Transistor needed

[AlexC]

Has anyone got a BC640 PNP transistor? I have a problem with a JR DSX9 transmitter that drains the battery even when switched off.

Thanks

Alex.

[Mike_K]

I think BC640 are only a few pence from sources like RS, Farnell, Rapid Electronics etc, have a look at one of those

[Pchristy]

https://www.ebay.co.uk/itm/272237879924 ... v8QAvD_BwE

It appears to be a generic bipolar PNP transistor. Max current rating is 1A, and max voltage 80V, but I suspect not both at the same time!

Do you know what its function is in the circuit? You might well find that any generic silicon PNP will do if its just being used for switching.

--
Pete

[Tobe]

Concerning the voltage regulator it has been a long story and there has been several service bulletins depending on the version.
https://www.modelflying.co.uk/service-annoucement-made/
Also to be notice is that LiPo's is a no-no as they use a linear voltage regulator, which converts excess voltage to heat. So higher input voltage, more heat and as there is no moving air inside the Tx.....

[Dave]

When my washing machine stopped in the middle of a cycle the problem turned out to be a stand-by power supply chip with a crater blown out of its top.
Farnell listed it at 85p + Vat. Postage under £20 was £9.99 iirc!

Ebay threw up 3 for a fiver. Not too silly as the first fit might have gone pop too.

I think it was Phil-G who recommended bitsboxuk.com . First Class postage is £2.20 BC640 50p each.

[AlexC]

Dave, I ordered a few from bitsbox.

Thanks for the info.