1346w Posted October 29, 2020 Report Posted October 29, 2020 I've tried to do my due diligence, but have come up short... My radios "collins 251" have really loud static for about 5-10 minutes after start up. Ground control can't hear me, but I can hear transmissions just fine. After that 5-10 minute period, the static gets extremely loud then goes away completely. ATC can then hear me loud and clear. My question is, can static electricity build up while an airplane is just sitting, then discharge abruptly? And would static wicks help discharge while sitting still? Quote
MikeOH Posted October 29, 2020 Report Posted October 29, 2020 Highly doubt static has anything to do with your problem. You mention radios, as in plural, so this likely not an issue with the radio itself. I'm reasoning that it's an antenna or coax problem. How old are those items? Could be corrosion on connectors. How high is the humidity? Is it 'wetter' than typical? Quote
carusoam Posted October 29, 2020 Report Posted October 29, 2020 Welcome back to the world of analog radios... You are describing a warming up process.... Has anything changed because it has gotten colder outside? If this happened in flight... sure, static build up would be possible... Not moving through dry air, at a high rate of speed... or being impacted by snow.... probably not static build up... It could be the radio aging... a component like a capacitor going bad... or it Could be something else going through the aging process... and your radio picking up the interference... A few ways to determine what it is, and isn’t... or start moving towards some digital electronics... How old are the Collins radios? Its quite possible you have got your money’s worth out of them... Do you have a portable radio..? This way you have a method of getting started while your radios are warming up... Best regards, -a- 1 Quote
MikeOH Posted October 29, 2020 Report Posted October 29, 2020 9 minutes ago, carusoam said: Welcome back to the world of analog radios... You are describing a warming up process.... Has anything changed because it has gotten colder outside? If this happened in flight... sure, static build up would be possible... Not moving through dry air, at a high rate of speed... or being impacted by snow.... probably not static build up... It could be the radio aging... a component like a capacitor going bad... or it Could be something else going through the aging process... and your radio picking up the interference... A few ways to determine what it is, and isn’t... or start moving towards some digital electronics... How old are the Collins radios? Its quite possible you have got your money’s worth out of them... Do you have a portable radio..? This way you have a method of getting started while your radios are warming up... Best regards, -a- If the OP had said, "radio" singular, I'd agree. If he's having the issue on BOTH radios, that's too much coincidence for me to think the problem is within the radio itself. 1 Quote
1346w Posted October 29, 2020 Author Report Posted October 29, 2020 27 minutes ago, MikeOH said: Highly doubt static has anything to do with your problem. You mention radios, as in plural, so this likely not an issue with the radio itself. I'm reasoning that it's an antenna or coax problem. How old are those items? Could be corrosion on connectors. How high is the humidity? Is it 'wetter' than typical? Both radios have the same static, both have separate com antennas. Coax looks in okay shape, but it's definitely old. Quote
1346w Posted October 29, 2020 Author Report Posted October 29, 2020 13 minutes ago, carusoam said: Welcome back to the world of analog radios... You are describing a warming up process.... Has anything changed because it has gotten colder outside? If this happened in flight... sure, static build up would be possible... Not moving through dry air, at a high rate of speed... or being impacted by snow.... probably not static build up... It could be the radio aging... a component like a capacitor going bad... or it Could be something else going through the aging process... and your radio picking up the interference... A few ways to determine what it is, and isn’t... or start moving towards some digital electronics... How old are the Collins radios? Its quite possible you have got your money’s worth out of them... Do you have a portable radio..? This way you have a method of getting started while your radios are warming up... Best regards, -a- "Warm up" is kinda what I was thinking, but it's progressively getting worse. New radios are the last thing I was hoping to hear... Quote
MikeOH Posted October 29, 2020 Report Posted October 29, 2020 2 minutes ago, 1346w said: Both radios have the same static, both have separate com antennas. Coax looks in okay shape, but it's definitely old. Hmm, separate antennas.... have you tried turning off one radio at a time when first starting? Can you confirm the failure to be heard is true regardless of which radio you transmit on? Has the weather become more humid since you started having this problem? Has it gradually become worse, or was it something that 'just happened' one day? Quote
carusoam Posted October 29, 2020 Report Posted October 29, 2020 Let the fun begin... Turn on one radio at a time to determine if it is the radio itself making noise... Turn everything else off... It could be something else going through a warm up process... the radio can be affected by the noises coming out of all the other devices... I had a Narco radio that was great at killing the reception of my GPS... When tuned to specific nav stations... Who mentioned new radios... were not Rockefeller’s ya know.... Is this your first cold snap with these radios? You may get a warm day coming up... test your radios then... use a stop watch on your phone... to see if temp affects the warm up process... Plug a heater in... warm the cabin... do the same thing... You are only trying to prove analog things need a Warm up period... the sooner they warm up, the sooner you get going... Once they are working now? What happens when you shut them down...? If you start them up again do you go through the whole warm up cycle...? Try finding somebody with the same Collins radios... swap in a different one... Did I mention there is a PRE-FLOWN Garmin 430W listed for sale around here... It is the oldest most direct route to modern Nav/Coms... Plus there are quite a few other digital nav coms for a lot less without GPS in them... As a PP, you probably have the skills required to determine if... the radios themselves are responsible for the noise... Something else is making the noise... What the source is... How long the noise takes to go away... How long it takes after shut down, for the noise to come back... Once it warms up, does the noise stay gone... For fun, see what a radio like the one you have is selling for on eBay... There is a certain part of the experimental world that will keep all radios alive for eternity... you might even find a resource for somebody that services these things... In the world of ancient avionics... Collins was pretty good for a long time... Narco was way below them.... Best regards, -a- Quote
