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svxistentialist
10-15-2003, 04:36 AM
Has anyone any experience with the above?

I would be obliged for any information you may have, suppliers, prices etc, and most importantly, does it work, and work well.

Phil, I know you fitted one, and I emailed your supplier Elite International, with no reply yet.

A company in NZ recommends using two in the case of our Diversity system. They would need to be very closely matched frequency wise to be a success. I know Phil you had bad reception when fitting one originally. Did you fit a second one, or disconnect the secondary aerial input?

Also, the electronics whizzes in NZ say that the expander needs also to have a filter to eliminate signals in the Japanese sector of the waveband. Does/did yours have this?

Last point, does the expander cover the full 88-108 spectrum, and if so, which blank points of no reception are there on the set-up?

TIA

Joe:)

b3lha
10-15-2003, 05:53 AM
Hi Joe,

We still have the one band-shifter connected to the mast aerial. I've been meaning to follow your suggestion and unplug the window aerial but haven't got around to searching for the join in the cable.

The result, as you know, is that whenever a signal appears on the Japanese sector, the radio reception drops out. I'm not sure who uses that frequency band here, but sometimes I can hear faint talking, so I think it must be phones, CB or emergency services.

I don't know if it has a filter or not.

There is a switch to select whether you want to offset the frequencies by 10Mhz or 20Mhz. To get 95.8, you have to put the switch in the 10 position (maps to 85.8), to get 106.2 you have to put the switch in the 20 position (maps to 86.2). This is a real P.I.T.A. since the switch is mounted in the boot. (We usually just leave it set on 20)

I wish we had just bought one without a switch which just shifts the frequencies by 15MHz. Look carefully at the stations you want to receive and choose a device with the right offset.

When we discussed this before, somebody said that the window aerial is much better than the mast. If only using one shifter, maybe it's better to put it on that one and unplug the mast.

Am I right in thinking that the UK cars have a button to extend the mast aerial and presumably they can use the window aerial and only extend the mast in areas of bad reception?

b3lha
10-15-2003, 05:57 AM
The band shifer on the Elite International Website does not appear to have a 10-20 switch - maybe they changed the design.

http://www.svashop.com/

svxistentialist
10-15-2003, 06:21 AM
Thanks Phil

This sva website is the same as the Elite Int that I have emailed, and await reply.

You might have a look at the info on this site:
http://www.edl.co.nz/ConvertersHP/PRODUCTS.html#1

The one I have selected as appropriate for me is the PBS2000AUS. It shifts by 12Mz in the lower band, and automatically by 24 for the upper reaches. It gets no signal at 96 or 108, but locally here there are no stations I need to receive at those numbers. They seem to plug these shifters in at the back of the radio, and imply that diversity radios have two sockets at the back, into which you plug the convertors and plug the aerial leads into the devices. Is this correct for ours? Did you have the radio out?

Also, I don't think it's correct the window aerial is stronger, rather the other way round. Info from these guys suggests the window aerial is selected by the diversity signal if the mast signal is local and too strong. In which case if true, you would be better unplugging the window aerial, and let the mast with the shifted signal do it all.

Joe

b3lha
10-15-2003, 08:05 AM
Originally posted by svxistentialist
You might have a look at the info on this site:
http://www.edl.co.nz/ConvertersHP/PRODUCTS.html#1

Interesting Site. Their devices appear to be a lot more sophisticated than the one we have.

They seem to plug these shifters in at the back of the radio, and imply that diversity radios have two sockets at the back, into which you plug the convertors and plug the aerial leads into the devices. Is this correct for ours? Did you have the radio out?

I think you are correct that the radio has two aerial sockets. We asked the guy who fitted the alarm to fit the converter to the back of the radio, but he couldn't figure out how to gain access to the back of the radio. So I installed it next to the mast aerial, which was a much simpler job.

The converters have male and female coax connectors so they can fit inline between the aerial and the radio. Then all you need is a 12v power source. I think the grounding is done via the sheild on the coax.

Jamsvx
10-15-2003, 07:20 PM
Em......would it be easier to get a radio from a wrecked Euro/UK SVX??

