Using a radio with 50KHz spacing

rk

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I have an old COM radio with 50KHz channel spacing in my 1978 Cessna 182. I was talking to a shop about avionics upgrade and they mentioned that the radio might not be legal anymore. Does anyone know more about this?

I almost never transmit using this radio (I have another newer one), so I am not too worried about creating interference in neighboring channels. I am more worried about DPEs taking issue with the radio during checkrides.
 
I have an old COM radio with 50KHz channel spacing in my 1978 Cessna 182. I was talking to a shop about avionics upgrade and they mentioned that the radio might not be legal anymore. Does anyone know more about this?

I almost never transmit using this radio (I have another newer one), so I am not too worried about creating interference in neighboring channels. I am more worried about DPEs taking issue with the radio during checkrides.
I think that is a lot like driving your car with an expired registration. Most of the time you will get away with it. But the DPE will likely look at the plane and its equipment. Seeing a radio capable of operating contra to the FARs installed in the dashboard, is asking for a bust.
-Skip
 
Do you have the FAR that has the requirement? I can't seem to find it.
 
Unless something has changed, perfectly legal to have the radio in the airplane and to use it for receiving.

Depends on the radio if it is legal to transmit, some did transmit on a narrow enough band to still be legal for transmitting. There is probably a list somewhere, but may be easier to check the requirements and technical detail of the radio you have, or simple is just don't transmit with it.

Brian
CFIIG/ASEL
 
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Do you have the FAR that has the requirement? I can't seem to find it.
Not FAA... FCC. List is attached.

FCC says you can't "use" it, whether it still can be "used" as a receiver-only is up to debate, but I suspect the FCC doesn't care.

Ron Wanttaja
 

Attachments

  • FCC Unacceptable Aircraft Radios.pdf
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Not FAA... FCC. List is attached.

FCC says you can't "use" it, whether it still can be "used" as a receiver-only is up to debate, but I suspect the FCC doesn't care.

Ron Wanttaja

Thank you! That's very helpful. It says "There is no requirement for an older radio to be removed from an aircraft in cases where the pilot does not intend to use it to transmit radio signals", so I guess I am good for now :)
 
Thank you! That's very helpful. It says "There is no requirement for an older radio to be removed from an aircraft in cases where the pilot does not intend to use it to transmit radio signals", so I guess I am good for now :)

OK, Rx, I’m wrong. Good luck going forward. Time to stop worrying about that radio. -Skip
 
Thank you! That's very helpful. It says "There is no requirement for an older radio to be removed from an aircraft in cases where the pilot does not intend to use it to transmit radio signals", so I guess I am good for now :)
Thanks, I didn't re-read it closely and missed that clause.

Could always keep it ready for use in case the primary radio craps out. I don't know if the FCC has an equivalent of 14CFR 91.3 ("In an in-flight emergency requiring immediate action, the pilot in command may deviate from any rule of this part to the extent required to meet that emergency."), but the ENFORCEMENT division of the FCC is pretty small; you're not likely to be bothered in that case.

Ron Wanttaja
 
Otherwise, if you can't use it, you could label it "inoperative."
We did that (put an INOP label on it) for my PPL checkride on the ADF equipment. Figured chance of DPE asking me to use it was small but slap an INOP label on it and the chance goes to zero.

I never did learn how to use the ADF and it was later removed in an upgrade.
 
Besides COM radios, did NAV radios also go through a big change years ago, from 50 to 25 kHz spacing?
 
the ENFORCEMENT division of the FCC is pretty small; you're not likely to be bothered in that case.
Right. As a lifelong broadcaster (radio and mostly television), I am quite sure the FCC is not very concerned about this sort of issue. I remember an FCC inspector coming into our lobby and asking to see the radio station chief engineer. "Do you have an appointment?' the receptionist asked.

"I'm from the FCC. I don't NEED an appointment," he replied.

Petty bureaucrats are always interesting. And almost always annoying.
 
They do want you to monitor guard freq when enroute. Nothing like an extra "receive only" radio in your panel for that.
 
Note, that having a 50 khz spacing radio is NOT prohibited. What is prohibited is one that doesn't meet the frequency stability requirements necessary to not bleed over the tighter spacing. Subtle difference.

No, nothing changed with the VOR/LOC band. They remained on the 50 kHz spacing.

Amusingly, years ago I had fairly recent KX155s in my plane (760 channel) and remember getting a handoff from ATC and they asked if I could do that frequency or did I need something easier. I told them that it might be an old aircraft, but it did have modern avionics.
 
Note, that having a 50 khz spacing radio is NOT prohibited. What is prohibited is one that doesn't meet the frequency stability requirements necessary to not bleed over the tighter spacing. Subtle difference.

No, nothing changed with the VOR/LOC band. They remained on the 50 kHz spacing.

Amusingly, years ago I had fairly recent KX155s in my plane (760 channel) and remember getting a handoff from ATC and they asked if I could do that frequency or did I need something easier. I told them that it might be an old aircraft, but it did have modern avionics.
Now that you mention it, are there any 136Mhz frequencies published anywhere?
 
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