voltage checks on sammich

[Technosoul]

Hello everyone.

I have a question concerning voltage checks on the sammichSID. Im using a 9v power supply, all check spots on the main PCB that should be 5V are 4.09 and 9V areas are 6.52. On the front PCB 5V areas are 3.8.

Is this ok, or is something wrong. Please advise, thanks.

[Wilba]

You need more than a 9V power supply^*

I just checked and I don't actually specify or talk about what power supply to use in the build guide, only by accident perhaps:

Note that points labeled “12V” will only be exactly 12V when using a regulated 12V power supply. If

you use an unregulated power supply, the voltage should be 10.5V or more, depending on the current

load. If it drops below 10.5V with SIDs installed, then you may need a power supply that delivers more

current, but not too much current, or the voltage will be higher than necessary and the heatsinks will

get too hot.

If using 6581, make sure you are using a regulated 12V power supply. If using 8580 or 6582, a regulated 12V power supply is preferred but not essential.

The internal 9V regulator (7809) needs more than 9V to regulate down to 9V.

Use a 12V AC 500mA power supply. 12V AC 1000mA is too big, the voltage going into the 7809 will be much higher than required, causing a lot more heat.

Alternatively, use a regulated 12V DC (any current rating) power supply.

* you can get away with a 9V AC 1000mA power supply, because the load is much smaller (300mA), so the voltage going into the 7809 will be 12V or more.

[Technosoul]

thanks wilba.... 12V regulated it is

[Wilba]

If you use regulated 12V DC, see this other post for more info:

[Technosoul]

What a difference with the 12V regulated. All votages came out money, LED is brighter - time for next phase.