Replacing antenna booster - SOLVED
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Racer
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From: Ponte Vedra Beach, FL (Jacksonville)
Replacing antenna booster - SOLVED
Hi Everyone,
I am about to receive the new Nakamichi CD Reciever/Changer for my 1988 928 S4 and I plan on replacing the antenna booster as part of the upgrade.
1) Does someone have a description and photos of how to remove the glove box on the car?
I looked at the manuals and there was nothing specific about removing the glove box to get in behind it. My understanding from searching the forums that the existing antenna booster is behind the glovebox.
2) Does anyone have a photo showing the antenna booster in place - that would be a big help to see how it mounted and connected.
I found two antenna boosters online, photo attached, at a total cost of less than $30 so I bought them both.
You never know, but I am sure they are more up to date that a replacement booster and a whole lot cheaper. One of them is going to end up in the car.
I am leaning towards the little silver one, as the company selling it claims it boosts both AM and FM bands and is used as a replacement in Mercedes and other EU manufactured cars.
Thanks in advance for your help.
VTY,
Joe
I am about to receive the new Nakamichi CD Reciever/Changer for my 1988 928 S4 and I plan on replacing the antenna booster as part of the upgrade.
1) Does someone have a description and photos of how to remove the glove box on the car?
I looked at the manuals and there was nothing specific about removing the glove box to get in behind it. My understanding from searching the forums that the existing antenna booster is behind the glovebox.
2) Does anyone have a photo showing the antenna booster in place - that would be a big help to see how it mounted and connected.
I found two antenna boosters online, photo attached, at a total cost of less than $30 so I bought them both.
You never know, but I am sure they are more up to date that a replacement booster and a whole lot cheaper. One of them is going to end up in the car.
I am leaning towards the little silver one, as the company selling it claims it boosts both AM and FM bands and is used as a replacement in Mercedes and other EU manufactured cars.
Thanks in advance for your help.
VTY,
Joe
Last edited by JoeTaylor; Jan 28, 2010 at 01:46 PM.
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From: Philly PA
glove box removal is easy .
it is also a good idea to remove the lower parcel tray first .
look for a 2 wire harness that has a 2 pin connector, this is for the glove box light disconnect it , it is just over the computers, ( so you dont damage the wires when you pull out the glovebox).
Then remove the screws in the top side inside the box including the latch, then remove the screws along the underside of the door, the door drops off then carefully pull the hose off the right side inner box this is a AC feed to keep the G box cool. then pull out the inner box pay attention to the light wires.
The antenna amp is behind this against the firewall.
That said i would test this first before i went out and bought another one, as its made for your car
it is also a good idea to remove the lower parcel tray first .
look for a 2 wire harness that has a 2 pin connector, this is for the glove box light disconnect it , it is just over the computers, ( so you dont damage the wires when you pull out the glovebox).
Then remove the screws in the top side inside the box including the latch, then remove the screws along the underside of the door, the door drops off then carefully pull the hose off the right side inner box this is a AC feed to keep the G box cool. then pull out the inner box pay attention to the light wires.
The antenna amp is behind this against the firewall.
That said i would test this first before i went out and bought another one, as its made for your car
Chronic Tool Dropper
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OK---
In the probably 15 or more years since the booster was made for you car, there have been giant leaps in he technology of low-noise small-signal antenna amps. Almost anything will be a lot better than what's in the car from the factory. Ditto on the actual radio receivers made today. Cheapest today better than the best of 15 years ago. Make sure your leads are well dressed, short ground leads and signal wire to the head unit, and you should be fine.
K's 4Runner has a real diversity antenna system in the rear quarter windows, and the plain-jane radio in that car kicks my Blau Alaska (now 8 years old) with the factory roof antenna and amp when it comes to signal quality and image rejection. I can easily see the local transmitter site on Mt. Wilson maybe a dozen miles away as the crow flies, and signals are so strong her that there's serious multipath overload. Toyota radio is great, mine is the pits until I get a ways away from the mountain.
In the probably 15 or more years since the booster was made for you car, there have been giant leaps in he technology of low-noise small-signal antenna amps. Almost anything will be a lot better than what's in the car from the factory. Ditto on the actual radio receivers made today. Cheapest today better than the best of 15 years ago. Make sure your leads are well dressed, short ground leads and signal wire to the head unit, and you should be fine.
K's 4Runner has a real diversity antenna system in the rear quarter windows, and the plain-jane radio in that car kicks my Blau Alaska (now 8 years old) with the factory roof antenna and amp when it comes to signal quality and image rejection. I can easily see the local transmitter site on Mt. Wilson maybe a dozen miles away as the crow flies, and signals are so strong her that there's serious multipath overload. Toyota radio is great, mine is the pits until I get a ways away from the mountain.
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Racer
Joined: Jun 2009
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From: Ponte Vedra Beach, FL (Jacksonville)
Hi Merlin and Bob,
Smiles, no worries about image rejection, I am a "flat lander" living here in Florida. Not much for a signal to reflect off here.