Or do you have the steering wheel mounted controls??

Trevor
10-16-2003, 02:29 AM
Originally posted by b3lha

I think you are correct that the radio has two aerial sockets. We asked the guy who fitted the alarm to fit the converter to the back of the radio, but he couldn't figure out how to gain access to the back of the radio. So I installed it next to the mast aerial, which was a much simpler job.

The converters have male and female coax connectors so they can fit inline between the aerial and the radio. Then all you need is a 12v power source. I think the grounding is done via the sheild on the coax.

I doubt that it will work as well connected at the areial due to matching problems and losses in the coax. Often they can be fitted without removing the radio if the set has a flying lead and aerial socket as many do
which can be accessed from the side or from below.

Thousands of used cars have been and are being imported every year into this country, hence the demand and development of these band expanders. I have one in my SVX but my OEM receiver uses only the rear mounted external aerial and there is no window aerial.

svxistentialist
10-16-2003, 03:36 AM
Originally posted by Jamsvx
Em......would it be easier to get a radio from a wrecked Euro/UK SVX??

Or do you have the steering wheel mounted controls??

Not a bad idea at all James.

Mine has the steering wheel controls, and I like them. Not sure about Phil & Belha's. They have a multichanger CD in the boot, so maybe they don't have the steering wheel controls.

Joe

b3lha
10-16-2003, 04:12 AM
Originally posted by svxistentialist
Mine has the steering wheel controls, and I like them. Not sure about Phil & Belha's. They have a multichanger CD in the boot, so maybe they don't have the steering wheel controls.


Yeah, we have them too - and they're essential: I find the radio controls to be very user-unfriendly. The volume knob is so close to the side of the compartment that you can't grab hold of it. The treble and bass knob is really nasty, and there's at least one button I haven't found a purpose for. The tape deck and CD player are nice though.

The multichanger is great, but bumps, corners and condensation play havoc with it. I've also noticed occasional damage (cracks) appearing in some of the CD's that we play in it. Anybody else have that problem?

svxistentialist
10-16-2003, 04:23 AM
Well the single disc dasboard player I have does not seem to do any damage to the discs.

If there is one fault with the player, it is an older type that does not have a big buffer memory. When you hit a bump at times it stops. Other than that, an excellent player.

Joe

Jamsvx
10-16-2003, 07:32 AM
Lucky you!!

I would have to agree that the radio/cd controls are very fiddly in their 'cave' - would have been excellent to have steering controls across the range.

Mine is skipping a bit and tends to heat up - If I end up keeping it, I would like to put something like a Nakamichi deck in - yum!

svxistentialist
10-17-2003, 01:37 PM
Phil,

The EDL place in NZ mailed me back, but their price is quite high. Just found a place in Dublin that has them, Digicom Electronics, at E25 each not incl postage. This is about £17.40.

They say it covers the whole spectrum, 88 to 108, and there are no "known" blank spots affecting Irish stations.

This worries me a little, the way these things work, there has to be one or more blank spots, laws of physics and all that. However, there could be a blank spot, and no Irish station broadcasts at that point, so it would then become irrelevant.

I am going to buy two, and fit behind the radio. Let you know how it works.

Anyone know how to get the radio out??:eek: :D :D

Joe

svxistentialist
10-17-2003, 02:06 PM
Found an interesting file in the How To. Shows how to get the radio out and so on. Phil, you might be interested in this. The two aerials are terminated at the left side of the transmission tunnel using what are described as Motorola terminals.

See

http://www.geocities.com/svxdc/AudioInstall-2.htm#2.3.2-DisconnectAntenna

Check picture 2
This would be an ideal place to site the two expanders. All it needs is an accessory 12v wire to power them up when the radio is on. It would mean soldering on Motorola male/female ends, instead of the push in plugs, but that might be handier than taking out the radio.

Worth a try anyway.

Joe:)

Trevor
10-18-2003, 09:03 PM
Hi Joe,

You will not experience any blank spots. There is simply a shift in the frequency of the band width being covered by the range of tuning available.

