Radio Reception Issues

[GeorgeMJ]

An update: First, my 2016 has an HD radio. For right now I'm testing with the HD off as more bandwidth is required for HD reception and I'm hoping performance may be better for FM with the HD off. Testing is done on non HD stations or analog FM from an HD station only. The more testing I do the worse it is looking for the GM radio.

 

My 2001 test radio on the 2016 antenna showed poor results. I have to investigate that a little more.

 

I took a 2008 Chevy truck for a ride through my bad signal area and the radio performed well. I would have no complaints with the 2008 truck radio. I also took a 2002 Cavalier through the same area with the same results, excellent radio and good reception. Then I took my 2016 through the same area, nowhere near as good as those two.

Today I rode in a 2014 Ford Explorer. In my opinion after testing on weak stations, it had good FM reception and evidence of automatic bandwidth and tone adjustment to reduce noise. The AM reception on the Ford radio in my opinion was rather poor.

 

Under the latest radio manufacturer guidelines, the radio should adjust bandwidth and tone to minimize the effect of multipath and hiss on FM. I think this is where the older radios were superior. If you did have a weak signal that caused the swishing and static sound, the radio adjusted itself, bandwidth and tone, so it wasn't that objectionable. The 2016 Chevy radio appears to do none of that and allows constant high frequency swishing with multipath and static from weak signals. It had multipath sounding distortion while sitting in a good signal area where three other GM vehicles, 2002 Cavalier, 2008 Chevy truck and 2000 Buick Lesabre, in the same proximity, had no evidence of multipath distortion and sunded clean. Disappointing, and not the Delco quality that I've been used to, and certainly not something you would expect in such a pricey vehicle. I plan to test the sensitivity next if I can.

 

I had a friend hold an aftermarket antenna with a shorter cable adjusted to be the same length as the 2016 Chevy truck antenna out near the end of the passenger side mirror, as far as it would reach. This new antenna measured 70 pF as compared to the 2016 antenna at 170 pF and the performance of the radio appeared to be worse. Seems to point to the 2016 antenna being matched to the 2016 radio.

 

More later.

[tnchevy]

Was doing some work around the my house over the weekend and had my $10 AM/FM alarm clock radio on. My truck is parked 10 feet away so I figured I would do a little testing on my own. The $10 wallyworld special has a much clearer sound and picked up more stations than my truck. Very sad.

[Ron.s]

My 2014 radio had weak FM reception but my 2016 is better than normal. Subjective assessment comparing it to other vehicles I have owned. I get a decent FM signal 120 miles away and don't lose the signal in areas where my 2014 went to static.

[GeorgeMJ]

I had a chance to measure the sensitivity of my 2016 Silverado Mylink radio on FM today. Results are pretty bad when comparing to other radios. More details when I get a chance to write them. If you are familiar with new aftermarket radio sensitivity specifications, the best are 7 to 8 dBf, (dB above a femtoWatt, more later), my Mylink radio measured 14.6 dBf for 20dB of FM quieting, (actually won't make 20dB, only made 19). My '64 Cutlass with a Spark O Matic FM converter is better than that! I will lay out the measurements on several radios later.

[WLC]

E-mailed GM again about radios. See what happens!

[SierraMyst]

An update: First, my 2016 has an HD radio. For right now I'm testing with the HD off as more bandwidth is required for HD reception and I'm hoping performance may be better for FM with the HD off. Testing is done on non HD stations or analog FM from an HD station only. The more testing I do the worse it is looking for the GM radio.

 

My 2001 test radio on the 2016 antenna showed poor results. I have to investigate that a little more.

 

I took a 2008 Chevy truck for a ride through my bad signal area and the radio performed well. I would have no complaints with the 2008 truck radio. I also took a 2002 Cavalier through the same area with the same results, excellent radio and good reception. Then I took my 2016 through the same area, nowhere near as good as those two.

Today I rode in a 2014 Ford Explorer. In my opinion after testing on weak stations, it had good FM reception and evidence of automatic bandwidth and tone adjustment to reduce noise. The AM reception on the Ford radio in my opinion was rather poor.