carusoam Posted October 29, 2020 Report Posted October 29, 2020 After you review which direction you are going... Edit your title... You are hearing static on your radio... Static discharge is something completely different... I thought we were going to be discussing the near useless static wicks... Static noise during warm-up - Collins radios... This Would get you much closer to a solution from a casual observer in the neighborhood... It may take months for somebody with Collins experience to happen into this thread... Best regards, -a- Quote
carusoam Posted October 29, 2020 Report Posted October 29, 2020 Did you mention... How new these radios are to you? As in they could be aging terribly slowly and may go on like this for years... After you review which direction you are going... Edit your title... You are hearing static on your radio... Static discharge is something completely different... I thought we were going to be discussing the near useless static wicks... Static noise during warm-up - Collins radios... Or maybe... Collins radio experience.... is this normal? This Would get you much closer to a solution from a casual observer in the neighborhood... It may take months for somebody with Collins experience to happen into this thread... Best regards, -a- Yellow tagged... $900. https://www.bennettavionics.com/vhf-251-comm-transceiver/ That thing is Comm only... they use a big word like transceiver... so you know it does two things... broadcasts and receives.... Quote
EricJ Posted October 29, 2020 Report Posted October 29, 2020 There are some aging components somewhere that are causing that, and the warm-up cycle just makes them noisy. It could be in either or both radios or the audio panel, would be my guess, or if you have a separate intercom box, potentially in that, too. It is not static electricity, especially if the airplane has been sitting when this cycle starts. When I first bought my airplane I would have all kinds of comm problems when it was first turned on and it sometimes took 10-20 minutes for it to settle down. I swapped out the audio panel (an ancient King KMA 20) for another one I'd bought on ebay and it got a lot better, but didn't go away completely. This is the curse of old electronic equipment, especially if it has electrolytic capacitors inside. They don't age well. 1 Quote
carusoam Posted October 29, 2020 Report Posted October 29, 2020 Where the word ‘static’ comes from and why TVs would get ‘snow’ all over the display... The tuning knobs were variable capacitors that increased, or decreased capacitance as the knob was turned... The knob was changing relationships between small charged ‘plates’... A little bit of dust between the plates caused all kinds of ‘noise’... So the word static electricity on plates was related to the ‘static’ sound.... and similarly caused static snow on the screen... You would probably have to have a TV From the seventies To appreciate this... PP thoughts only, not an electronics engineer... Best regards, -a- Quote
N201MKTurbo Posted October 29, 2020 Report Posted October 29, 2020 It’s possible the noise is coming through your electrical power system. You say the noise is after start up. Does the noise happen with the engine off? Does the noise go away if you pull the field breaker? 3 Quote
1346w Posted October 29, 2020 Author Report Posted October 29, 2020 8 hours ago, carusoam said: Let the fun begin... Turn on one radio at a time to determine if it is the radio itself making noise... Turn everything else off... It could be something else going through a warm up process... the radio can be affected by the noises coming out of all the other devices... I had a Narco radio that was great at killing the reception of my GPS... When tuned to specific nav stations... Who mentioned new radios... were not Rockefeller’s ya know.... Is this your first cold snap with these radios? You may get a warm day coming up... test your radios then... use a stop watch on your phone... to see if temp affects the warm up process... Plug a heater in... warm the cabin... do the same thing... You are only trying to prove analog things need a Warm up period... the sooner they warm up, the sooner you get going... Once they are working now? What happens when you shut them down...? If you start them up again do you go through the whole warm up cycle...? Try finding somebody with the same Collins radios... swap in a different one... Did I mention there is a PRE-FLOWN Garmin 430W listed for sale around here... It is the oldest most direct route to modern Nav/Coms... Plus there are quite a few other digital nav coms for a lot less without GPS in them... As a PP, you probably have the skills required to determine if... the radios themselves are responsible for the noise... Something else is making the noise... What the source is... How long the noise takes to go away... How long it takes after shut down, for the noise to come back... Once it warms up, does the noise stay gone... For fun, see what a radio like the one you have is selling for on eBay... There is a certain part of the experimental world that will keep all radios alive for eternity... you might even find a resource for somebody that services these things... In the world of ancient avionics... Collins was pretty good for a long time... Narco was way below them.... Best regards, -a- So the radios are mid 70s era, I've owned the plane for almost two years and the same radios in this airplane for at least 30 years. I did do a little more research this morning and the static is still there with the engine off and nothing but the radios powered on. I'm in Colorado, so it's been pretty dry here with the exception of snow a few days ago. I've got a extra radio on the self and I've tried swapping them out, moving radios top to bottom in the stack, but always the same outcome... 8 hours ago, carusoam said: Welcome back to the world of analog radios... You are describing a warming up process.... Has anything changed because it has gotten colder outside? If this happened in flight... sure, static build up would be possible... Not moving through dry air, at a high rate of speed... or being impacted by snow.... probably not static build up... It could be the radio aging... a component like a capacitor going bad... or it Could be something else going through the aging process... and your radio picking up the interference... A few ways to determine what it is, and isn’t... or start moving towards some digital electronics... How old are the Collins radios? Its quite possible you have got your money’s worth out of them... Do you have a portable radio..? This way you have a method of getting started while your radios are warming up... Best regards, -a- "Warm up" 1 Quote
PT20J Posted October 29, 2020 Report Posted October 29, 2020 So, you have eliminated the charging system, the ignition system and the radios. That leaves the audio panel. Skip 2 Quote
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