Where to take ignition live for stereo from?

[kinga]

Hi all,

Sorry for the real simple question, but could anyone advise me the best place to take a feed from for an ignition switched live to power my stereo on a 68 fastback?

I originally wired it to a live feed so I could have the stereo on without the ignition, but I have fitted a RetroSound and the display is on constantly- not good for battery drain or thieving eyes looking through the car window in the dark - sticks out like a sore thumb!

I was thinking directly from the fusebox, but wasn't sure which connection was ignition switched and hopefully already fused?

Thanks.

[Editor]

It may depend on the power consumption. Check it out and divide by 12 to find the size of fuse it will need. If it's comfortable less than 8 (amps), you could probably connect it to the horn fuse, and use the fuse that's there.

[kinga]

Thanks Dave - the stereo spec says it has a max 15A current consumption during operation and the wiring harness that came with the stereo has a 15A fuse.

[s.unsworth]

I have not looked at my Type 3 Fuse Box today but is there not a Spare / Unused ' Accessory ' Fuse position, where it could be connected with a suitably rated Fuse ?

Steve

[Editor]

There is a spare fuseway on mine, which I use for the clock and an auxiliary power socket. That is a permanently live one, not an ignition switched one.
It's the one used for the FI fuel pump from '68, but that is controlled by the ECU and the fuel pump relay, so the pump is only on when the ECU wants it. If I'm wrong about that, I apologise. It's too dark to go and take a look to be sure!

But be warned, 15 Amps is about half the maximum regulated current your generator supplies! It might be better to consider a separate supply from the battery, and have the relay connected to an ignition-on fuse. A relay takes very little current to switch it. If you connect that load to any of the other power consumers, you may find they are not working properly and at worst, the wiring may overheat and cause damage.

Also, with engine running at a few thousand rpm and driving lights on, you'll probably not be putting much back into the battery. That's why some
owners fit an alternator conversion or a split-charge system and a second battery to run a higher-powered stereo. Our generators can cope with lights, wipers, coil, auto-chokes and a contemporary radio (mine had a 1 amp fuse!), but that's about all without the battery discharging, rather than charging.

[s.unsworth]

Never bothered with Music in the old VWs myself.

Just listen to the Engines !

The Blaupunkt Radio in my '72 Type 3 works but I never use it. It's just there because it always has been.

The '66 Beetle does not have a Radio. The Dash looks neater with the proper Blanking Plate and Chrome Strip running all the way through.

Anyway, off for the MOT on the Type 3 at 08:30 now.


Steve

[jmarkha1]

Agree with Dave re. relay - a safe and reliable way to get the job done.

4 terminals on relay: can buy from eBay or auto electrical shops

30 - 21 amp multicore wire from battery via 16 amp inline fuse.
85 - connect to chassis earth.
87 - connect to your radio power lead with inline 15amp fuse.
86 - connect to any ignition fed power on your fusebox - there should be a spare male spade connector

post some pics when you have fitted

[s.unsworth]

Variant passed MOT, of course. Everything working, including Air Operated Screenwash.

Went for a bit of a local tour after the Test to show it to some enthusiasts at a local Tyre Depot.

Variant is driving really nice while on the move. It just does not want to keep ticking over for very long. Slowly fades and dies. Maybe too Rich on Tickover ? Have currently got just the Manifold Vacuum connected to Distributor and the Carburettor one blanked at the Carburettor end, due to the failed Diaphragm in the Dual Vacuum Unit.

Steve

[jmarkha1]

congrats on the MOT -

Variant passed MOT, of course. Everything working, including Air Operated Screenwash.

Went for a bit of a local tour after the Test to show it to some enthusiasts at a local Tyre Depot.

Variant is driving really nice while on the move. It just does not want to keep ticking over for very long. Slowly fades and dies. Maybe too Rich on Tickover ? Have currently got just the Manifold Vacuum connected to Distributor and the Carburettor one blanked at the Carburettor end, due to the failed Diaphragm in the Dual Vacuum Unit.

Steve

[purplepeter]

Is it just the Yellow trigger wire You wanted to know about?
My Stereo is powered by a New feed to the Battery, with the trigger wire on the Horn fuse

[kinga]

Hi guys,

Thanks for the replies.

On mine the ignition switched feed is red with the constant live feed the yellow wire.

Max power of the stereo is 45W x 4 with RMS of 25W x 4, although I have only connected 2 speakers, so I assume I am using half of that?

I do not have any additional subs or amps, just the stereo and a couple of speakers, so not mega powerful job.

The car is running an alternator.

I would have thought the horn feed should be sufficient at 8A?

If I try it I guess the worst that would happen if it overloaded is that it would blow the horn fuse?

What number fuse is that?

Here's a piccie of the stereo fitted..

[Editor]

Yes, the 8A would do then. As you say, you're only risking a fuse!