ianhayward

I'm still trying to get to the bottom of why the Blaupunkt Casablanca CD51 radio CD I fitted to my 1999 Impreza Sport does not dim the display when the lights are on.

According to the supplier Blaupunkt 's helpline say the problem is with the illumination signal from the Scooby being a simple high/low voltage change, rather than a pulsed system (as used by most other manufacturers).

Anybody know anything about this?

Is it true? (Why use a pulsed system? Sounds unnecessarily complicated!)

PS my thanks to those who replied to my earlier post on this matter!

chiark

Sounds like confirmed bollocks from Blaupunkt to me. The ISO standard is for a line to go high when illumination is on...

Jaggy Bunnet

You don't have the BRIGHT button pushed in, do you?

JB

ianhayward

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Jaggy Bunnet:
<B>You don't have the BRIGHT button pushed in, do you?

JB[/quote]
Is this a wind-up? I thought the BRIGHT button just altered the little clock brightness.

By the way, I spoke to Blaupunkt technical today. According to them, most European cars produced over the last 7 years or so use a pulsed (square-wave?) signal to indicate dimming. Presumably you can alter the brightness of the display by altering the spacing of the pulses. They did this because LEDs don't like being partially lit, but do like being switched on and off rapidly.

Does anybody know of a supplier of a converter cable that chops the constant voltage (Scooby) signal into pulses?

Otherwise I have to get out my soldering iron and a 555 timer chip (appropriate number for Subaru!).