 

Under the latest radio manufacturer guidelines, the radio should adjust bandwidth and tone to minimize the effect of multipath and hiss on FM. I think this is where the older radios were superior. If you did have a weak signal that caused the swishing and static sound, the radio adjusted itself, bandwidth and tone, so it wasn't that objectionable. The 2016 Chevy radio appears to do none of that and allows constant high frequency swishing with multipath and static from weak signals. It had multipath sounding distortion while sitting in a good signal area where three other GM vehicles, 2002 Cavalier, 2008 Chevy truck and 2000 Buick Lesabre, in the same proximity, had no evidence of multipath distortion and sunded clean. Disappointing, and not the Delco quality that I've been used to, and certainly not something you would expect in such a pricey vehicle. I plan to test the sensitivity next if I can.

 

I had a friend hold an aftermarket antenna with a shorter cable adjusted to be the same length as the 2016 Chevy truck antenna out near the end of the passenger side mirror, as far as it would reach. This new antenna measured 70 pF as compared to the 2016 antenna at 170 pF and the performance of the radio appeared to be worse. Seems to point to the 2016 antenna being matched to the 2016 radio.

 

More later.

How do I switch HD Radio on/off on my 2016?

[GeorgeMJ]

To switch the HD on and off: From the "radio" screen, select "menu", and the HD is the 4th selection down. When you tune to an HD station it will display the HD options. If not, turn it off then on and try again.

[GeorgeMJ]

Here is the comparison I promised between several modern car radios. First, the dBf numbers that I used with the post about my 2016 Silverado radio may be in error. Actually I'm a little confused about the dBf or "femtowatts" as it relates to car radios and what usable sensitivity is and how it is measured and at what impedance. Supposedly it takes into account the antenna gain and feedline loss. I made a few assumptions since I'm using commercial equipment with 50 Ohm impedance to measure some radios that may be rated at 75 Ohms and others that may be up to 125 Ohms. So, I used the microvolt reading to get dBm at 50 Ohms, then an on line calculator to get the dBf number from both the microvolts and dBm, (dBm is dB below a milliwatt at 50 Ohms). Since the dBf and dBm are both in power, then each 3dB is a double in power. Again, the 20dB quieting is used as a standard. Some radios would not reach 20dB and are noted as such. u/V means microvolts.

 

Radio u/V for 20dB dBf dBm Comments

2016 Silverado 3 20.79 -97.5 This radio only makes 19dB signal to noise FM quieting, it may get better the longer the signal stays strong?

2001 Silverado 1.5 14.8 -104 For 30dB quieting, 3uV, 20.79dBf, -99dBm

90s Honda 1.4 14.17 -104 For 30dB quieting, 3.2uV, 11.25dBf -97dBm

90s Hyundai 1.2 12.83 -105 For 30dB quieting, 8.0uV, 29.31dBf -88.2dBm

Panasonic DEHD

3900MP 1.3 13.53 -105 For 30dB quieting, 10uV, 31.25dBf, -87dBm Needs local switch to keep from city overload.

GM Theftlock 1.5 14.8 -104 For 30dB quieting, 3.3uV, 21.62dBf, -96.5dBm

 

I also tested a Sony DSXA200ui, and this one performed rather differently than the others. First, the radio mutes the noise if you leave it with no signal. To make it quiet at all, (12dB), it detects a 0.18 uV signal but it doesn't give much audio for this signal. That is -3.65dBf or -122dBm. Very sensitive. It switches to 15dB of quieting with usable audio at 0.29 uV, 0.5dBf, -118dBm. If signal is increased further, the quieting drops to 12dB then increases to 20dB at 9.5 uV or 30.8dBf, -88.5dBm. This radio is by far the most sensitive and does produce usable FM signals far below the signal levels of the other tested radios. It has a published "usable sensitivity" of 7dBf so I don't know what "usable" means. This radio would not receive weak signals well in a strong signal city area, probably overload, but not as bad as older models.

