Car Radio problems

rlogue

Forgive me for posting this kind of question here but I'm tearing my hair out trying to figure out what's wrong with my new Car stereo..

I replaced the factory supplied radio in my Citroen Xantia with a JVC KD-SC900R CD Radio. This radio also has a DAB receiver added on with a separate DAB aerial.

FM, MW and LW reception comes from the existing rooftop stubby aerial. While FM reception is OK, my MW reception is poor (only the stronger local stations) and LW is non-existent.

Now I had recently had poor LW reception on my previous radio but now I can't get LW at all.

I've replaced the stubby aerial with a longer whip aerial and base, but this has not made any difference to LW and MW. The radio does not seem to need a signal amplifier.

The new aerial can pick up a signal, since if it is unscrewed, the weak MW signal disappears completely.

Is there anything else I should check? I live in London and would want to listen to RTE Radio 1 on LW, and BBC Radio 4 on LW when I'm abroad.

watty

Type of cable between radio and aerial?

Is there more than one aerial socket?

put a 5 turns round internal ferrite rod of portable MW/LW set. Put it in a metal tin, e.g biscuit tin. Try connect the outer and inner of Aerial coax plug to the wire loop you made. If aerial working the radion in buscit tin will work..

Perhaps the MW/LW on a DAB car radio is not much good..

R4 LW fine here in Limerick on my car radio and LW alarm clock.

BBC Devon on MW during day too if I turn off engine!

egal

Hello Richard

I wonder is there a little screw located near to the aerial socket on the radio to "match" the radio to the particular aerial being used, to give optimum reception?

Eamonn.

byte

Radio reception is poor in my car also. I have had the headunit changed too. I am to believe the amp built into the "beesting" aerial (95 Corsa) isn't active. FM is ok if signal is strong but MW and LW is non existant. I'm told beesting aerials are generally crap for MW and LW reception at best of times though I'd still expect SOME reception! :dunno:

The Cush

I recently had the same problem as "byte" with a VW Polo radio fitted with a "bee-sting antenna, weak fm reception, no mw/lw reception.

Some suggestions

1. The VW group (VW/Seat/Skoda) and others now fit the bee-sting antenna as standard.
These antenna have an amplifier at their base which requires 12 volts supplied either by the radio or seperate power inserter via the antenna lead or seperate power lead.
I believe the original head units supply this voltage as standard but an replacement off the shelf head unit may not in which case an adaptor unit may be required to insert the voltage into the antenna lead. The adaptors may be available from the head unit manufacturer or online (some suggestions below)
Example of adaptor http://www.sceniccaraudio.co.uk/Manufacturer.asp?ManufacturerID=179

2. The earth between the antenna base and car body may be bad because of corrosion or paint.

3. In my case it was a broken antenna lead, the previous owner had replaced the antenna base unit, cut and badly resoldered the antenna lead not realising there was a quick disconnect plug about 30cm further up the lead. I now have perfect reception on FM / MW / LW.

This is a useful american site for info about this type of antenna
http://www.corrado-club.com/aktiv/

A forum where you may be able to find some help
http://www.realcaraudio.com/forums/

Some online stores that may stock the adaptors if required
http://www.autoleads.co.uk/index.html
http://www.bluespot.co.uk/default.asp
http://www.caraudiodiscount.com/
http://www.sceniccaraudio.co.uk/
http://www.incarexpress.co.uk/index.php3
http://www.incardiscount.co.uk/index.php
http://www.lowcostcaraudio.co.uk//

An american site that may also be of help
http://www.installer.com/

If none of this helps a visit to a Car Audio installer may be a last resort.

Best of Luck.

byte

Yeah, on further examination I had found a seperate electrical wire going up into the base of the aerial (along with the coaxial lead). I must now find if the wire is being powered by my headunit, so I'm gonna get my hands on an electrical multimeter. If no power, that's the problem. If there is power, then I'd assume the internal amp is kaputt.

Would it make more sense to install an aerial with no internal amp? Or would beesting aerials rely on the amp to make up for the fact they're so small and not as effective as proper telescopic aerials.

The Cush

Would it make more sense to install an aerial with no internal amp? Or would beesting aerials rely on the amp to make up for the fact they're so small and not as effective as proper telescopic aerials.

Its safe to assume that the bee-sting requires the powered amplifier, compare the length of the bee-sting to the extended normal or electric car aerial.

I must now find if the wire is being powered by my headunit,

I assume this should be connected to the "Powered or Electric Antenna" outlet of the headunit, 12v I think. I would suggest you check your units installation instructions for the correct connection.

watty

F = 100Mhz equivalent wavelength = 3m

a 1/4 wavelength whip on a car body gives reasonable match to coax feed cable and performance = 0.75m Allow for end effects, it might be slightly shorter.