I am BSEE '82, all audio/radio gear is hundred times better than that designed back in the day I was in university.
I suspect the antenna booster is either weak or not working on my car, so the plan it to try both of the antenna amplifiers (boosters) and see which one works the best. My belief is even the worst design today is better than something designed back in the late '70's, early '80's.
I am more concerned about 1) getting in and out of the glovebox removal without messing it up and 2) being able to remove and replace the old booster. All the while, doing a neat job of it. Thats why I wanted some photos and instructions to see what I was getting myself into.
If I need antenna cable extension(s) or other mounting/installation stuff, I thinks its better to gather it up in advance, so I have everything on hand when I get started. Thus the need for help.
VTY,
Joe
Smiles, no worries about image rejection, I am a "flat lander" living here in Florida. Not much for a signal to reflect off here.
I am BSEE '82, all audio/radio gear is hundred times better than that designed back in the day I was in university.
I suspect the antenna booster is either weak or not working on my car, so the plan it to try both of the antenna amplifiers (boosters) and see which one works the best. My belief is even the worst design today is better than something designed back in the late '70's, early '80's.
I am more concerned about 1) getting in and out of the glovebox removal without messing it up and 2) being able to remove and replace the old booster. All the while, doing a neat job of it. Thats why I wanted some photos and instructions to see what I was getting myself into.
If I need antenna cable extension(s) or other mounting/installation stuff, I thinks its better to gather it up in advance, so I have everything on hand when I get started. Thus the need for help.
VTY,
Joe
Thread Starter
Racer
Joined: Jun 2009
Posts: 496
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From: Ponte Vedra Beach, FL (Jacksonville)
Hi Tom,
I found the silver antenna booster on Ebay for $7, here is the link:
http://cgi.ebay.com/Car-Antenna-Radi...item5ad6a4b6f2
Here is the link for the other antenna booster, just in case:
http://www.hifisoundconnection.com/S...id/0/SFV/30046
I bought both because they were so cheap. Going to try them to see which one works the best. Good luck on yours.
VTY,
Joe
I found the silver antenna booster on Ebay for $7, here is the link:
http://cgi.ebay.com/Car-Antenna-Radi...item5ad6a4b6f2
Here is the link for the other antenna booster, just in case:
http://www.hifisoundconnection.com/S...id/0/SFV/30046
I bought both because they were so cheap. Going to try them to see which one works the best. Good luck on yours.
VTY,
Joe
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From: Mansfield, TX
With the improvements in the radio receivers are the boosters still even needed?
Maybe put the Nak in first and see if you even need it, save all the trouble.
When I put my MB-VI in earlier this month I didn't wire up the factory booster and I'm getting the local FM stations just fine with the in glass antenna.
Maybe put the Nak in first and see if you even need it, save all the trouble.
When I put my MB-VI in earlier this month I didn't wire up the factory booster and I'm getting the local FM stations just fine with the in glass antenna.
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Chronic Tool Dropper
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Jay, did you bypass the factory amp or just leave the amp power lead disconnected? There's a significant difference on most amps. Leaving it unpowered but not bypassed may actually hurt the signal levels compared to a wire that just goes direct from antenna to radio.
For those in the know, where is the amp on later ('89+) cars located? These are the cars with the rooftop antenna. If the amp is still forward of the glovebox, mine will be replaced very soon. If it's part of the antenna base as I suspect, not so soon...
For those in the know, where is the amp on later ('89+) cars located? These are the cars with the rooftop antenna. If the amp is still forward of the glovebox, mine will be replaced very soon. If it's part of the antenna base as I suspect, not so soon...
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Verdad Gallardo
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From: Royse City, TX
There is a write up on removing the whole dash. It has a few pictures with the removing glove box part. It is not real detailed on the glove box, but does show you some. The Glove box removal start around step 27. Step 28 talks about removing a bolt that holds the dash in, you will not want to remove it just to get the box out.
When I removed my glove box to work on my AC in the '89, I did not disconnect the bttry ground. That was a mistake. I blew the fuse for the interior lights.
http://www.landsharkoz.com/forms/928_dash_removal.pdf
When I removed my glove box to work on my AC in the '89, I did not disconnect the bttry ground. That was a mistake. I blew the fuse for the interior lights.
http://www.landsharkoz.com/forms/928_dash_removal.pdf
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From: Mansfield, TX
Jay, did you bypass the factory amp or just leave the amp power lead disconnected? There's a significant difference on most amps. Leaving it unpowered but not bypassed may actually hurt the signal levels compared to a wire that just goes direct from antenna to radio.
The car is down waiting on some parts but when it's running again I'm gonna drive around and see how the signal is in different parts of town. If I get fading I'll bypass the antenna amp then but at least sitting in my garage it's getting a good strong signal from all the local stations with no power to the amp.
Modern receiver sensitivity is such that I'm just not sure we need to be worrying about the antenna amp any more.
When I removed my glove box to work on my AC in the '89, I did not disconnect the bttry ground. That was a mistake. I blew the fuse for the interior lights.
