I was working on my 88 GT the other day and the ugliness of the antenna started getting on my nerves. Its time that it moves itself underneath the fender. Im almost done with the relocation, but I need some help finding out some information about the stock antenna system.
To be able to get to the frame underneath the quarter panel without taking the entire quarter panel off, you have to remove the antenna from the Antenna Base that mounts onto the frame. I removed the original antenna with a wrench, but sheared the bolt on the Antenna Base. This sounds like its a very common problem. I bought a new antenna that uses an M6-1.0mm thread - Is this the same as the original antenna?
On the Fiero Store, i could buy a new antenna base for $30, make a bracket to hold the antenna base sideways and mount my new antenna on the antenna base. I dont like this idea because the only location with enough space is so low on the car, you would most likely have remove the quarter panel and wheel well cover. I felt like i could come up with a better design with a better location that requires less work for cheaper. http://www.fierostore.com/P...Detail.aspx?s=61602U https://www.fiero.nl/forum/A...040710-2-048858.html
After deciding to not use the stock antenna base, i ran into the problem of connecting the existing coax antenna cable to my new antenna mount. I went to my local car audio store to see if they had any connectors to would fit the coax cable, but i wasnt able to find anything that would work. It seems that this magical unicorn connection between the coax antenna cable and the antenna base does not use standard connectors. Finally, I was able to make my own connector by cutting up two standard coax cable connectors that can be found at a car audio store and combining them. Does anyone know if there is any premade connectors that fits the coax cable that plugs into the antenna base?
Also, if a man was to remove the antenna, but leave the antenna base installed on the car, does the bolt on the antenna base stick out of the body work? Since that bolt sheared off, im not able to tell.
Relocating this antenna has been such an ordeal with breaking parts and finding the right connectors, im wondering if there is a kit that already exists or if a kit needs to be made. Ill post some pictures showing where i plan on relocating the antenna and the special connector that i made. I hear that an antenna mounted on both sides of the car gives the best reception. I may do this in the future as well, which would require an additional custom wiring harness.
================================================== Question 1: What is the thread of the bolt that protrudes out of the antenna block mounted on the frame that the antenna screws on to?
Question 2: Is there a premade connector that fits the coax cable that plugs into the antenna base?
Question 3: Does the bolt on the antenna base stick above the body work when the stock antenna is removed? ==================================================
At a show a few years ago I spoke with a Fiero owner who used the defroster trace on the rear window as his radio antenna.....he said it worked perfectly.
At a show a few years ago I spoke with a Fiero owner who used the defroster trace on the rear window as his radio antenna.....he said it worked perfectly.
That's an interesting idea. Does the ground side of the coaxial antenna cable need to be grounded near the window?
This may be of help. There is also a hidden antenna on ebay. I used one in a previous Fiero.
I don't have answers to your questions.
Tshark, thanks for the link! I saw that as i was doing some research. Thats a really slick way of hiding the antenna. Unfortunately, im too lazy to do that work... Thats an awesome job they did.
Ill try to figure out why the photos didnt post correctly... If you click on the error messages, it will take you to the photos in PhotoBucket. Also, i should have this project finished by tomorrow and i will show my mounting bracket and antenna placement.
Ill try to figure out why the photos didnt post correctly... If you click on the error messages, it will take you to the photos in PhotoBucket.
The preferred method of posting images here is PIP... and the images will never disappear from the posts/threads.
I didn't hide my antenna, but I started out with the same problem as you (as discussed in this thread - Antenna replacement). Might be something in there that could be helpful to you.
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Originally posted by Alibi:
You don't have to remove the cable (from the car), it just plugs into the base. It is stubborn so spray it with some penetrant first and then twist it off, don't yank or else you might pull the end apart.
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Originally posted by Patrick:
I picked up a Formula last year that had the stud broken off the antenna base. With everything else I've been doing with this car, fixing this issue was low on my list of priorities... so I've suffered for the last year with very limited radio reception (no antenna).
I finally decided to fix this, and I was very happy to read the above post and realize that the coax cable did NOT need to be removed from inside the car.
Sure enough, the coax cable just sort of twisted/pulled off the base. Did the opposite to attach it to a good base from one of my parts cars. I've got a zillion radio stations to listen to now!
I love this forum. Special thanks to Alibi for the info quoted above.
Thanks Patrick, ill try to correct my images using PIP sometime in the next day.
Thankfully i tried to pull the coax cable out of the antenna base before i decided just to cut the coax cable at the antenna base. You are right, you dont have to pull the entire cable through the frame right in front of the door.