The "bee sting" aerials are like "rubber duck" aerials on 27MHz CB or 49MHz walkie talkie, rubbish compared with 1/4 wave aerial.

For MW/LW the aerials are VERY short, the longer the whip, the more signal. Under 0.5m long the MW/LW signal drops VERY rapid. My pocket 144MHz / 430MHz transmitter also receives MW and VHF/UHF from 76..999MHz.

With supplied "rubber duck" (about 3" long!) it does work 144Mhz / 430MHz but poorly. No VHF Band II radio or MW.

With a 7" 144/430 MHz "springy" rubber duck, I get weak Band II Radio and 144/430 improved. No MW Radio

With a telescopic aerial 19" long (1/4 wave at 144MHz) the MW radio works and Band II VHF Radio is fine. 144MHz is excellent. The aerial fully retracted is correct length for 430MHz.

If I stand upstairs at window I can get TV sound on it (600MHz) using any of the three aerials, but poor. A 21 element TV aerial works well though!


Even a foil aerial along window is better than those cosmetic "bee sting" aerials.

The "bee sting" type if designed for mobile phone, will work mobile phone (900MHz approx compared with 100MHz for FM Band II Radio), i.e. aerial can be 1/9th to 1/10th the length required for Band II FM Radio.

"You can't change Physics, Capt'n. The dilithium crystals 'll ne'r take it!"

byte

Thanks for the replies guys. I will look into it over the weekend.

Now would be a good time for Lidl to sell their €5 electrical multimeters!

rlogue

Just as a postscript to all this - I was in the car last night, listened to the radio and reception on MW & LW was quite good. Even Radio 1 on MW was strong enough.

We've had wet weather here lately and I now wonder if my problems are caused by poor earthing. If so, what should I check?

brian boro

Is it possible to replace the beesting aerial on a 1998 Passat?

My AM/LW reception here in N. Mayo is terrible. Intermittent and not great quality BBC FM from Brougher Mt, which I'm sure would improve with a telescopic antenna.

Has anyone tried replacing the beesting and could they give some advice?

Emerson

Richard,
Overall do you notice much of an improvement in RTÉ Radio 1 in London on 252 over the existing 567 tx?

byte

Just to update, I finally got my radio reception sorted.

Got a multimeter, and as thought, the aerial wasn't getting 12v supply. Traced teh problem back to the headunit, and found the wire that was supposed to have 12v wasn't connected. After connecting it up, I now have much improved FM reception (can even now pick up BBC Radio and Q102.2) and have reception on MW and LW too!

Happy days!

ChipZilla

Originally posted by Emerson
Richard,
Overall do you notice much of an improvement in RTÉ Radio 1 in London on 252 over the existing 567 tx?

I was over in Glasgow at the weekend in the car. 252 comes in a lot clearer than 567 ever did.

rlogue

252 is streets ahead of 567 in reception quality.

rlogue

About to collect my car from the local garage - I'll post later about how I got on.

rlogue

Grrrr!!! The garage have proven that the fault lies with the radio, not the car.

Now I have to go back to the dealer again and try and get a replacement radio

kilasser

252 LW excellent here in London

udump

Can anybody help? You guys seem knowledgable.. I have an ipod adaptor and want to fit it to my factory fitted radio (RCD300 in an 06 VW Passat). The problem is that I can't locate the earth point for the flying earth wire - when the units are connected, the ipod is visible to the headunit, but only if I physically hold the earth wire to the chassis, and then only through the speakers on one side of the car. Very safe and comfortable for driving..

When I switch back to CD or radio the speakers work agein. I have tried disconnecting the battery before connecting the unit, but no difference.

Any ideas?

watty

I use a cassette cartridge adaptor for my sony minidisk.

I'm sure there is a better forum for this. It sounds like (and hard to konwe from your description) either the unit is wired wrong or incompatible with your radio.

byte

Sounds like the head unit is only receiving one channel from the stereo output of the iPod.

You sure the audio cable is connected properly? Is it hte right one?

rlogue

I use a cassette adaptor for my iPod, which works fine.

weepee

All Volkswagons leave the factory with a powered aerial. If, somewhere along the line, the factory fitted radio is replaced with a Japanese one, the German aerial will not perform as designed, and only verylocal or national stations can be picked up. MW is simply useless.

To increase performance a booster is required, costing about e3 on ebay.
Check out 'PC5-90' on the internet, and see if it helps your issues-goodluck.

Not sure about the Xsara-sorry.

John mac

5 year old thread!!!!!!!!!!


technology has moved on since then.

fat-tony

Die zombie thread, die :pac: