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Greg Bockelman

Greg Bockelman

Touchdown! Greaser!
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Greg Bockelman
I had opportunity to check my VORs against a VOT today. One was 6 degrees off, the other was 8 degrees off. I have no intentions of flying the airplane IFR so this is not a big deal as of now. But I WANT to be able to fly it IFR. Technically, since the VORs are within 4 degrees of EACH OTHER, it is legal, but now that I KNOW they are off, there is no way.

Now for the question. How are the VOR receivers adjusted? Is it an adjustment in the head, or is it in the radio?

Also, since I am asking, my glideslope does not wake up until inside the marker. I don't have an external glideslope antenna, as far as I know. FWIW, it has worked properly in the past. I have been told the head is pretty much FUBARed but that was after a verbal discussion, not after any testing. Any ideas?

These are KX 170B's by the way.
 
I have not the slightest clue, but will watch with great interest, as I have wondered the same things.
 
Greg Bockelman said:
I had opportunity to check my VORs against a VOT today. One was 6 degrees off, the other was 8 degrees off. I have no intentions of flying the airplane IFR so this is not a big deal as of now. But I WANT to be able to fly it IFR. Technically, since the VORs are within 4 degrees of EACH OTHER, it is legal, but now that I KNOW they are off, there is no way.

Now for the question. How are the VOR receivers adjusted? Is it an adjustment in the head, or is it in the radio?

Also, since I am asking, my glideslope does not wake up until inside the marker. I don't have an external glideslope antenna, as far as I know. FWIW, it has worked properly in the past. I have been told the head is pretty much FUBARed but that was after a verbal discussion, not after any testing. Any ideas?

These are KX 170B's by the way.
Click to expand...

The one place the problem cannot be is in the KX170B. Where the adjustment needs to be made could be in the OBS or in the nav converter (which may or may not be in the OBS head). If you have separate nav converters (KN-72) the adjustment is a small screw accessible through the front panel of the converter. If the nav converter is built into the CDI/OBS I suspect the adjustment is inside. What kind of CDI/OBS do you have?
 
SCCutler said:
I have not the slightest clue, but will watch with great interest, as I have wondered the same things.
Click to expand...

This. I too was waiting for...

gismo said:
The one place the problem cannot be is in the KX170B. Where the adjustment needs to be made could be in the OBS or in the nav converter (which may or may not be in the OBS head). If you have separate nav converters (KN-72) the adjustment is a small screw accessible through the front panel of the converter. If the nav converter is built into the CDI/OBS I suspect the adjustment is inside. What kind of CDI/OBS do you have?
Click to expand...

I knew there an adjustment of a little screw somewhere. I have the KN converter, too, but I have TKM MX170 radios.

Is that adjusting a clock sync, Lance?
 
mikea said:
This. I too was waiting for...



I knew there an adjustment of a little screw somewhere. I have the KN converter, too, but I have TKM MX170 radios.

Is that adjusting a clock sync, Lance?
Click to expand...

Nope, IIRC it's a RC phase delay. I'm working from a memory of adjusting one a few years ago but I think it's labeled on the KN-72 and I think it's behind a hole on the front of the unit.
 
Greg Bockelman said:
KI 214 I believe for the LOC/GS. Not sure on the other.
Click to expand...

I'm fairly certain that the KI 214 contains the VOR/LOC converter so the problem has to be in it. Sometimes the actual problem is that the card that shows the OBS setting has slipped mechanically. This is probably something for a CRS to handle.
 
Rotor&Wing said:
The only way to legally and properly adjust these are on an avionics bench.
Click to expand...

I think Greg's original question was about what to take to the avionics shop. Of course, as a pilot the only thing he can legally re-install in the plane himself is the radio which isn't where the problem lies.
 
gismo said:
I think Greg's original question was about what to take to the avionics shop. Of course, as a pilot the only thing he can legally re-install in the plane himself is the radio which isn't where the problem lies.
Click to expand...

Take the airplane to the avionics shop. Just removing the indicator and the radio for bench check may or may not solve the problem. Corroded antenna connectors, corrosion beneath an antenna, faulty grounds, etc can be root causes for other problems.
 
Rotor&Wing said:
Take the airplane to the avionics shop. Just removing the indicator and the radio for bench check may or may not solve the problem. Corroded antenna connectors, corrosion beneath an antenna, faulty grounds, etc can be root causes for other problems.
Click to expand...

None of the problems you listed would cause a consistent 6 degree error.
 
gismo said:
I think Greg's original question was about what to take to the avionics shop. Of course, as a pilot the only thing he can legally re-install in the plane himself is the radio which isn't where the problem lies.
Click to expand...

That's just not true either.

Jim
 
SCCutler said:
Jim:

Please, tell us more (not snarking, really want to know, as this is a question I have had myself).

Thanks in advance.
Click to expand...

The maintenance regulations (primarily 47CFR43) and the Bible can be used to prove or disprove anything you wish. And, like the Bible, the FAR was written when dinosaurs roamed the earth. Radios? We don't need no steenking radios.

The point being, an "appliance major repair" is limited to 5 items ... calibration of instruments, calibration of radios, disassembly of complex hydraulic valves, and overhaul of pressure carburetors.

So the question becomes, is ADJUSTING the screw on the back of the nav head an ADJUSTMENT or a CALIBRATION. Since the FAR is silent on how to deal with this issue, we need to turn elsewhere. That elsewhere can be other FAA publications or, as a last resort, the dictionary.

In this case the dictionary comes up way short, so we turn to see if any other publication deals with the issue (more later). Sadly, it is not well defined.

So we turn to the industry, where I have resided for the last fifty years. When we say "calibration", we mean a nose-to-toes alignment of the entire system. Merely turning up a volume control or adjusting the squelch, or in this case tweaking an easily accessible and plainly labeled control to center the needle is an adjustment, not a calibration. Nor is it a "radio" in the strictest terms. A radio is an appliance that allows communications to take place on the radio waves. That nav head could no more be called a radio than a Chevy be called a Cessna.

So where do we draw the line between MAJOR and MINOR repairs? Ah, the FAA has dealt with this issue smack on. In a document called "Plane Sense" published by the FAA Western Region some thirty years ago, the judgment call between major and minor IS IN THE HANDS OF THE PERSON PERFORMING THE WORK. Where it is not SPECIFIC in the FAR, the FAA grants wide latitude to the person performing the work.

Similarly, the FAR is silent when it comes to removal and replacement of an identical part onto the airplane. Identical meaning make, model, and serial number. Simple removal and replacement are not specifically spoken to, so again we rely on the person doing the work. Harry Hamhand may not be qualified to blow his nose in an airplane, but a person who has been working in and around airplanes since Christ was a Seaman Deuce may be more qualified than any of us to rassle an instrument out, take it for repair to a duly qualified & certificated person, and reinstall it. The fact that the FAA has chosen not to update the preventive maintenance part of the FAR in fifty some years is no reason for us not to look at the spirit of the regs if the letter of the regs is silent.

Of course, nothing I say will prevent some eager beaver FAA puke from jamming it up your hiney if he or she feels like it. Just do it and shut up about it.

Jim
 
Jim, that post was all-et-up with common sense. Thanks.

/s/ Spike
 
weirdjim said:
The maintenance regulations (primarily 47CFR43) and the Bible can be used to prove or disprove anything you wish. And, like the Bible, the FAR was written when dinosaurs roamed the earth. Radios? We don't need no steenking radios.

The point being, an "appliance major repair" is limited to 5 items ... calibration of instruments, calibration of radios, disassembly of complex hydraulic valves, and overhaul of pressure carburetors.

So the question becomes, is ADJUSTING the screw on the back of the nav head an ADJUSTMENT or a CALIBRATION. Since the FAR is silent on how to deal with this issue, we need to turn elsewhere. That elsewhere can be other FAA publications or, as a last resort, the dictionary.

In this case the dictionary comes up way short, so we turn to see if any other publication deals with the issue (more later). Sadly, it is not well defined.

So we turn to the industry, where I have resided for the last fifty years. When we say "calibration", we mean a nose-to-toes alignment of the entire system. Merely turning up a volume control or adjusting the squelch, or in this case tweaking an easily accessible and plainly labeled control to center the needle is an adjustment, not a calibration. Nor is it a "radio" in the strictest terms. A radio is an appliance that allows communications to take place on the radio waves. That nav head could no more be called a radio than a Chevy be called a Cessna.

So where do we draw the line between MAJOR and MINOR repairs? Ah, the FAA has dealt with this issue smack on. In a document called "Plane Sense" published by the FAA Western Region some thirty years ago, the judgment call between major and minor IS IN THE HANDS OF THE PERSON PERFORMING THE WORK. Where it is not SPECIFIC in the FAR, the FAA grants wide latitude to the person performing the work.

Similarly, the FAR is silent when it comes to removal and replacement of an identical part onto the airplane. Identical meaning make, model, and serial number. Simple removal and replacement are not specifically spoken to, so again we rely on the person doing the work. Harry Hamhand may not be qualified to blow his nose in an airplane, but a person who has been working in and around airplanes since Christ was a Seaman Deuce may be more qualified than any of us to rassle an instrument out, take it for repair to a duly qualified & certificated person, and reinstall it. The fact that the FAA has chosen not to update the preventive maintenance part of the FAR in fifty some years is no reason for us not to look at the spirit of the regs if the letter of the regs is silent.

Of course, nothing I say will prevent some eager beaver FAA puke from jamming it up your hiney if he or she feels like it. Just do it and shut up about it.

Jim
Click to expand...

I pretty much agree with all you posted here but I didn't see anything that would allow a pilot (with no A&P) replace a nav head in a certified airplane and then prepare and sign a log entry covering the work and subsequent return to service of the airplane. FAR 43/A is pretty clear that only tray mounted radios in the panel (excluding DME and XPNDR IIRC) can be replaced by a pilot.
 
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gismo said:
None of the problems you listed would cause a consistent 6 degree error.
Click to expand...

Uh huh, right. I'm not going to argue the point, do as you wish.

BTW, my background and training was Avionics specializing in Communication, Navigation and Radar.
 
weirdjim said:
The maintenance regulations (primarily 47CFR43) and the Bible can be used to prove or disprove anything you wish. And, like the Bible, the FAR was written when dinosaurs roamed the earth. Radios? We don't need no steenking radios.

The point being, an "appliance major repair" is limited to 5 items ... calibration of instruments, calibration of radios, disassembly of complex hydraulic valves, and overhaul of pressure carburetors.

So the question becomes, is ADJUSTING the screw on the back of the nav head an ADJUSTMENT or a CALIBRATION. Since the FAR is silent on how to deal with this issue, we need to turn elsewhere. That elsewhere can be other FAA publications or, as a last resort, the dictionary.

In this case the dictionary comes up way short, so we turn to see if any other publication deals with the issue (more later). Sadly, it is not well defined.

So we turn to the industry, where I have resided for the last fifty years. When we say "calibration", we mean a nose-to-toes alignment of the entire system. Merely turning up a volume control or adjusting the squelch, or in this case tweaking an easily accessible and plainly labeled control to center the needle is an adjustment, not a calibration. Nor is it a "radio" in the strictest terms. A radio is an appliance that allows communications to take place on the radio waves. That nav head could no more be called a radio than a Chevy be called a Cessna.

So where do we draw the line between MAJOR and MINOR repairs? Ah, the FAA has dealt with this issue smack on. In a document called "Plane Sense" published by the FAA Western Region some thirty years ago, the judgment call between major and minor IS IN THE HANDS OF THE PERSON PERFORMING THE WORK. Where it is not SPECIFIC in the FAR, the FAA grants wide latitude to the person performing the work.

Similarly, the FAR is silent when it comes to removal and replacement of an identical part onto the airplane. Identical meaning make, model, and serial number. Simple removal and replacement are not specifically spoken to, so again we rely on the person doing the work. Harry Hamhand may not be qualified to blow his nose in an airplane, but a person who has been working in and around airplanes since Christ was a Seaman Deuce may be more qualified than any of us to rassle an instrument out, take it for repair to a duly qualified & certificated person, and reinstall it. The fact that the FAA has chosen not to update the preventive maintenance part of the FAR in fifty some years is no reason for us not to look at the spirit of the regs if the letter of the regs is silent.

Of course, nothing I say will prevent some eager beaver FAA puke from jamming it up your hiney if he or she feels like it. Just do it and shut up about it.

Jim
Click to expand...

Bottom line. This needs to go to an avionics shop to be legally done and legally signed off.

Is it really that difficult?
 
