Blue90 Posted January 29, 2013 Share Posted January 29, 2013 When I started my car this morning the antenna went up, even though the power to the radio was off. Everything else works normally. The antenna goes down when I shut the car off and open the door; not when I turn the power button off. What happened? Link to comment Share on other sites More sharing options...
Guest steveskyhawk Posted January 29, 2013 Share Posted January 29, 2013 Radio is on with volume turned down Link to comment Share on other sites More sharing options...
Blue90 Posted January 30, 2013 Author Share Posted January 30, 2013 I just went out and checked again. The radio is off. Link to comment Share on other sites More sharing options...
Guest Mc_Reatta Posted January 30, 2013 Share Posted January 30, 2013 Sounds like the circuit in the radio that sends the signal to the antenna has shorted out. If that's the case, radio will need to be repaired or replaced. Another option is to install a switch on the line and control the antenna manually. Link to comment Share on other sites More sharing options...
Guest Corvanti Posted January 30, 2013 Share Posted January 30, 2013 remove the negative battery cable for a few minutes, then reconnect. if that doesn't do it, pull the electrical connections to the antenna starting in the trunk and go forward and clean them with "CRC QD Electrical Cleaner". check the electrical grounds pertaining to the system.if any of those doesn't fix the problem, then think about pulling the radio, etc. out. Link to comment Share on other sites More sharing options...
Barney Eaton Posted January 30, 2013 Share Posted January 30, 2013 You can isolate the problem by......pull the connector coming from the front of the car at the antenna relay. Wire #4 (orange) on the attached picture should have 12v all the time. wire #6 (pink) should have 12v when the radio is on.If the above checks out, replace the antenna relay (I have plenty) If #6 does not have 12v with the radio on then there is probably a problem inside the radio. Link to comment Share on other sites More sharing options...
Blue90 Posted January 31, 2013 Author Share Posted January 31, 2013 Removing the negative battery cable for a couple of minutes did it. Thanks everyone for your responses. Link to comment Share on other sites More sharing options...
Guest Corvanti Posted January 31, 2013 Share Posted January 31, 2013 i love it when one of my "easy" fixes work!!!:cool: Link to comment Share on other sites More sharing options...
DAVES89 Posted January 31, 2013 Share Posted January 31, 2013 So Barney if I go out to the local U Pick how would I check an antenna w/o a key. I would need it to go up and of course go back down. I would have a 12 volt power station with me. Link to comment Share on other sites More sharing options...
Barney Eaton Posted January 31, 2013 Share Posted January 31, 2013 (edited) The schematic shows you.......... ground 5, 12v to 6 and it will go up switch 12v to 4 and it goes down.If the motor runs but it does not go up or down the plastic line is broken.I rebuild them with a steel cable for $50If you find any pre-1980 antenna with good mast I can use them. They look like they have a soup can at the bottom......see picture. Edited January 31, 2013 by Barney Eaton (see edit history) Link to comment Share on other sites More sharing options...
Blue90 Posted January 31, 2013 Author Share Posted January 31, 2013 Barney, What pre-1980 cars have the mast you need? Link to comment Share on other sites More sharing options...
Barney Eaton Posted January 31, 2013 Share Posted January 31, 2013 Any GM car with a power antenna. (1960-1979) They were made by Tenna but there is no name on the antenna. The picture I posted is the "automatic" model, the end at the bottom of the picture contains a cam and switch that stops the motor when the antenna is completely UP or Down. The standard model does not have the cup, just a cover, but the mast and motors are the same. I really need a '63-'65 Riviera mast. They were different because about 6" of the guide tube was out of the fender. They get bent and and are next to impossible to straighten and when you do the chrome is often damaged.The mast tube that attaches to the fender opening seems to change from vehicle to vehicle because of the angle of the fender and other mounting considerations, however that is seldom bad on the original and the parts can be interchanged. I am looking for "donors" that are inexpensive because you do not know if the parts are good until you take them apart. (up to $25 plus shipping) There are a few on Ebay but again you do not know the condition and sometimes the shipping is more than the asking price. Link to comment Share on other sites More sharing options...
Guest steveskyhawk Posted February 1, 2013 Share Posted February 1, 2013 Barney said;"If the motor runs but it does not go up or down the plastic line is broken.I rebuild them with a steel cable for $50"The "plastic line" he refers to is called a "tape". The factory used plastic tape because of it non conductivity properties. If Barney is substituting steel for plastic then he is changing the effective length of the antenna. Legnth of an antenna is critical to reception. There is an optimum legnth for every wave length (frequency). The stock antenna is designed to be at an extended legnth that is a compromise for the FM frequencies the radio is designed to receive. This fix of barney's may indeed make the antenna go up and down but may degrade reception of the radio. The cheapest, easiest, and actually the best way to fix a broken antenna is to replace it with a good working used antenna that hasen't been modified. Link to comment Share on other sites More sharing options...