The twin aerial diversity set up is something you may have trouble with. We do not use any such system and I have no exact details. It is likely that the output frequency of two separate expanders will not be exactly the same and this could cause problems. The sort of variation I would expect would not be of consequence in normal use.

What happens if you connect only the vertical aerial, is FM reception still OK ? If so you could simply work accordingly using one expander.

Regards, Trevor.

svxistentialist
10-19-2003, 02:11 AM
Thanks Trevor.

The more expensive ones from NZ have an integral filter to stop signal in the Japanese portion of the spectrum. This would stop the stray effects that Phil is getting, picking up taxis etc that use the lower spectrum here.

Apparently, the cheaper ones do not have a filter. You are also right about the twin aerial diversity set-up. I have already suggested to Phil to unplug the window one, which is for selecting the weaker signal when required.

The diversity system would be of most use in a city environment, when signal strength variatrion is at its worst, ie too strong on one street, too weak on the next. I am going to put on two of the more expensive ones, they are meant to be frequency matched. There's only a difference of about 20 Euro for the dearer ones, and I will have the radio working at its best [in theory:rolleyes: ]

Joe:)

Trevor
10-19-2003, 09:38 PM
Hi again Joe,

I do not understand how signals are being picked if they fall within the original Japanese tuning band width. The connecting cable between the expander and the tuner should be fully shielded so that no signal should be available at the tuner frequency. The only signal available should be as modified by the expander.

I gather Phil has his expander remote in the boot close to the vertical aerial. The long lead in may be providing a means of entry for signals at the original frequency direct to the receiver. Earthing of the lead in shield could be faulty resulting in an earth loop. The shield as part of the vertical aerial must be in contact with the body shell at the entry point of the aerial and also to the receiver aerial socket earth.

If he has the expander case earthed separately in the boot he should try removing this connection so that there is earth and negative connection only via each end of the cable shield. This could otherwise be providing an earth loop condition. If the expander is provided with a designated earth lead this suggestion will not apply.

Regards, Trevor.

b3lha
10-20-2003, 12:46 AM
Originally posted by Trevor
Hi again Joe,

I gather Phil has his expander remote in the boot close to the vertical aerial. The long lead in may be providing a means of entry for signals at the original frequency direct to the receiver. Earthing of the lead in shield could be faulty resulting in an earth loop. The shield as part of the vertical aerial must be in contact with the body shell at the entry point of the aerial and also to the receiver aerial socket earth.

If he has the expander case earthed separately in the boot he should try removing this connection so that there is earth and negative connection only via each end of the cable shield. This could otherwise be providing an earth loop condition. If the expander is provided with a designated earth lead this suggestion will not apply.

Regards, Trevor.

I understand what you're saying regarding the positioning of the expander, but I think that my problem stems from having two aerials connected to the radio, but only one of them via the expander.

I believe that the window aerial is allowing signals in at the original frequency. The reason I think this is that I never get the signal and the noise at the same time. We can be listening to a clear UK radio signal and then suddenly it will drop out completely and we will hear something else. After a few seconds, it will flip back to the UK signal. This suggests to me that the radio is switching between aerials due to a stronger signal in the Japanese spectrum.

I intend to unplug the window aerial, as Joe suggested so the radio will only ever see the converted signal from the vertical aerial. I expect that to fix the problem.

Joe - I can confirm that the aerial leads are under the carpet on the left (passenger) side of the transmission tunnel in our RHD cars - the same as the LHD cars.

Phil.

Trevor
10-20-2003, 03:52 AM
Hi Phil,

I was not aware that you had two aerials connected. You are exactly right. The aerial without the expander will be delivering signals at the original frequency on top of the signals from the expander.

Regards, Trevor. :)

b3lha
10-27-2003, 03:48 AM
I've unplugged the window aerial at the connector in the passenger footwell. This has successfully cured the interference problem.

svxistentialist
11-08-2003, 10:37 AM
Hi Phil

Glad that cured your problem.:D

I have been away up North a few weeks, and off-line all the time, so had no time to follow this up.

Will post details when I have some news.

Joe:)