Drifting
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From: Stratford-upon-Avon
My amp was no longer working and the radio reception was terrible, so I replaced the whole thing with a Golf/Rabbit antenna. Excellent radio reception now.
The power lead for the antenna amp travels with the RF co-ax up till a few inches from the base, then it's split away and has a separate connector to flying lead from the roof.
The photo shows the old amp after I'd broken apart the base. The potting compound (usually clear) had transformed into this papery/foam-like substance!
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The amp is integral with the bee-sting antenna, and located in the antenna base (antenna screws onto this part).
My amp was no longer working and the radio reception was terrible, so I replaced the whole thing with a Golf/Rabbit antenna. Excellent radio reception now.
The power lead for the antenna amp travels with the RF co-ax up till a few inches from the base, then it's split away and has a separate connector to flying lead from the roof.
The photo shows the old amp after I'd broken apart the base. The potting compound (usually clear) had transformed into this papery/foam-like substance!
My amp was no longer working and the radio reception was terrible, so I replaced the whole thing with a Golf/Rabbit antenna. Excellent radio reception now.
The power lead for the antenna amp travels with the RF co-ax up till a few inches from the base, then it's split away and has a separate connector to flying lead from the roof.
The photo shows the old amp after I'd broken apart the base. The potting compound (usually clear) had transformed into this papery/foam-like substance!
I'm in the same situation and guess I will need to replace the antenna, as all other remedies have failed to improve my radio reception.
Is there w arite-up out there for replacing the roof-mout antenna? My understanding is this job is a bitch due to the sunroof motor assembly interfering with easy access.
Thanks.
Drifting
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From: Stratford-upon-Avon
Hi Randy,
I bought the antenna from a UK supplier (GSF = German, Swedish & French) where it was described as Roof Aerial (Amplifier) for Golf Mk II. There were a few Golf antennas in their catalogue so I went along and selected the most likely-looking with same thread from a bunch they brought out of stores. It cost about $30 so a lot cheaper than the Porsche part!
Fact that I managed it shows job isn't that hard! Easy to drop the sunroof motor (a few nuts to remove the gear reducer thing and two rubber mounts for the reducer, I don't think you even need to remove motor but I did as I had a used replacement which ran a little smoother).
The only tricky thing is getting at the nut where the original antenna is attached to roof. Conventional wrench won't go into recess so I used what we call a box spanner here (pictured). It's 17 or 19mm. You gently move the solid sunroof cable guides out of way to create space for the wrench (they are pretty flexible).
The Porsche antenna has a square flange to hold it in square hole in roof so needn't be counterheld as you loosen/tighten. The replacement had no flange but the rubber base seems to fit pretty tightly over hole, and no water has come in that way with rain or washing car. You need assistant to hold it as you tighten from inside car or you're ok if you have long arms!
The other photo shows at on right the connections for the co-ax antenna and the antenna amp, just to left of foam protection.
The replacement antenna had a different plug from original. I just got an adapter at auto parts store which plugged straight into existing cable going to radio.
Oh the amp power lead had a different connector on replacement. I just crimped on connector from original - dead simple.
I bought the antenna from a UK supplier (GSF = German, Swedish & French) where it was described as Roof Aerial (Amplifier) for Golf Mk II. There were a few Golf antennas in their catalogue so I went along and selected the most likely-looking with same thread from a bunch they brought out of stores. It cost about $30 so a lot cheaper than the Porsche part!
Fact that I managed it shows job isn't that hard! Easy to drop the sunroof motor (a few nuts to remove the gear reducer thing and two rubber mounts for the reducer, I don't think you even need to remove motor but I did as I had a used replacement which ran a little smoother).
The only tricky thing is getting at the nut where the original antenna is attached to roof. Conventional wrench won't go into recess so I used what we call a box spanner here (pictured). It's 17 or 19mm. You gently move the solid sunroof cable guides out of way to create space for the wrench (they are pretty flexible).
The Porsche antenna has a square flange to hold it in square hole in roof so needn't be counterheld as you loosen/tighten. The replacement had no flange but the rubber base seems to fit pretty tightly over hole, and no water has come in that way with rain or washing car. You need assistant to hold it as you tighten from inside car or you're ok if you have long arms!
The other photo shows at on right the connections for the co-ax antenna and the antenna amp, just to left of foam protection.
The replacement antenna had a different plug from original. I just got an adapter at auto parts store which plugged straight into existing cable going to radio.
Oh the amp power lead had a different connector on replacement. I just crimped on connector from original - dead simple.
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From: Philly PA
to replace your roof antenna remove the sunroof motor cover remove the screws that anchor the track rods if the tracks are in the way.
Disconnect the wires, one unplugs and the coax is a screw on coupler, then with a good set of long needle nose pliers grip the securing nut for the antenna base,
A helper is a good thing here to hold the antenna while the nut is removed.
Install is the reverse of take apart
Disconnect the wires, one unplugs and the coax is a screw on coupler, then with a good set of long needle nose pliers grip the securing nut for the antenna base,
A helper is a good thing here to hold the antenna while the nut is removed.
Install is the reverse of take apart