I just need to pick up a few parts to finish the relocation. Im very pleased that all you really need to do is loosen the quarter panel enough to pull it away from the frame to be able to have enough access to mount the antenna. Ive seen way to many forums were they have taken the entire quarter panel and wheel well cover off.
I reserved the first post so that i can go back and post a tutorial along with a wiring diagram, etc.
I don't know if this was mentioned elsewhere, but you should put a piece of plastic tubing over the antenna. If the metal mast touches the spaceframe it will likely kill the signal. Also, having the antenna in close proximity to the spaceframe will tend to shadow the signal, and make the antenna very directional. (Sounds like you already know that.)
I don't know if this was mentioned elsewhere, but you should put a piece of plastic tubing over the antenna. If the metal mast touches the spaceframe it will likely kill the signal. Also, having the antenna in close proximity to the spaceframe will tend to shadow the signal, and make the antenna very directional. (Sounds like you already know that.)
Yeah, Great point. I cant remember where i read it, but somebody put an antenna on both sides of the car and said that that gave them the best reception (better than the stock antenna location). I have to assume that he put an antenna on both sides because of what you mentioned. Im sure the spaceframe blocks a lot of signals from the other side of the car.
During my commute to work, i go in and out of range of a few radio stations. I know where the signal normally ends. When i get the car back to together, im curious to see how much the antenna relocation hurts my reception.
Fender is low plus frame is ground plane and hides the antenna from getting good signal, especially at medium to long distances.
I just put a wire along the edge of windshield and connected to antenna base. Hides the antenna w/o killing signal. Did that because kids break off antennas.
Two antennas can cause signal problems and often not a simple as splicing two antennas to a wire. You should read real antenna data, not BS posted on many forums.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
I think ( theogre ) is onto something with just attaching a wire to the Antenna Base stud . It would give you more flexibility in your mounting, and you might be able to bring the wire up the A-Pillar by carefully tucking it between the drip rail and chassis as an option. The length of the wire is important for good radio reception,( advised to me by people who know alot more about radios than me ) so I would start with a wire that is 32" long ( same as the original antenna mast) and go from there.
In your original question you asked about ...... * the antennae base stud size?....measured this mourning, its metric ( M6 x 1.0 ) ~ 8mm in length. * and does it come through the fender? .... No, it sits below by about (3/16" to 1/4")
Originally posted by Orig88GT-NC: I think ( theogre ) is onto something with just attaching a wire to the Antenna Base stud . It would give you more flexibility in your mounting, and you might be able to bring the wire up the A-Pillar by carefully tucking it between the drip rail and chassis as an option. The length of the wire is important for good radio reception,( advised to me by people who know alot more about radios than me ) so I would start with a wire that is 32" long ( same as the original antenna mast) and go from there.
OE radio uses AM and FM and means different bands. (AM 530-1610KHz, FM 87-108MHz.) will get different tuning on a band but really is not a big problem for receiving. A poor tune of antenna is more of a problem in rural areas because that will kill channels. Is a big issues using any 2-way radio. Miss-match eats power in transmission and can ever kill the radio's output transistors.
Perfect match to a channel can vary a lot... long story, google: 1/4 wave antenna length Good calculator is http://www.csgnetwork.com/freqwavelengthcalc.html Examples: 1/4 wave antenna for X channel = Y 108MHz = 27.33 Inches (high FM) 100MHz = 29.52 Inches (middle FM) 88MHZ = 33.55 Inches (low FM) 1000KHz = 2952 Inches/246 Feet (middle AM) Just for fun... 27MHZ = 108 Inches/9 feet for CB radio band. Is why "whip" antennas are 9 feet. All Shorter uses load coils. WiFi 2.4GHZ band = 1.23 Inches for 1/4 wave, 4.95 full wave
Your 32 inches means is tuned for FM band but a few inches off won't matter much. AM can use same antenna especially because you aren't transmitting.
Bigger issue is the antenna hidden in the fender. Car's body is the ground plane for all antennas attach to it. You don't want your antenna buried in the car's metal to get a good signal. (google: antenna ground plane) Have antenna close to A pillar isn't the best but likely better then under fender. I get most channels using a wire under glass trim even driving in rural areas.
Ogre's idea about using a wire inside the windshield trim sounds like a good idea. In reality, you could probably run a wire underneath any body panel and receive a decent signal, provided that you weren't using metallic paint. The metal flakes in the paint might tend to block the signal. Ideally, you would want to keep the wire as far as possible from the metal structure of the car, as he mentioned.
My dad used to experiment with antenna design for some two-way equipment that we had. He got the best results from some of the damnedest things. Play around. Figure out what works.
I realized, when I bought my G6, that the radio antenna looks like part of the rear window defroster grid, except that it's at the top of the window, and separated from the real defroster by a couple of inches.