Barney Eaton Posted February 1, 2013 Share Posted February 1, 2013 (edited) When the antenna is up, the steel cable in INSIDE the antenna. The antenna mast itself shields the steel cable from the signal. The steel does not lengthen or shorten the antenna length. It is not grounded on the motor end and makes no change in the performance of the antenna signal.Now explain how the steel cable changes the length of the antenna.If the statment in the above post the was correct, the steel cable, being the same length as the antenna, would work without the antenna being raised. Edited February 1, 2013 by Barney Eaton (see edit history) Link to comment Share on other sites More sharing options...
Guest steveskyhawk Posted February 1, 2013 Share Posted February 1, 2013 The factory used nylon tape to push the antenna up and to retract it as is common knowlege. OEM replacement kits are available which are made with nylon tape as was OEM. The portion of the steel replacement that protrudes from the bottom of the mast and goes around the spool effectively lengthens the antenna. Bad idea to use steel in my opinion but it probably wont have much effect in an area where strong FM signals are present or if stereo is unimportant. Link to comment Share on other sites More sharing options...
Guest Kingsley Posted February 1, 2013 Share Posted February 1, 2013 There have been a number of previous posts on this subject in years past which indicate, and it is my recollection, that the OE antennas did indeed have a wire core in the center of a plastic cable, tape, tube or whatever that you want to call it. I once obtained a number replacement cables, complete with the upper mast section but no wire cores, and did not offer them as I considered them inferior to the OE ones. That pretty well outlines my feeling of this.Perhaps some folks other than the current participants in this thread have some related experience on this subject and can give us the benefits of their comments.Kingsleywww.reattaspecialtyparts - See the Reatta Resource Section of this Forum for my top tier, high quality products. Link to comment Share on other sites More sharing options...
wws944 Posted February 2, 2013 Share Posted February 2, 2013 (edited) The antenna is tuned to be an elementary quarter wavelength vertical antenna in the middle of the FM broadcast band. About 30" at 98 mhz. At the low end of the band, 88 mhz, a quarter wavelength would be about 33", and at the high end, 108 mhz, it would be about 27".With the mast being fed at its bottom, the only thing that matters is its height above its ground plane - i.e., the metal fender it is mounted on. A little extra metal below the feed would have no effect.On AM, the antenna is electrically very short with respect to wavelength. At 1 mhz (1000 khz), a quarter wavelength is nearly 250 feet! (Hence why AM broadcast towers are about that height. The towers themselves are the antennas, with a lot of wire radiating in all directions underground from the tower base to form a ground plane.) Back in the olden days, when dinosaurs and vacuum tubes ruled the earth, car antennas would often have a loading coil at the base of the mast. Very simply put, this helped make up for the extremely short antenna length. Nowadays amplifier gain in the radio itself is used. Edited February 2, 2013 by wws944 (see edit history) Link to comment Share on other sites More sharing options...
Guest Kingsley Posted February 2, 2013 Share Posted February 2, 2013 Walter - thanks very much and I think you have cleared the air quite a bit on this subject. You know some stuff!Kingsleywww.reattaspecialtyparts.com - see the Reatta Resource Section to see the high quality, great performing Reatta parts that we sell. Link to comment Share on other sites More sharing options...
padgett Posted February 2, 2013 Share Posted February 2, 2013 Exacly, the length is what is important, not the core, could use a stick wrapped in tinfoil or a piece of rebar (well capacitance makes a difference in GHZ bands, then you use wave guides). Back in the daze of CB, a 108" whip did nicely for 27 MHz. Link to comment Share on other sites More sharing options...
Guest HessLakeGuy Posted February 2, 2013 Share Posted February 2, 2013 Amazing how much you can learn just by logging onto reatta.org and reading threads like this. Tom Link to comment Share on other sites More sharing options...
wws944 Posted February 2, 2013 Share Posted February 2, 2013 Exacly, the length is what is important, not the core, could use a stick wrapped in tinfoil or a piece of rebar (well capacitance makes a difference in GHZ bands, then you use wave guides). Back in the daze of CB, a 108" whip did nicely for 27 MHz.Right. A 1/4 wavelength at CB frequencies, 27 mhz, is about 109".And Kingsley, you are welcome. After nearly 40 years as a licensed amateur (ham) radio operator, it is like "easy as falling off a log" though. Link to comment Share on other sites More sharing options...
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