It's a CD40 with variable ouput, same as CD60 wich have a second feature added, but the main PCB is all the same as some Philips (CD630 IIRC). It's just a CDM4 & TDA1541A (not R1 like the CD40, strange... R1 is higher spec... ). I guess it sounds the same. But right now nothing can beat my CD-43 wich sounds much cleaner with the melt cap at servo changed...
Matthieu
Matthieu
Why 7809/7909? If you are using a separate transformer then fair enough.
Series regulators (apart from low drop-out or 'LDO' ones) need 2V-3V overhead to actually regulate, at these currents. See the data sheets.
If you must use fixed regs, use 7808/7908. The input voltage is not really high enough to use 9V regulators. 8V is borderline and they'll drop out of regulation when spinning up, etc., but should be OK when playing. When they drop out due to not enough overhead, the output voltage will dip below the regualted value.
Best is to use LM317/337 and set them to 7-7.5V.
Guess who has to work on new year's eve...
In my case it's the HMRC and the chancellor to blame. (The standard rate VAT change...)
And to rub salt into the wounds, everything will be 2.5% dearer when I get up in the morning. (Well, 2.17% actually.)
Grrrr...
Except "lower" priced housing which also got more expensive with the adjustment in stamp duty.
It's all to help the recovery in the economy, don't you know?
Andy
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Clear skies, azure seas and 30 degrees centigrade. Nice work if you can get it.
I know ...
See my other thread ...... http://www.diyaudio.com/forums/lounge/157513-its-hard-life-but-someones-got-do-2.html#post2030831
Andy
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Mmmm.... will it still to put these 7-7.5V regs on the 10V inputs of the servo amps?
That is what I am saying, unless I misunderstood your question.
The '10V' supply is usually up around 11V-12V but depends on your line voltage (mine is higher than spec) but dips when loaded. You should actually measure these whilst playing, to see how much you have here. The servo amps are called upon to produce up to 5V but no more. So they need their supplies to be a volt or two over 5V for a little headroom.
If the regulator is 7V, the regulator has at least 2.5V headroom at its input and the servo amp has 2V headroom at its input.
I made mine adjustable as I didn't know at the time if I'd have to raise the reg voltage if the regs were too hot. I added small heatsinks after this pic anyway (note that the heatsinks must not touch each other unless you use insulators!). I ended up bending one reg forwards and one backwards, so I could refit the cross brace. There is of course no need to put them on the same board as each other.