Rotor&Wing said:
Uh huh, right. I'm not going to argue the point, do as you wish.

BTW, my background and training was Avionics specializing in Communication, Navigation and Radar.
Click to expand...
I'm with Lance on this one. A consistent 6 degree error won't be caused by the potential problems you described. That just doesn't make any sense. My background is not in Avionics, or Communication, or Navigation, or Radar.

Perhaps you could give a technical reason as to exactly how a poor antenna connection would cause the CDI to display a consistent 6 degree error? If so, I'd really be interested, I'm just an amateur and always looking to learn :)
 
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jesse said:
I'm with Lance on this one. A consistent 6 degree error won't be caused by the potential problems you described. That just doesn't make any sense. My background is not in Avionics, or Communication, or Navigation, or Radar.

Perhaps you could give a technical reason as to exactly how a poor antenna connection would cause the CDI to display a consistent 6 degree error? If so, I'd really be interested, I'm just an amateur and always looking to learn :)
Click to expand...

Re-read Greg's post on the problems. When I did work as an avionics tech it was always fun having the owners second guess the techs to try to prove us wrong.

There's lots of fine books on the subject. Enjoy. :wink2:
 
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Rotor&Wing said:
There's lots of fine books on the subject. Enjoy. :wink2:
Click to expand...
I'm sure there are..and I've read some myself. I'm not a complete radio or electronics idiot and I believe firmly in understanding something before I believe in it. Obviously you can't give a technical explanation.

I was just looking to learn since you seemed to know the fix.
 
gismo said:
I pretty much agree with all you posted here but I didn't see anything that would allow a pilot (with no A&P) replace a nav head in a certified airplane and then prepare and sign a log entry covering the work and subsequent return to service of the airplane. FAR 23/A is pretty clear that only tray mounted radios in the panel (excluding DME and XPNDR IIRC) can be replaced by a pilot.
Click to expand...

Would you be a little more specific about what you mean by FAR 23/A? I don't believe I've ever seen that exact reg.

Jim
 
Rotor&Wing said:
Uh huh, right. I'm not going to argue the point, do as you wish.

BTW, my background and training was Avionics specializing in Communication, Navigation and Radar.
Click to expand...

Unfortunately, the OP is correct. Phase error at low frequency audio isn't going to be affected by a sloppy antenna. As a matter of fact, on most all light singles, there is only one NAV antenna and everything (both nav receivers and the glideslope) are split off that one signal. Equally.

My background in avionics was at the tender age of 16 I started repairing superhomers in return for flight lessons. Illegal? Probably, but the statute of limitations ran out several dozen years ago. I graduated to the airlines to put myself through college and then founded an avionics company that is in its 36th year.

But I sure have a lot to learn about this business.

Jim
 
Rotor&Wing said:
Bottom line. This needs to go to an avionics shop to be legally done and legally signed off.

Is it really that difficult?
Click to expand...


It is the guts of the discussion.

If it is an adjustment that can be made in situ, then it does NOT (repeat NOT) have to go to the avionics shop.

If it is a flaw in the nav head itself, I agree that only a certificated avionics shop can repair and sign off on it.

The question of who takes it out of the airplane, takes it to the shop, gets it fixed, and puts it back in the airplane, I guess you and I have a fundamental difference of opinion.

I didn't notice your sig. A&P IA?

Jim
 
Rotor&Wing said:
Bottom line. This needs to go to an avionics shop to be legally done and legally signed off.

Is it really that difficult?
Click to expand...

Rotor&Wing said:
Re-read Greg's post on the problems. When I did work as an avionics tech it was always fun having the owners second guess the techs to try to prove us wrong.

There's lots of fine books on the subject. Enjoy. :wink2:
Click to expand...

Assuming you can find an avionics shop that will do the work properly, promptly, and cost-effectively. Unfortunately, IME, it pays for the customer to know what they are talking about when having a conversation with the shop. Tends to allow said customer to sort out the qualified from the charlatan.... and lets the shop know that the customer has done/is willing to do some homework.

My track record with avionics shops is not very good (including one that removed during install of other new equipment -as in "stole" - my almost-new remote gyro and replaced it with a "nearly dead" reject full of "radio shack consumer parts"... causing my HSI to lose sync and drift 45 degrees one day in IFR departing Four Corners), and I've spent a lot of money having having to get other shops to fix problems caused by shops that should have been qualified. I am not alone with those issues.

