Got a nice little VIC in the mail today.

ral-clan · Post by **ral-clan** » Tue Feb 26, 2008 9:45 am

Okay, I've added some of the pictures (and info) provided by Boray to the WIKI article on VIC-20 power supplies:

http://sleepingelephant.com/denial/wiki ... r_Supplies

Thanks Boray!

I think we now have info on ALL the power supplies made for the VIC-20.

Again, if any of the technical info is wrong or missing, please feel free to let me know or edit it yourself. I am a collector of information on the VIC-20 but not a electronics expert.

Mayhem · Post by **Mayhem** » Wed Feb 27, 2008 1:46 pm

Okay spanner in the works time... my Vic20 UK two prong supply looks like the 1001038-02 version in the Wiki but it has part number 1001038-03 on the label at the back... and it matches the 02 regarding in and out power.

Perhaps it's more to do with region than type?

ral-clan · Post by **ral-clan** » Wed Feb 27, 2008 2:19 pm

Mayhem wrote:Okay spanner in the works time... my Vic20 UK two prong supply looks like the 1001038-02 version in the Wiki but it has part number 1001038-03 on the label at the back...

Neat. Seems Commodore just re-used a lot of product numbers, even when re-designing the power supply completely. You'll notice there are also two completely different power supplies both with product no. 902502-02.

and it matches the 02 regarding in and out power.

Are you sure? That seems VERY strange. How could a UK power supply have the same power input-output specs as the 1001038-02? Those are 110V specs which would blow up on the UK power grid.

Unless it's a swichable power supply (switch inside the case?) and they just forgot to put on a new label for the European market.

Could I get a photo of your power supply to add to the WIKI with the label & part no. clearly displayed (or you can do it). I have added your info about a metal cased 1001038-03 to the WIKI article.

I agree that the -02, -03 suffixes at the end of the product numbers probably reflect regions, or maybe voltage types, rather than model revisions.

But what does the -01 on the end of one of those N. American power supplies mean then?

(Only us VIC-20 enthusiasts would ever be interested in this stuff!

)

Mayhem · Post by **Mayhem** » Wed Feb 27, 2008 3:09 pm

I'm not sure why I put "in" there... but the output definitely states VAC 11V, 38VA. I'll try and take a pic the next time I have it in my hands (most of my Vic stuff is elsewhere currently).

The bizarre thing is, my Vic20 is not that low a serial number but yet has the two prong input. Unless all the US ones made pushed the base number up for the PAL release...

carlsson · Post by **carlsson** » Thu Feb 28, 2008 3:19 am

I believe my boxed 2-prong VIC-20 has a serial number 6xxx. That is not impressively low though. It came with the common keyboard and a 9VAC 27VA power supply. (oops.. I was going to write 27A first)

ral-clan · Post by **ral-clan** » Thu Feb 28, 2008 6:53 am

carlsson wrote:I believe my boxed 2-prong VIC-20 has a serial number 6xxx. That is not impressively low though. It came with the common keyboard and a 9VAC 27VA power supply. (oops.. I was going to write 27A first)

This is going to sound strange coming from a guy who just put together the Denial WIKI article on power supplies, but what is the difference between A and VA?

(I did say above I am somewhat clueless when it comes to electronics).

6502dude · Post by **6502dude** » Thu Feb 28, 2008 7:53 am

"A" is abbreviation for Amps (Amperes).

The notation VA is intended to represent Volt-Amps.

The product of Volts multiplied by Amps is Watts.

Therefore, the 9VAC - 27VA power supply is capable of delivering about 3 amps.

Mike · Post by **Mike** » Thu Feb 28, 2008 7:56 am

ral-clan wrote:power supplies, but what is the difference between A and VA?

1 A is the SI-unit for electrical current, i.e. the amount of electrical charge which flows in 1 second.

1 VA is a unit derived from SI, 1 Volt x Ampere. For Alternating Current it specifies the so-called 'apparent power'. That means, if a load is connected to the wall outlet, and you measure x Volts AC in parallel, and y Amperes AC in series to the load, then the load takes x * y VA apparent power. If there's a transformer in between, it must be rated to cope with this power. Otherwise it might overheat.

