No body will answer me!!!

bahama flier

Pre-takeoff checklist
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Jan 15, 2014
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Deland, Florida
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bahama flier
Left for the Bahamas tried to open flight plan, no answer... had to get Orlando class B clearance, called and called no answer.... then I checked my radio for the transmit light... it was not coming on,,, crap, crap, crap, or something like that.

U turn back to my airport, I could hear but not transmit, no tower at my airport, so I watched the pattern and jumped in and did a quick landing and got off the runway.

I have a portable radio, but it was under stuff in the back of the airplane, (Cherokee six) seats out, lot of stuff. I know the portable should be in easy reach,, duh, in 900 hours never used it,, did not think about it. Never used my ELT either, my life jackets, or my inflatable raft, but they are in easy reach,,, why did I bury my portable radio, I don't know,,,

My Bahamas trip was cancelled, my audio panel in the shop, my portable radio would not have made me to continue on to Bahamas, but I would have made a safer return to my airport. My portable radio usually is clipped to the side panel by me during flight, but now its also on my check list.
 
Stop trying to transmit on the radio until you have checked the SWR. If the SWR is high you can fry your transmitter by attempting to transmit on it. The SWR could be high from a failed cable to the antenna as example of one reason.
 
Standing wave ratio.
A measure of the amount of transmitted energy reflected back into the radio as opposed to going out of the antenna.
 
Stop trying to transmit on the radio until you have checked the SWR. If the SWR is high you can fry your transmitter by attempting to transmit on it. The SWR could be high from a failed cable to the antenna as example of one reason.
Not unless you still have vacuum tubes in your comm radio. The transistor finals on a low voltage DC supply aren't going to dissipate enough heat to burn up with a mismatch, they just shutdown and emit very little output power.
However, if his radio isn't show ing the T or whatever it does to show it is being keyed, the problem is not an antenna mismatch. Most likley the PTT switch or the wiring between there (including the audio panel) and the radio has an issue.
 
Get a SWR meter, wire it between the radio and antenna wire, hit transmit and look at the reading on the meter. I bought one of these:http://www.hamradio.com/detail.cfm?pid=H0-001257
Not the exact same frequency range but works fine just the same.

I had the same symptoms with my 430 - it would receive but no responses from my transmissions. Upon further investigation, I have very high SWR. In my case, the wire going to the whip antenna in the vertical empennage was not secured well. This allowed the wire to move with turbulence. Over time enough repetitive stress caused internal wire damage.

It doesn't take much to receive on the 430. When you transmit with a broken wire, most of that power is returned to the 430 rather than going out. In my case, with a handheld comm used for testing receive, my transmissions were garbled but present under a hundred feet or so.

If you don't have a SWR meter, you can swap the antenna cables to your comm's and see if the problem follows the swap.
 
You could take it to an avionics shop. They would fix it for you. Ohh wait you already did that so yeah. SWR meter. You should put that on your list of stuff to buy. :p
 
Don't forget to charge the batteries (or have a full spare set if it takes alkalines)...
 
Get a SWR meter, wire it between the radio and antenna wire, hit transmit and look at the reading on the meter. I bought one of these:http://www.hamradio.com/detail.cfm?pid=H0-001257
Not the exact same frequency range but works fine just the same.

I had the same symptoms with my 430 - it would receive but no responses from my transmissions. Upon further investigation, I have very high SWR. In my case, the wire going to the whip antenna in the vertical empennage was not secured well. This allowed the wire to move with turbulence. Over time enough repetitive stress caused internal wire damage.

It doesn't take much to receive on the 430. When you transmit with a broken wire, most of that power is returned to the 430 rather than going out. In my case, with a handheld comm used for testing receive, my transmissions were garbled but present under a hundred feet or so.

If you don't have a SWR meter, you can swap the antenna cables to your comm's and see if the problem follows the swap.
lol -- are you serious?
 
Don't listen to forane. If you're not getting the TX indicator then your problem is before the fact and investigating the antenna match is a waste of time. Seriously forane, look at the symptoms. This is a PTT issue.
 
That's what I get for perusing the ops post while distracted.
Didn't notice the TX light not coming on...
 
Can you revise the thread title to "Nobody will answer me" rather than the incorrect "No body will answer me"? Bodies never answer, except in zombie movies.
 
7a30caa1cca74fce1de6d3593452494e.jpg

I own two of these. I can count the number of times I've seen one needed to troubleshoot an aircraft radio SWR problem in one digit on one hand. The coax was thirty years old.

It'd never be my first recommendation for troubleshooting and in this case, with the PTT not showing, the problem is obviously keying.

OP probably could have continued the flight if the other yoke had a PTT and he plugged into the jacks on the other side, too.
 
