Tuner faults with MD car head units

[andy29]

Hello, I often have thoughts of buying an MD car head unit... I tend to be attracted to ones like the Sony MDX-C7900, C5970 etc. because they seem to be from the same kind of generation as my XR-C5100R. But I've seen that some (on the European versions at least, and I am in Europe) commonly have faults with their radio tuners. What is it that actually goes wrong with them? It doesn't sound good.so it's possibly pointless asking, but it is fixable in any way at all or it is just terminal for the radio? Would they still be able to receive a car FM transmitter right next to them if they've gone 'weak'?

[sfbp]

The only variation in head units is the tuner module which is different for Europe, Asia, and N. America, and Japan.

Different spacing, different bands. I don't think there's a single one that works worldwide, the exception to the general rule being some Onkyo bookshelf units, which doesn't help you.

I can tell you it's possible to swap them (at least in the case of a bookshelf type unit) because I did it. Not sure how modular the car-fi is as it's a bit more crammed. The worst differences are: Japan doesn't go above 90MHz for VHF, and AM has strange bands which are sometimes 100kHz off (though it works). Could it be that you read of someone trying to use the wrong unit on European airwaves?

[andy29]

Hi sfbp, thank you. I'm sorry because I probably didn't explain properly, but what I was meaning is how in various places (eg. eBay) I've seen slight variations on how the tuner circuits are 'weak', how the chips 'burn out' and how they become unable to recieve any signals - some ads for units clearly state how they have the 'common problem' with the tuner. Supposedly only on the European ones. Some say it's intermittent. When it's mentioned it's often said as if it's a well-known problem, so it makes me wonder where that idea comes from. It would be interesting to know what the problem really is. Because if it's actually components and not the chips, maybe it could be repairable. But I can't find anything about it online at all.

[sfbp]

You were clear, but I could only think that the reports were due to something else. Sony's stuff is reliable, but faults are often misreported

Isn't VHF going the way of the dodo in Blighty?

[andy29]

Oh ok True, there's no set date yet but they seem to be eager to switch over to DAB, so FM will be gone eventually and I look forward to listening to music in glorious 80 kbps mono MP2. It would be good to still be able use an FM transmitter to get something into it, but that depends on what this problem really is. I know it's a bit of a cheat though, and obviously the MD part is the most important.

I see what you were thinking with how it's maybe a different problem... who knows... I feel like I might need to ask one of the sellers where they got their information from and what exactly the unit does.

[sfbp]

The FM transmitters for head units are REALLY HORRIBLE, in my not so humble opinion. I got an MD changer with this option and it lasted 3 weeks before I ditched it for the Unilink thing. Bluetooth, OTOH is much much better in modern cars - all one really needs.

The perfect head unit (which will never be built) will be HiMD with Cell-based internet. However, if you get the NW-F88x series flash player, provided you get the Japanese version, you're good to play back ATRAC into your Bluetooth-capable headunit. And that works a treat, I have rented cars all across Europe and serenaded myself from the NW-F887 (note that the NWZ-F887 etc doesn't cut it, since it doesn't have ATRAC support).

Oh yes, the other thing about radio receivers and tuner modules is that the channel spacing is different here in Amerique du Nord, 200Khz instead of 50kHz. IIRC they always had something here called side bands (esp on VHF TV which is now gone too) and so you couldn't have 105.6, 88.2 or any other such thing, only the odd ones like 105.7 and 88.1 (our two CBC radio channels still). I have a head unit in wife's car that came from HK and it's no big deal to avoid the FM "even" channels. However AM is more of a problem, the channel separation is, I think, 90 in HK (and probably elsewhere) whereas here it's 100. YMMV. It's so long since I used AM in UK that I can't recall the details. This is a real pain as you really cannot hit some local stations right on the middle of the band.

I was really surprised when someone moved R4 to LW (from MW) a few years back.

 

[andy29]

I didn't even realise there were ATRAC players like that. I admit I am using a bluetooth to FM transmitter at the moment because it's the best I can do unless I'm playing a tape! I know it's rubbish but it's better than nothing at the moment. I guess there are always the semi-serious 12v FM transmitters and good bluetooth receivers if anyone fancies a project. I always wondered if it was possible to somehow get the unit to take an input from the phono sockets where you would plug in an MD or CD changer, but I think you would need to do something about the control connection. But maybe something like an Arduino could be used to fool it into thinking it's talking to a changer? But by the time you've done that it probably easier to mod the thing inside for a line input.

Yes it's a shame that the band spacing is done differently, otherwise I suppose the tuners really would be interchangeable.

[bluecrab]

My C7970 has been good to go since I installed it a number of years back. Certainly it's been an improvement over the tuner section in the prior head unit, a CA680X. Oh, that was a nasty one. Car's the same for both: 2006 Ford Escape AWD.

[sfbp]

1 hour ago, andy29 said:

Yes it's a shame that the band spacing is done differently, otherwise I suppose the tuners really would be interchangeable.

Actually the *tuners* are. Sony engineered them cleverly so that the dependencies are in the tuner module. But with head units it's a bit of a pain because everything is packed in there.