Michael

carlsson · Post by **carlsson** » Thu Feb 28, 2008 7:59 am

Voltage (V)
Amperage (A), current

VA is simply V*A, better known as W (watt). I think the difference in this case is that VA is how much effect the device consumes, while W is how much it produces.. or vice versa. Someone should correct me here.

ral-clan · Post by **ral-clan** » Thu Feb 28, 2008 8:25 am

carlsson wrote:Voltage (V)
Amperage (A), current

VA is simply V*A, better known as W (watt). I think the difference in this case is that VA is how much effect the device consumes, while W is how much it produces.. or vice versa. Someone should correct me here.

Thanks guys for the quick replies. I'm trying to absorb it all, but the explanation that 1VA = 1W seems clearest to me. Not sure why they don't just say 1W though...?

Mike · Post by **Mike** » Thu Feb 28, 2008 9:06 am

This is because 1W, and 1VA are indeed two different things.

With alternating current, there are actually three types of power involved:

1 W, which is active (or real) power,
1 VA, which is apparent power, and
1 var, which is reactive power.

An Ohmic load (like a resistor) only consumes active power. In that case, voltage, and current are in phase. Ultimately, this power is converted into heat, or other energy forms, and lost.

A reactive load (like a capacitor, or an inductor) ideally only consumes reactive power. Voltage, and Current are out of phase by 90 degrees. Reactive power builds the electrical field inside the capacitor, or the magnetic field of the inductor. As the current is alternating, the reactive power flows back, and forth between source, and load. With an ideal transmission line, the power would not been lost as heat.

A mixture of both types of load results in something that takes an apparent load.

For an ideal transformer, the product of Voltage, and Amperes at input, and output is always the same. Take a load of 9 V, 1 A alternating current, i.e. 9 VA. You wall outlet might have 110 V. The transformer needs to have a transforming ratio of:

9 V_out = 0.082 * 110 V_in

The input current will be transformed with the reciprocal value to keep the product 9 VA constant:

1 A_out = (1/0.082) * I_in => I_in = 0.082 A.

The transformer, however, is not ideal. Some of the electrical energy flowing through is converted into heat. The rub here is, that it doesn't matter which type of load (active or reactive) is connected as load. Therefore they are rated in VA, which they can cope with without overheating.

The transmission lines are also not ideal. The reactive power performs no useful work, but some of it is indeed lost as heat in the transmission lines, and transformers. The power supply companies therefore take an interest to minimize the reactive power their costumers take from the grid.

Michael

P.S.: I had to stop here before this ends up as basic course in electrical engineering.

dave01253 · Post by **dave01253** » Sat Mar 01, 2008 3:41 am

I have some pictures of power supply units ( and other stuff )

I wonder if you'd give me some info about the black transformer

http://www.dchester.pwp.blueyonder.co.uk

follow the links

ral-clan · Post by **ral-clan** » Sat Mar 01, 2008 8:13 am

dave01253 wrote:I have some pictures of power supply units ( and other stuff )

I wonder if you'd give me some info about the black transformer

http://www.dchester.pwp.blueyonder.co.uk

follow the links

That's interesting. It seems to be a European/UK version of 251053-02. Can I use your picture in the Wiki article? Actually, if you could take one with the connectors showing that would be more informative for the WIKI (otherwise it just looks like the US version).

dave01253 · Post by **dave01253** » Sat Mar 01, 2008 10:51 am

Use the pictures as much as you want. The power supply is a din plug one. The plug is certainly not shiny any more which makes me believe its old. Tell me how to pose for the pictures then and I'll get right on it!! I'll clean it up first !

ral-clan · Post by **ral-clan** » Sat Mar 01, 2008 3:35 pm

dave01253 wrote:Use the pictures as much as you want. The power supply is a din plug one. The plug is certainly not shiny any more which makes me believe its old. Tell me how to pose for the pictures then and I'll get right on it!! I'll clean it up first !

If you could just take a photo similar to the other ones. I.e. a 3/4 perspective view from above....with the connectors put nearby. You can either link it here, e-mail to me, or even put it in at the bottom of the article yourself. Thanks!