 

I actually installed this receiver in my 2016 Silverado using the "Aux" input of the current system. I also installed an antenna preamplifier or "booster" on the Silverado radio with rather good results. More on that and radio noise performance later.

[jamin87ss]

Say what???? Lol

[GeorgeMJ]

Here is the comparison I promised between several modern car radios. First, the dBf numbers that I used with the post about my 2016 Silverado radio may be in error. Actually I'm a little confused about the dBf or "femtowatts" as it relates to car radios and what usable sensitivity is and how it is measured and at what impedance. Supposedly it takes into account the antenna gain and feedline loss. I made a few assumptions since I'm using commercial equipment with 50 Ohm impedance to measure some radios that may be rated at 75 Ohms and others that may be up to 125 Ohms. So, I used the microvolt reading to get dBm at 50 Ohms, then an on line calculator to get the dBf number from both the microvolts and dBm, (dBm is dB below a milliwatt at 50 Ohms). Since the dBf and dBm are both in power, then each 3dB is a double in power. Again, the 20dB quieting is used as a standard. Some radios would not reach 20dB and are noted as such. u/V means microvolts.

 

Radio u/V for 20dB dBf dBm Comments

2016 Silverado 3 20.79 -97.5 This radio only makes 19dB signal to noise FM quieting, it may get better the longer the signal stays strong?

2001 Silverado 1.5 14.8 -104 For 30dB quieting, 3uV, 20.79dBf, -99dBm

90s Honda 1.4 14.17 -104 For 30dB quieting, 3.2uV, 11.25dBf -97dBm

90s Hyundai 1.2 12.83 -105 For 30dB quieting, 8.0uV, 29.31dBf -88.2dBm

Panasonic DEHD

3900MP 1.3 13.53 -105 For 30dB quieting, 10uV, 31.25dBf, -87dBm Needs local switch to keep from city overload.

GM Theftlock 1.5 14.8 -104 For 30dB quieting, 3.3uV, 21.62dBf, -96.5dBm

 

I also tested a Sony DSXA200ui, and this one performed rather differently than the others. First, the radio mutes the noise if you leave it with no signal. To make it quiet at all, (12dB), it detects a 0.18 uV signal but it doesn't give much audio for this signal. That is -3.65dBf or -122dBm. Very sensitive. It switches to 15dB of quieting with usable audio at 0.29 uV, 0.5dBf, -118dBm. If signal is increased further, the quieting drops to 12dB then increases to 20dB at 9.5 uV or 30.8dBf, -88.5dBm. This radio is by far the most sensitive and does produce usable FM signals far below the signal levels of the other tested radios. It has a published "usable sensitivity" of 7dBf so I don't know what "usable" means. This radio would not receive weak signals well in a strong signal city area, probably overload, but not as bad as older models.

 

I actually installed this receiver in my 2016 Silverado using the "Aux" input of the current system. I also installed an antenna preamplifier or "booster" on the Silverado radio with rather good results. More on that and radio noise performance later.

A copy mistake: The Honda radio for 30dB quieting should be 3.2 uV for 21.35dBf (instead of 11.25 dBf) -97 dBm.

 

Also, my 2016 Silverado radio is at least 6dB worse, (in power), on FM than all of the other radios tested. That is pretty noticeable when compared to another radio connected to the same antenna.

[scott19677]

Here is the comparison I promised between several modern car radios. First, the dBf numbers that I used with the post about my 2016 Silverado radio may be in error. Actually I'm a little confused about the dBf or "femtowatts" as it relates to car radios and what usable sensitivity is and how it is measured and at what impedance. Supposedly it takes into account the antenna gain and feedline loss. I made a few assumptions since I'm using commercial equipment with 50 Ohm impedance to measure some radios that may be rated at 75 Ohms and others that may be up to 125 Ohms. So, I used the microvolt reading to get dBm at 50 Ohms, then an on line calculator to get the dBf number from both the microvolts and dBm, (dBm is dB below a milliwatt at 50 Ohms). Since the dBf and dBm are both in power, then each 3dB is a double in power. Again, the 20dB quieting is used as a standard. Some radios would not reach 20dB and are noted as such. u/V means microvolts.

