton, NV
Posts: 12,829
Default

I agree with Kahuna - nine times out of ten, a sudden change like that occurs at a connection that has moved - and the most likely candidate is the microphone jack. Plugs get bumped and contacts bent.
__________________
Paul F. Dye
Editor at Large - KITPLANES Magazine
RV-8 - N188PD - "Valkyrie"
RV-6 (By Marriage) - N164MS - "Mikey"
RV-3B - N13PL - "Tsamsiyu"
A&P, EAA Tech Counselor/Flight Advisor
Dayton Valley Airpark (A34)
http://Ironflight.com
Reply With Quote
  #4  
Old 10-28-2014, 04:48 PM
Walt's Avatar
Walt Walt is offline
 
Join Date: Aug 2005
Location: Dallas/Ft Worth, TX
Posts: 6,336
Default

If you could transmit fine with the intercom off then 99% chance its the intercom. With the intercom off its in fail safe mode and voice is routed directly to the radio and not thru the unit.
__________________
Walt Aronow, DFW, TX (52F)

EXP Aircraft Services LLC
Specializing in RV Condition Inspections, Maintenance, Avionics Upgrades
Dynamic Prop Balancing, Pitot-Static Altmeter/Transponder Certification
FAA Certified Repair Station, AP/IA/FCC GROL, EAA Technical Counselor
Authorized Garmin G3X Dealer/Installer
RV7A built 2004, 2000+ hrs, New Titan IO-370, Bendix Mags
Website: ExpAircraft.com, Email: walt@expaircraft.com, Cell: 972-746-5154
Reply With Quote
  #5  
Old 10-28-2014, 06:19 PM
Ofitz Ofitz is offline
 
Join Date: Aug 2013
Location: Merritt Island, Florida
Posts: 26
Default

I tried the front and back headset jacks with the same effect so I don't think it's that...

As it stands now, even with the intercom OFF, I still cannot transmit. I'm going to try again tomorrow.

I'm guessing the intercom is toast also...
Reply With Quote
  #6  
Old 10-28-2014, 07:55 PM
Walt's Avatar
Walt Walt is offline
 
Join Date: Aug 2005
Location: Dallas/Ft Worth, TX
Posts: 6,336
Default

Quote:
Originally Posted by Ofitz View Post
After fueling, I unplugged everything and turned off the intercom. When I turned on the avionics master, I could transmit. Once I turned on the intercom though, same thing. Carrier only, no voice.

Any ideas??
You say it works with intercom off here...

Quote:
Originally Posted by Ofitz View Post
As it stands now, even with the intercom OFF, I still cannot transmit. I'm going to try again tomorrow.

I'm guessing the intercom is toast also...
But now you say it doesn't work here, I give up
__________________
Walt Aronow, DFW, TX (52F)

EXP Aircraft Services LLC
Specializing in RV Condition Inspections, Maintenance, Avionics Upgrades
Dynamic Prop Balancing, Pitot-Static Altmeter/Transponder Certification
FAA Certified Repair Station, AP/IA/FCC GROL, EAA Technical Counselor
Authorized Garmin G3X Dealer/Installer
RV7A built 2004, 2000+ hrs, New Titan IO-370, Bendix Mags
Website: ExpAircraft.com, Email: walt@expaircraft.com, Cell: 972-746-5154
Reply With Quote
  #7  
Old 10-29-2014, 01:24 AM
Doug's Avatar
Doug Doug is offline
 
Join Date: Dec 2005
Location: Sydney, Australia
Posts: 426
Default

If you havn't already, try a different heaset.
__________________
Doug Gray
RV-6 completed, flying since July 2010
Reply With Quote
  #8  
Old 10-29-2014, 08:12 AM
Ofitz Ofitz is offline
 
Join Date: Aug 2013
Location: Merritt Island, Florida
Posts: 26
Default

@Walt: Don't give up yet! :-)

@Doug: I'll try a new headset again to rule that out for certain.

I'm going to look at it again today. The problem is sort of intermittent in that sometimes I can make the radio work again, but yesterday I ran out of time. When I left, I could not transmit. It doesn't seem to follow a pattern that I can discern.

I may need an avionics guy to look at it. I'll let everyone know the outcome.
Reply With Quote
  #9  
Old 10-29-2014, 02:54 PM
SteinAir SteinAir is offline
 
Join Date: Feb 2005
Location: Minneapolis
Posts: 2,478
Default

At the moment with what we know based on your report, Walt is likely spot on here (that being if it works with the avionics switch off). Most intercoms are made to fail over directly to the radio when power is removed...therefore if you shut it off, your jacks effectively are wired directly to the radio - which typically explains why they will work when the intercom is off, but not when it's on.

If it were a jack wiring it would either work all the time or not work all the time...that's the nice thing about that.

You definitely need to figure out whether it IS or is NOT working without power and with power before worrying about any other troubleshooting. Once that step has been completed, then you can look at headsets, jack wiring, etc..

Cheers,
Stein
Reply With Quote
  #10  
Old 10-30-2014, 09:25 AM
Jerry Fischer's Avatar
Jerry Fischer Jerry Fischer is offline
 
Join Date: May 2007
Location: Winder Ga
Posts: 934
Default I had a similar problem...

Just some input from personal experience. When I was wiring up the Mockingbird last year in Creswell Oregon for the x-country flight back to Winder, I had a transmit problem. Only after switching headsets with help from Gary Ludeke, did I find my electret element in the David Clarks had gone south from shipping out to west coast. After a quick trip to Pacific Coast Avionics for a new mike element, problem solved. Hope this helps.
__________________
Jerry Fischer KW4F
VAF# 1646
USS Randolph CVS-15 V-6 Div. AT2
RV7 N364SJ Miss Sandy sold
RV1 N1583 "Mockingbird 1" SOLD
EAA volunteer SNF

HBC volunteer/co-chairman OSH
Tech counselor
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 02:37 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.