In the 60s, GM used wires embedded in the windshield glass for radio antennas. They sort of worked. I'll bet they would have worked better for FM, had it been in common usage at the time.
[This message has been edited by Raydar (edited 01-12-2015).]
Originally posted by Raydar: In the 60s, GM used wires embedded in the windshield glass for radio antennas. They sort of worked. I'll bet they would have worked better for FM, had it been in common usage at the time.
Early 70s... Family had a GM car w/ this. Other markers still use this plan. Two fine wires you could see. They work good in most places.
is hard to see because tint... start at bottom then bends 90° about 2-3 inches at top
Awesome information Ogre! Great job educating about wavelength.
Real Fast, i fixed my pictures in the first few posts, thanks Patrick
I wouldnt be happy with myself until i found out how much signal i lost with the antenna being placed under the fender vs the stock antenna location vs a wire on the dash.
When i was in college, we used to use these extremely expensive devices called Spectrum analyzers. They are used to probe RF electronics and display the amplitude of signals at various frequencies. For example, if you make a 1Mhz sine wave generator, you will always have harmonics that appear in the signal (2 Mhz, 3 Mhz, 4Mhz etc.) The harmonics will always be less than the primary signal, but can cause problems in some circuits. Normally, spectrum analyzers cost a minimum of $2,000 - $4,000 for a decent one.
Picture of a Spectrum Analyzer:
I found an incredible device for $20 that allows me to do exactly what a spectrum analyzer does between the frequencies of 22Mhz to 1.7Ghz. It was originally designed to be a TV tuner that allowed you to watch analog TV channels on your computer. It didnt take long before some geniuses realized that the device could do much more than watch TV. With a small change to the driver on your computer, it allowed the users to adjust the frequency that the device filtered into. It also allows the device to sweep through every frequency and display the amplitude of the signal at all of the frequencies like a spectrum analyzer. Here is their homepage: http://www.rtl-sdr.com/about-rtl-sdr/
I plan on plugging in the antenna to this device and using an FM transmitter to measure the signal strength at various angles of the fiero with the antenna in various orientations. Ogre is right, there is a lot of BS out there, hopefully having real data will debunk some of this. Who knows, we may be surprised with the results.
I found an incredible device for $20 that allows me to do exactly what a spectrum analyzer does between the frequencies of 22Mhz to 1.7Ghz. It was originally designed to be a TV tuner that allowed you to watch analog TV channels on your computer. It didnt take long before some geniuses realized that the device could do much more than watch TV. With a small change to the driver on your computer, it allowed the users to adjust the frequency that the device filtered into. It also allows the device to sweep through every frequency and display the amplitude of the signal at all of the frequencies like a spectrum analyzer. Here is their homepage: http://www.rtl-sdr.com/about-rtl-sdr/
Interesting stuff. If you feel so inclined, you might like to start a thread in O/T to discuss this further. A few of the guys who hang out there might enjoy hearing what you can do with this inexpensive technology.
Its time that it moves itself underneath the fender.
From my experience, this was a bad idea. You're putting the antennae behind metal which shields radio reception. I tried it while i was in Los Angeles (many strong stations/signals) and noticed a definite loss of reception. My preference was to move the antenna to the rear quarter where it looked better (to me). You can also get a Dakota Digital electronic antenna and hide it in the roof under the headliner - worked well in my other car. Dakota Digital stuff is over-priced but works.
Originally posted by Raydar: In the 60s, GM used wires embedded in the windshield glass for radio antennas. They sort of worked. I'll bet they would have worked better for FM, had it been in common usage at the time.
The '60's??? Porsche was still using it on their 2007 911's. Reception was certainly not as good as an external antenna.
I'm quite familiar with them. Not something that average persons (or even a lot of 2 way radio shops) have on hand. Obviously you have some background.
THANK YOU for sharing the info about the receiver. That's pure gold. Not that I have a lot of need for a spectrum analyzer these days, but it's nice to know that it's out there. Good show!
I'm curious what you do for a living or hobbies. Sounds like you've had more than a basic introduction to RF.
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Originally posted by Patrick:
I remember that as well, but I think it was bit later... maybe the 70's. Anyway, it was back when we were young and fearless.
I was thinking that my dad's '68 Bel Air had a windshield antenna. Came out about the same time as hide-a-way wipers. We were impressed with how well it didn't work. (Remember... This was on the AM band, back then.) I was curious... Craigslist shows a few '68s with no antenna on the fender, so I have to believe that I'm remembering correctly. Anyway...
I'll bet they would have worked better for FM, had it been in common usage at the time.