 

Radio u/V for 20dB dBf dBm Comments

2016 Silverado 3 20.79 -97.5 This radio only makes 19dB signal to noise FM quieting, it may get better the longer the signal stays strong?

2001 Silverado 1.5 14.8 -104 For 30dB quieting, 3uV, 20.79dBf, -99dBm

90s Honda 1.4 14.17 -104 For 30dB quieting, 3.2uV, 11.25dBf -97dBm

90s Hyundai 1.2 12.83 -105 For 30dB quieting, 8.0uV, 29.31dBf -88.2dBm

Panasonic DEHD

3900MP 1.3 13.53 -105 For 30dB quieting, 10uV, 31.25dBf, -87dBm Needs local switch to keep from city overload.

GM Theftlock 1.5 14.8 -104 For 30dB quieting, 3.3uV, 21.62dBf, -96.5dBm

 

I also tested a Sony DSXA200ui, and this one performed rather differently than the others. First, the radio mutes the noise if you leave it with no signal. To make it quiet at all, (12dB), it detects a 0.18 uV signal but it doesn't give much audio for this signal. That is -3.65dBf or -122dBm. Very sensitive. It switches to 15dB of quieting with usable audio at 0.29 uV, 0.5dBf, -118dBm. If signal is increased further, the quieting drops to 12dB then increases to 20dB at 9.5 uV or 30.8dBf, -88.5dBm. This radio is by far the most sensitive and does produce usable FM signals far below the signal levels of the other tested radios. It has a published "usable sensitivity" of 7dBf so I don't know what "usable" means. This radio would not receive weak signals well in a strong signal city area, probably overload, but not as bad as older models.

 

I actually installed this receiver in my 2016 Silverado using the "Aux" input of the current system. I also installed an antenna preamplifier or "booster" on the Silverado radio with rather good results. More on that and radio noise performance later.

 

 

Can you help me with my VCR that won't stop blinking 12:00?

[GeorgeMJ]

Well, I've spent just about all the time I'm going to on this for now. My 2016 Silverado radio is pretty bad as compared to other modern car radios and turning the HD on or off doesn't make any difference in receiving weaker stations at all.

 

This radio can be helped by an FM Antenna Booster like I used back in the 70s to help the junky FM aftermarket radio in my 63 Chevy. The type I used is switchable since it does not work on AM. Do a search on the web or ebay for an "ab150 booster".

There are many types of these as well but the two I bought did not work as received. A bad solder joint bridging two pads that aren't supposed to be connected caused a resistor to burn up. If you're interested, email me for a picture of the errant solder. This happened on both that I bought on Ebay from two different sellers, both slightly different than the one on Amazon. This amplifier offers 10 to 12 dB of gain on FM and makes the radio usable again, even on HD. If you are interested, email me for the picture or for the information on the adapters that you will need to connect this thing. The adapters put the switch right below the dash front cover and make the switch easy to use.

 

I'm experimenting with another type of booster that looks like a small plastic box with two cables and a power wire coming out of it. Presently it is too strong and overloads the radio. There are others available, some don't even have an amplifier in them, just put power on the feed line. Lots of junk out there! The booster does make the radio close to other modern car radios and it may be all that you need. Really a shame that you have to install junk like this to make the radio in your $50k vehicle work almost as well as a Hyundai Accent radio.

 

So, being as picky as I am, I decided to install an aftermarket radio under the dash of my truck. I used the Sony from the earlier tests and I ran the preamp outputs into the Aux input of the Mylink radio, (located in the center arm rest of mine). I modified the Sony to disconnect power to the output amplifier so it will use less power in case I forget to turn it off and it stays cool like this as well. I used an extra antenna booster switch, rewired, to select the Sony radio, keeping the function of the original radio for use with the booster or for AM reception, (Sony is a little better there too). That's the way I'm running it for now, really tough to look at that and realize you have to do this to a high priced vehicle just to have a decent radio. I selected the Sony radio because of its good advertised performance and it has a remote control so I don't have to reach the radio to operate it.