I won't bore you with my qualifications or experiences. Suffice it to say that I'd trust Lance before I trusted a new avionics shop. And that's also not to say that I'd advocate doing anything illegally.
 
weirdjim said:
It is the guts of the discussion.

If it is an adjustment that can be made in situ, then it does NOT (repeat NOT) have to go to the avionics shop.

If it is a flaw in the nav head itself, I agree that only a certificated avionics shop can repair and sign off on it.

The question of who takes it out of the airplane, takes it to the shop, gets it fixed, and puts it back in the airplane, I guess you and I have a fundamental difference of opinion.

I didn't notice your sig. A&P IA?

Jim
Click to expand...

Yes, A&P/IA.

Please show me in the regs, or anywhere for that matter where a non licensed individual can calibrate and/or adjust a navigation device. Also show me where a non licensed individual can remove the nav head to make the adjustment and re-install without a required part 43 logbook entry.

All this "word game" playing is rather silly.

The simple way to fix this problem is to take the damn thing to an avionics shop and have it fixed properly rather than trying the "shade tree" avionics tech method, especially if you are going to be flying this aircraft IFR.

Never ceases to amaze me the cheapness of aircraft owners (not directed at you Greg). If you can't afford to properly maintain the aircraft and equipment you shouldn't have it in the first place.
 
Rotor&Wing said:
Yes, A&P/IA.

Please show me in the regs, or anywhere for that matter where a non licensed individual can calibrate and/or adjust a navigation device. Also show me where a non licensed individual can remove the nav head to make the adjustment and re-install without a required part 43 logbook entry.

All this "word game" playing is rather silly.

The simple way to fix this problem is to take the damn thing to an avionics shop and have it fixed properly rather than trying the "shade tree" avionics tech method, especially if you are going to be flying this aircraft IFR.

Never ceases to amaze me the cheapness of aircraft owners (not directed at you Greg). If you can't afford to properly maintain the aircraft and equipment you shouldn't have it in the first place.
Click to expand...

And to my point: it's not always about money. It's about quality and reliability. There are some "shade tree" guys I'd pay LONG before I'd take it to an expensive shop. And there are both "shade tree" and "shop" guys I'd avoid like the plague. The trick is figuring out which is which....

Side note: for many years Narco maintained a posture of "factory repair is best" and refused to help even avionics shops. Their factory facility got a really bad reputation.... to the point that a LOT of folks will never deal with Narco again. They were cheaper than some shops, but the quality, reliability, and responsiveness wasn't there.
 
wsuffa said:
Assuming you can find an avionics shop that will do the work properly, promptly, and cost-effectively. .............

My track record with avionics shops is not very good ..................

I won't bore you with my qualifications or experiences. Suffice it to say that I'd trust Lance before I trusted a new avionics shop. And that's also not to say that I'd advocate doing anything illegally.
Click to expand...

So, one shop rips you off and that makes all shops suspect?

You can go get Joe Blow the greatest IT ever to trouble shoot your avionics, but without proper and required manuals and data, and some sort of certification it will do you no good.
 
Rotor&Wing said:
So, one shop rips you off and that makes all shops suspect?

You can go get Joe Blow the greatest IT ever to trouble shoot your avionics, but without proper and required manuals and data, and some sort of certification it will do you no good.
Click to expand...


One? If it were only one, no big deal. It's multiple shops. In multiple cities. And it's not just me - I've seen plenty of planes with real rats-nests of wiring and badly installed stuff.

I pose a theory that A&P/IA shops have a much better reputation than avionics shops.
 
wsuffa said:
One? If it were only one, no big deal. It's multiple shops. In multiple cities. And it's not just me - I've seen plenty of planes with real rats-nests of wiring and badly installed stuff.

I pose a theory that A&P/IA shops have a much better reputation than avionics shops.
Click to expand...

And to counter that I know of some real first class avionics shops that do top quality work. Of course, it will cost you, but you get what you pay for.
 
weirdjim said:
Unfortunately, the OP is correct. Phase error at low frequency audio isn't going to be affected by a sloppy antenna. As a matter of fact, on most all light singles, there is only one NAV antenna and everything (both nav receivers and the glideslope) are split off that one signal. Equally.