I carry a hand held with me on every flight, always within reach. I have two older radios, Narco 12DR and KX170B. A few years ago I had a transponder let out all the smoke, turned master and alternator off. Sure glad I had the hand held landing class D in Juneau.

Who has had to use light signals from the tower to land. I asked the tower to give me light signals one time and they were hard to see.
 
I carry a hand held with me on every flight, always within reach. I have two older radios, Narco 12DR and KX170B. A few years ago I had a transponder let out all the smoke, turned master and alternator off. Sure glad I had the hand held landing class D in Juneau.

Who has had to use light signals from the tower to land. I asked the tower to give me light signals one time and they were hard to see.

When I had to move my headset to the right seat plug I was in a friend's plane; my handheld lives in my plane.

Needed light gun signals once, in a rental 182 with a dead alternator. At night. My handheld was in my plane, I was flying with an instructor in his plane . . . Being dark, the green light was very visible, although we only had 10° flaps out.
 
Not unless you still have vacuum tubes in your comm radio. The transistor finals on a low voltage DC supply aren't going to dissipate enough heat to burn up with a mismatch, they just shutdown and emit very little output power.
However, if his radio isn't show ing the T or whatever it does to show it is being keyed, the problem is not an antenna mismatch. Most likley the PTT switch or the wiring between there (including the audio panel) and the radio has an issue.
Actually the tube finals can stand a way higher standing wave than the solid state. But that isn't the trouble here, unless the finals are already toasted. But with the low power of these radios, a ratio of 3:1 could probably be handled anyway.
I would suspect a faulty PTT, or bad connection.
 
Actually the tube finals can stand a way higher standing wave than the solid state. But that isn't the trouble here, unless the finals are already toasted. But with the low power of these radios, a ratio of 3:1 could probably be handled anyway.
I would suspect a faulty PTT, or bad connection.

I disagree. With a transistor final fed by a constant (14/28V) power supply, it's not going to generate enough power into a mismatch to heat up anything. You can do some real damage to a tube final fed by the T-power or dynamotor or whatever into a mismatch. I worked on mobile radios (had a GE Prog Line in my car for years) for a long time before I made the jump to all-semiconductor radios.
 
If you need a handheld make you have a way to connect to an antenna. I put a coax Junction under the panel a d had a 4' lead for the hand held. Alternator bearings went out in Baja. Came all the way home with just the handheld with a headset adapter. Was talking to TUS from South of the border.
 
I carry a hand held with me on every flight, always within reach. I have two older radios, Narco 12DR and KX170B. A few years ago I had a transponder let out all the smoke, turned master and alternator off. Sure glad I had the hand held landing class D in Juneau.

Who has had to use light signals from the tower to land. I asked the tower to give me light signals one time and they were hard to see.

Tower people rarely get to use the light gun and most don't know how to aim one or remember to raise to shade to do so.
 
7a30caa1cca74fce1de6d3593452494e.jpg

I own two of these. I can count the number of times I've seen one needed to troubleshoot an aircraft radio SWR problem in one digit on one hand. The coax was thirty years old.

It'd never be my first recommendation for troubleshooting and in this case, with the PTT not showing, the problem is obviously keying.

OP probably could have continued the flight if the other yoke had a PTT and he plugged into the jacks on the other side, too.

I cannot believe a GA aircraft will have coax with big fat Type-N connectors, like those on tour Bird meter.
 
I cannot believe a GA aircraft will have coax with big fat Type-N connectors, like those on tour Bird meter.

Usually BNC. I have BNCs that can be installed on the Bird, or just grab a high quality silver plated adapter and at VHF it's not going to be a significant loss or impedance bump.

This particular Bird has other crap installed on it for injecting weak signals but the other one doesn't. This one also has the peak reading mode factory option. (This one was close by when I shot the photo to reply, but it has a specific job -- it's usually used to check real world noise floor against a known signal injected into the lossy injector on various receivers to get pre-amplification levels correct at different locations.)

Or I'd grab one of the many double shielded jumpers around here with different high quality Amphenol ends on the test cable, although I usually don't mess with female connectors on cables -- they can be done with high quality crimp connectors but they're a PITA.

No particular problem handling different connectors 'round here... most of the radios are N but the HF stuff is UHF connectors, and some of the microwave stuff is SMA at low power. High power stuff is almost always N here.

It's about a five minute swap to toss BNCs on the other Bird. If I don't drop a screw and have to hunt on the floor for it. :)
 
OP, any update on the TX issue?
I agree with the guys here that throwing money at an avionics shop is not a good way to diagnose the failure. It could be as simple as the yoke tube cutting the PTT wires.
So has your avionics shop found the problem yet?
 
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