Modern gizmo's in oldies
Discussion
Excuse my ignorance, but is it possible to fit such things as Sat Nav, C.D.player into an pre-war car?
Obviously I would like to fit very discreetly and easily removable without any damage or marks to the car. I was thinking what sort of connectors I could use if it was possible?
I need these gizmo's as part of the business side of the car.
Obviously I would like to fit very discreetly and easily removable without any damage or marks to the car. I was thinking what sort of connectors I could use if it was possible?
I need these gizmo's as part of the business side of the car.
Assuming it's 12v, You'll need an alternator (instead of a dynamo) but this is a good idea anyway.
It can be difficult to hide new stuff in an oldie (but can usually be done), but it's almost impossible not to leave 'tell tale' signs of it afterwards when you remove the 'stuff'.
If it's 6v I don't know....
It can be difficult to hide new stuff in an oldie (but can usually be done), but it's almost impossible not to leave 'tell tale' signs of it afterwards when you remove the 'stuff'.
If it's 6v I don't know....
crankedup said:
Excuse my ignorance, but is it possible to fit such things as Sat Nav, C.D.player into an pre-war car?
Obviously I would like to fit very discreetly and easily removable without any damage or marks to the car. I was thinking what sort of connectors I could use if it was possible?
I need these gizmo's as part of the business side of the car.
CU, your biggest problem is that all modern equipment runs on a negative earth system, whereas almost all older cars with dynamos are positive earth.
You can convert before you fit an alternator but you have to be careful with some of the instrumentation on older cars; if you don't get it right and short them out it could be that they are irreplaceable.
There is no way that a dynamo could power a modern CD player let alone satnav, so you might need to do a bit of engineering with brackets etc, to get an alternator to physically fit the engine block.
If it's a particularly valuable car you also have to consider the consequences of tampering with originality.
One way to make an alternator look better on an old engine is to simply paint it with engine enamel so that it blends in to the overall view under the bonnet.
A great many CD players now come with a plug and a few inches of wiring so that you can integrate it into the wiring loom without too much hastle; I'm reasonably sure Satnav systems will be the same.
I'm surprised to see people saying that a dynamo won't be up to the job. If it can run the headlights when it's dark, it can certainly run a CD player. The actual playing mechanism only takes a few watts. The amplifier can take considerably more, but only for short bursts which will be covered by the battery - the average power of a music signal is generally an order of magnitude less than the peak power. Also, the power outputs quoted for self-contained stereos are invariably a big fat lie - not quite as bad as the hilarious figures quoted for PC speakers, but still a lie.
Of course, if you want to fill the boot with laxxer amplifiers, it's a different matter, but I'm assuming you don't
Converting a positive earth car to negative earth is a piece of piss. Reverse the battery, flash the dynamo, reverse any polarity-sensitive instruments (ammeters, voltmeters), job done. Sometimes you may need to reverse the LT connections to the coil. The great thing about pre-electronics cars is that things are not polarity sensitive and apart from the odd instrument will work just as well either way round. The most awkward thing that's likely to happen is that the battery earth lead won't reach with the battery reversed
Having said all that, an alternator conversion is still a good idea for reliability reasons. It may also be less electrically noisy than a dynamo.
Incidentally, it is possible to convert an alternator to positive earth. I did it when fitting an alternator to my Morris Minor (to run driving lamps), because it was easier than converting the radio to negative earth. Not by much though
Of course, if you want to fill the boot with laxxer amplifiers, it's a different matter, but I'm assuming you don't
Converting a positive earth car to negative earth is a piece of piss. Reverse the battery, flash the dynamo, reverse any polarity-sensitive instruments (ammeters, voltmeters), job done. Sometimes you may need to reverse the LT connections to the coil. The great thing about pre-electronics cars is that things are not polarity sensitive and apart from the odd instrument will work just as well either way round. The most awkward thing that's likely to happen is that the battery earth lead won't reach with the battery reversed
Having said all that, an alternator conversion is still a good idea for reliability reasons. It may also be less electrically noisy than a dynamo.
Incidentally, it is possible to convert an alternator to positive earth. I did it when fitting an alternator to my Morris Minor (to run driving lamps), because it was easier than converting the radio to negative earth. Not by much though
Pigeon said:
I'm surprised to see people saying that a dynamo won't be up to the job. If it can run the headlights when it's dark, it can certainly run a CD player. The actual playing mechanism only takes a few watts. The amplifier can take considerably more, but only for short bursts which will be covered by the battery - the average power of a music signal is generally an order of magnitude less than the peak power. Also, the power outputs quoted for self-contained stereos are invariably a big fat lie - not quite as bad as the hilarious figures quoted for PC speakers, but still a lie.
Of course, if you want to fill the boot with laxxer amplifiers, it's a different matter, but I'm assuming you don't
Converting a positive earth car to negative earth is a piece of piss. Reverse the battery, flash the dynamo, reverse any polarity-sensitive instruments (ammeters, voltmeters), job done. Sometimes you may need to reverse the LT connections to the coil. The great thing about pre-electronics cars is that things are not polarity sensitive and apart from the odd instrument will work just as well either way round. The most awkward thing that's likely to happen is that the battery earth lead won't reach with the battery reversed
Having said all that, an alternator conversion is still a good idea for reliability reasons. It may also be less electrically noisy than a dynamo.