My background in avionics was at the tender age of 16 I started repairing superhomers in return for flight lessons. Illegal? Probably, but the statute of limitations ran out several dozen years ago. I graduated to the airlines to put myself through college and then founded an avionics company that is in its 36th year.

But I sure have a lot to learn about this business.

Jim
Click to expand...

Owner takes his radios out of the plane and walks them to the avionics shop for a bench test. Shop realigns the receiver and gives back to the owner, owner reinstalls into his aircraft. Now the owner finds out he has another problem (weak receive) and calls avionics shop complaining that the shop has caused the problem "because they worked on it".

Owner brings airplane to the shop where the shop now finds 40 year old coax cable and corroded BNC connectors. Shop tells owner the estimate for repairing and owner blows a gasket and demands since the shop worked on the radio then they are required to perform "warranty work".

This is why many shops will not take walk in work from unknown customers. If you want the job done correctly, then the whole aircraft needs to be there so the shop can function test the system in the airplane, then make the necessary adjustments.

But of course you being an avionics tech would know this, right?
 
Jeez, guys. Some of you are inferring a lot from my questions. They were just questions about what might be the problem and what might be involved in fixing them. I NEVER said that I was going to do it.

There are too many failure points in an installation for me to just take the radios to a shop. From the antennas all the way to the radio, from the generator through the CBs to the radio. And on and on. It is a complete system and needs to be troubleshot as such.
 
Rotor&Wing said:
And to counter that I know of some real first class avionics shops that do top quality work. Of course, it will cost you, but you get what you pay for.
Click to expand...

There are, and I don't hesitate to use them. Unfortunately, there's often no good way to know.

Perhaps if the industry were to shun or make known who the losers are it wouldn't be necessary to blame the customer (or potential customer) now, would it? One bad apple spoils....
 
weirdjim said:
Would you be a little more specific about what you mean by FAR 23/A? I don't believe I've ever seen that exact reg.

Jim
Click to expand...

Sorry that was a combination of a typo and nonstandard nomenclature. I was referring to Part 43 Appendix A, the description of what a pilot can do maintenance wise on his own. The reference was supposed to be 43/A not 23/A.
 
Greg Bockelman said:
Jeez, guys. Some of you are inferring a lot from my questions. They were just questions about what might be the problem and what might be involved in fixing them. I NEVER said that I was going to do it.

There are too many failure points in an installation for me to just take the radios to a shop. From the antennas all the way to the radio, from the generator through the CBs to the radio. And on and on. It is a complete system and needs to be troubleshot as such.
Click to expand...

Exactly Greg. Hope you have a good shop nearby that can help you out. :wink2:
 
Rotor&Wing said:
Yes, A&P/IA.

Please show me in the regs, or anywhere for that matter where a non licensed individual can calibrate and/or adjust a navigation device. Also show me where a non licensed individual can remove the nav head to make the adjustment and re-install without a required part 43 logbook entry.
Click to expand...

Isn't that just for Certified aircraft?

Tim
 
Rotor&Wing said:
Yes, A&P/IA.

Please show me in the regs, or anywhere for that matter where a non licensed individual can calibrate and/or adjust a navigation device. Also show me where a non licensed individual can remove the nav head to make the adjustment and re-install without a required part 43 logbook entry.

All this "word game" playing is rather silly.

The simple way to fix this problem is to take the damn thing to an avionics shop and have it fixed properly rather than trying the "shade tree" avionics tech method, especially if you are going to be flying this aircraft IFR.

Never ceases to amaze me the cheapness of aircraft owners (not directed at you Greg). If you can't afford to properly maintain the aircraft and equipment you shouldn't have it in the first place.
Click to expand...

I specifically said that calibration was off limits. I continue to contend that a simple adjustment can be done by anybody that knows what they are doing, licensed, certificated, or blessed.

"Word game" is how civilized individuals carry on a difference of opinion.

The "simple way" to fix this problem depends on whether you have more time than money or more money than time. If you have time, you learn how to do simple noncritical things yourself and save the money for the really difficult or critical tasks. And, the OP specifically said that the airplane wasn't going to go IFR intentionally.

A synonym for "cheap" is "thrifty".

Jim
 
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