Building a symmetrical psu B1 buffer

[KatieandDad]

Little Buggers are not easy to photograph.

I've tried my best - see what you think.

They definitely look "brushed" to me. That would be my first clue that they have been remarked.

[Salas]

Fakes.

[KatieandDad]

Let's hope that Dalbani will try to honour his reputation.

Can NO suppler be trusted these days ?

[Salas]

They don't do it on purpose the real shops. Even USAF got fakes. Its like counterfeit money.

[KatieandDad]

Are the 2SK170s still in production or are our favourite suppliers having to buy from wherever they can get stock ?

I can get supposedly genuine 2SK170GRs.

Must be better than the fakes that I've received.

[KatieandDad]

I've just bought another 16 from a supposedly "GENUINE" stock.

They're not expensive but its just frustrating to be conned.

[KatieandDad]

Salas we seem to have two identical threads here.

Salas hotrodded blue DCB1 build

[Salas]

No, that one was for blue pcbs hotrod builders. You are here bcs you are making it on your own with some twists even, here is the general original thread. There you wouldn't be adding anything directly relevant up.

[KatieandDad]

Well Dalbani have promised to replace the fake 2SK170BLs with "originals". Let's hope these are originals.

I've got some coming from our Oriental friends too.

[KatieandDad]

I'm having a bid of a headache with the delay section.

How much of a delay should this circuit provide ?

For some reason or other the base of my Relay Driver isn't reaching ON for about 10 minutes. If I omit the BC550 I get virtually no delay. I can work around the problem if I could figure out how long the relay should be de-energised for.

The junction of the timing R & C are rising to 12V as I would expect. The issue seems to be the use of the BC550C as a Zener to de-sensitise the relay driver.

I'm not using the BC517 I'm using 2 x BC550Cs connected as a darlington.