Incidentally, it is possible to convert an alternator to positive earth. I did it when fitting an alternator to my Morris Minor (to run driving lamps), because it was easier than converting the radio to negative earth. Not by much though
Hi Pigeon,
A modern CD player with a multidisc changer actually does use a bit of power, the problem being that the dynamo simply can't charge the battery quick enough, particularly in modern traffic with lots of slow running and long idling periods.
Satnav also runs a transceiver, so if you were using both at the same time the poor old dynamo wouldn't stand a chance.
Aston Martin used to run positive earth systems with alternators because there was a theory that it cut down electrolysis between the alloy body and the steel chassis mounts.
The problem with this is that you just can't buy any accessories nowadays made with positive earth polarity.
Incidentally, I did a lot of conversion work like this in the '70s when alternators were becoming standard equipment and with some older cars you had to be very careful with some of the instruments because they used the steel binnacle casings as earth, so if you reversed the contacts and then connected the battery you instantly fried the instruments and the loom up to them; very nasty!!
So with some you had to either have the instrument rebuilt or insulate the casing with a plastic sheath.
IOLAIRE said:
Hi Pigeon,
Hi again
IOLAIRE said:
A modern CD player with a multidisc changer actually does use a bit of power, the problem being that the dynamo simply can't charge the battery quick enough, particularly in modern traffic with lots of slow running and long idling periods.
Satnav also runs a transceiver, so if you were using both at the same time the poor old dynamo wouldn't stand a chance.
I must admit I am not totally up to speed on the more upmarket equipment such as changers. People usually have them fitted by the supplier. It's the lesser models that they try to fit themselves and then ask me to sort it out
(whoever thought black for positive and brown for ground was a good colour scheme for wiring looms has an awful lot of blown fuses and charred diodes to answer for!) For a CD drive, single or multi, to use more than a few watts continuously (as opposed to changing discs) seems a remarkably extravagant use of power to me... it has to be said though that electrical accessories designed for modern cars are not exactly shining examples of low power design
Next time I get my hands on a changer I'll measure its power consumption, for you have intrigued me. Re satnavs, you mention transceivers - so they actually communicate two way then? I was expecting them to be basically GPS units with a high quality display; since a GPS receiver runs happily for ages off AA cells, I was expecting a consumption of maybe 10 watts, dominated by the display backlight.
IOLAIRE said:
Aston Martin used to run positive earth systems with alternators because there was a theory that it cut down electrolysis between the alloy body and the steel chassis mounts.
Ah yes, endless fun with this one... It should do, but people go on for ages about whether it does or not, and in some cases swap it because they think it's the wrong way round... I reckon that as most cars spend much more time parked up than being driven, with the electrics off, it's the corrosion that takes place when parked that dominates, so if people want to worry about something better to concentrate on washing the salt off.
IOLAIRE said:
The problem with this is that you just can't buy any accessories nowadays made with positive earth polarity.
True... It is good earthing practice to connect the case of the device to the earthy side of the power supply at the point where the power supply enters the case, and nowhere else. If the unit is actually made like this, conversion is trivial. Unfortunately, though, very few are... I have a certain fondness for the old units that not only were made like this, but had a plug on the back to select positive or negative earthing.
IOLAIRE said:
Incidentally, I did a lot of conversion work like this in the '70s when alternators were becoming standard equipment and with some older cars you had to be very careful with some of the instruments because they used the steel binnacle casings as earth, so if you reversed the contacts and then connected the battery you instantly fried the instruments and the loom up to them; very nasty!!
So with some you had to either have the instrument rebuilt or insulate the casing with a plastic sheath.
...and if the instrument designer had a nasty sense of humour, both terminals are mounted on insulating washers but one is nevertheless connected to the case internally...
You have reminded me that I overlooked the instrument voltage regulator... probably not a worry if we limit the discussion to pre-war cars, but speaking of positive-earth cars in general it's probably worth checking whether it uses a Zener diode. If so it will need replacing, but a homebrew replacement is trivial, cheap and can be removed to revert to original if desired.
Hi fella's, only wanted a bit of music in the ole girl
Its clearly not quite a simple job as I had hoped for. Maybe I may be better off looking for a battery powered player that portable and forget sat nav.
Still its brought a very interesting discussion and good points made. No matter what is asked PH'ers always provide answers.
The car in question is at Orchid Cars, the Vauxhall LM. Going to have a look on Wednesday.
Its clearly not quite a simple job as I had hoped for. Maybe I may be better off looking for a battery powered player that portable and forget sat nav.
Still its brought a very interesting discussion and good points made. No matter what is asked PH'ers always provide answers.
The car in question is at Orchid Cars, the Vauxhall LM. Going to have a look on Wednesday.
nice loking car, suprised you didn't go for this though
www.orchidcars.co.uk/PedalCar_spec.html
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