 

Now, there are other ways to do this and not bother the Mylink, keeping all steering wheel and sound functions without adding all sorts of adapter junk and cutting up the dash. You can forget about the antenna booster and switch and just install a new radio and two hidden speakers somewhere like under the seats, connect the antenna and there you go! You can also buy an adapter to bluetooth and connect your aftermarket radio to the system that way, or you can use an FM transmitter and go in that way. You might even experiment with some sort of antenna splitter to have both usable without a switch but I would recommend a booster before that to help with signal loss.

 

Ron mentioned above that he owned both 2014 and 2016 Silverados and the 2016 has an improved radio. I may have one like Ron's, but I also may have a bad one, tough to tell without GM telling you if you have a "bad" radio or just a "normally bad" radio. I hope to hear from more folks with similar results. Also if some of you with 2014s and 2015s can go to the dealer and test drive a 2016 maybe we can learn from that as well.

 

I haven't had my truck in for an oil change or any service yet and I will mention the poor FM radio performance when I do. If anything changes or if I find out anything about the radios I will post it. I did receive an invite to have an upgrade for some sort of Android app for the Mylink installed and I probably will do that with hope that there may be an FM radio update included. I think you can email members so email me if you need more information on anything I wrote about or post it here.

 

My training and job and hobby allow me to experiment like this and it was fun, but I don't think the outcomes are anything to smile about!

[pappas pit]

how and where do you install the FM Antenna Booster ? and thank you very much for your efforts and info

[GeorgeMJ]

OK, here's how I did it. Please realize that I am not telling you to do anything or how to do anything, just how I did it. Anything you do is at your own risk, please don't try this at home!

 

First, I familiarized myself with what the antenna wire looks like, I saw enough of it by opening the hood and looking at it near where the antenna enters the firewall. Then I made sure I had a good booster, one that doesn't make smoke or smell funny when I applied power. The LED will light even though the bad connection is present. It uses a separate resistor from the power supply. The resistor burned on the first applicaton of power. It measured 100 Ohms and matched the markings so it wasn't bad. I bought two adapters a Metra 40-EU20 and a Metra 40-EU10 or equivalents. I went to youtube and searched for 2015 Silverado radio removal, there is none for 2016 and this one is the same, here if the link works:

I don't know if I can post a picture here but I will try to of the bad solder connection. Again, email me and I'll send it to you.

 

I didn't remove any plugs and just laid back the trim and display panel. I found the antenna wire and connector, it comes to the radio module from the right facing the dash, I believe the connector was green or black. I had to squeeze the connector to disconnect it. I installed the adapter to the removed cable and ran it straight down right side of the trim, (facing the dash), behind the trim panel, where there is a path to get behind the dash trim and down to the center hump. I used a bright flashlight to find it. The adapter made the cable long enough and if I needed more, there was a wire tie to cut just to the right of the radio module, This wire with adapter now plugged in to my booster, the socket in the booster. I used a piece of solid wire to fish through the path to find it.

 

I then plugged the other adapter in to the radio where I removed the antenna cable. I ran the output wire from the booster up the same way that the antenna wire and adapter went down to the hump. Again, the output of the booster, the cable, is now connected to my radio. The input of my booster, the socket, is connected to the antenna. I connected the red or positive wire to a battery connection at the fuse panel, through a fuse holder and 1 Amp fuse right at the panel. I used the 12 Volts available on one of the 30Amp spare fuses. For initial testing, I connected the red wire to a fused cigar lighter adapter, it can be left this way. My booster gets its ground connection from the antenna cable. I don't know where the "Retained Accessory Power" or just accessory power is available.

[glcbn]

Thank you very much for this info. It would have been nice to see the booster addition put to video too. I'm one that likes to "see" procedures before I attempt them. Great info nonetheless.