Building a symmetrical psu B1 buffer

[Salas]

Originally Posted by jean-paul

Thanks for all the time and answers. I won't sink more current as I am very ( too ?) conservative with useless heat and waste power. IMO when people would be somewhat more conscious about energy we would not have the problems we have today in this world. It all starts with small things ...

It will still sound as intended, which is good enough. I don't crank up either. But if someone already has an F5 for instance, will not hesitate... If China will not turn ecological, Polar bear's future is in the big picture anyway.

[jean-paul]

Last week I had an engineer over that had recently installed a large quantity of UPSes in a chinese factory. He told me he was surprised to see mostly 4 stroke scooters in Beijing nowadays. It's a start.

I really hope that they will learn from our mistakes, how hypocrite it may seem. Suppose they make all the same errors...life will be difficult for the whole planet if so.

[woodturner-fran]

Thanks Salas,

I will watch the line voltage over the next few days and see what happens, but that is unusually low. We have had serious rain, of biblical proportions here in the past week with many areas flooded. I know lots of places are without electricity, so undoubtedly all that is connected in with my low line voltage.

I got the source selector switch wired up tonight. I used a 2 pole, 6 position switch, set to 4 positions and I added in some LEDs on the other pole as indicators. I used the 12V supply before the Vdrop resistors for the relays with a 1K in series. Works a charm.

Volume pot is next on the list, then after some listening, get the lightspeed made and hooked up.


Thanks for the help so far.


Fran

[ichiban]

Originally Posted by jean-paul

Last week I had an engineer over that had recently installed a large quantity of UPSes in a chinese factory. He told me he was surprised to see mostly 4 stroke scooters in Beijing nowadays. It's a start.

..far off topic........
Uh, I thought they mostly rode around on bicycles? Scooters sounds like a start, to using more petrol.
I seem to recall reading somewhere that because of the rising incomes Chinese are more likely to purchase an automobile.
..apologies, back to our regularly scheduled topic...

[Tea-Bag]

Originally Posted by woodturner-fran

Thanks Salas,

We have had serious rain, of biblical proportions here in the past week with many areas flooded. I know lots of places are without electricity, so undoubtedly all that is connected in with my low line voltage.


Fran

Fran,
I heard on the news about the flooding problems and rain.

Last month our area set a record for rain for the month, 3x the last record I believe.

[woodturner-fran]

I know - luckily the area I live in is dry - even after all the rain, my yard was dry - not a single puddle!

Lots badly affected though. One shopkeeper said that his insurance used to be 4k, he was flooded 8 years ago (not as badly as this one) and afterwards they wanted to up his premium to 32k - and that had an exclusion for flood damage!! So most o these people are without insurance now.

Yes, back to topic now, sorry for being OT there.....

Fran

[AndrewT]

Originally Posted by udailey

AndrewT's prices are better than anyone out there for matched sets. Not only better but a real bargain.
Uriah

I sell LSK170 in matched pairs to UK buyers. Payments and posting are simply when internal.
I now add a premium to International orders for all the extra work and particularly the travelling to the post office (14miles each way).

BTW.
the B1 and the shunt regulator do not need matched pairs.
The B1 just needs selected Idss. No matching is required.

[DQ]

One quick (very) newbie question. If going for a DCB1 with a Lightspeed attenuator can I use a single 48VA 2x12V transformer for both? If yes, how?

Edit: if not, what kind of transformer would be needed for a Lightspeed linear regulated PSU? Sorry if this derails from the thread topic, but my main question is about integrating the DCB1 with the LS...

[woodturner-fran]

DQ: just look at the wiring diagram on the side of the transformer - join the 2 wires representing the centre of each winding together (=centre tap). Then you have 12-0-12. Check voltages before hooking up.

Thought I'd add a few pics up here.

Sorry for the fairly crappy phone pics.... the wooden front will match my F5.


Fran

[DQ]

Thanks Fran (and by the way congrats for your built). I knew I can get 12-0-12 from 2 x 12-0, but I can't relate your answer to my question, sorry. Knowing so little makes one feel so... stupid

Perhaps I should rephrase a bit. And sorry, while I love music I now very little about electronics as you can easily notice.

The trafo that was suggested to me earlier on this thread gives me 2 x 12V (12-0-12, if you like). Say one secondary rail (did I say it right into English?) goes to the DCB1 PSU positive reg. for instance. The other secondary rail goes to DCB1 PSU negative reg., but also to another couple of bridges and a cap (can be identical the the ones in the DCB1 PSU) that would give me the DC voltage for the Lightspeed. Would such an asymmetry be alright for the DCB1? I think the Lightspeed draws constant current, but I'm not sure.

Also, if the above is OK, would the 48VA power rating of the transformer be enough for both DCB1 and LS?

You may all laugh if this idea is so obviously wrong, but please tell me why.