They arrived today.
Physically:
In close examination under illuminated magnification they look close enough to mine for printed characters but not exactly the same. Mine have somewhat finer & fainter print. Also the plastics mating line across the top has a brow to the right on yours but bit longer and to the left in mine. From the back mine look somewhat bulkier for the plastic head with a bit larger molded dot also. No character in the dot as in yours. Legs length and metal finish are very near.
Electrically:
hFE is very close between your two samples (173-175). Their Ice/Vce curves are matching. Nice flat curves with even spacing. Plotting like some good type but low hFE transistors. Totally faked or original low hFE reject wafer you will probably never know. In any case they don't fit the Renesas datasheet E grade (not even the D grade for that matter). They are far apart with my 2545E in hFE when tested under exactly the same conditions.
Attachments
Thank you for the information Salas!
So they are definitely not authentic 2SA2547E. My conclusion is: The 2SA2547E is no longer available anywhere. I will contact Dalbani with these findings, and see how they respond.
Interesting though, that they seem to be decent enough devices, whatever model they are really are. If I can't get a refund, perhaps I will try using them..
So what seems to be the best alternative? BC550c? (Fairchild or CDIL?), ksc1845?...
So they are definitely not authentic 2SA2547E. My conclusion is: The 2SA2547E is no longer available anywhere. I will contact Dalbani with these findings, and see how they respond.
Interesting though, that they seem to be decent enough devices, whatever model they are really are. If I can't get a refund, perhaps I will try using them..
So what seems to be the best alternative? BC550c? (Fairchild or CDIL?), ksc1845?...
BC550 is around 150 Ohm Rbb'. I also have some Toshiba 2SC1815-GR that they measure near hFE 300 by majority, they got ECB pins order too like the 2547, 50 Ohm Rbb' 2pF Cob 1dB NF and very linear curves. I don't know what is the characteristics priority in this circuit, but if the author says they are acceptable too, this is how originals should look like, save batch code differences of course
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This one is alike if not better http://www.ebay.com/itm/10x-2SC2240...408680?hash=item5d3273cde8:g:HqoAAOSwQJhUiS3O
and now I'm curious about that
Hi,
everyone that wants a boards, please simply send me a message!
Price of the new board is 11 Euros, together with shipping & paypal it comes to 20.07 Euros.
@Stuey: the BOM is included in the documentation that comes with the board, but you can find it also at LinearAudio:
http://linearaudionet.solide-ict.nl/sites/linearaudio.net/files/ha v6 building notes(1).pdf
I've not yet been able to add the BOM to the wiki, sorry for that!
everyone that wants a boards, please simply send me a message!
Price of the new board is 11 Euros, together with shipping & paypal it comes to 20.07 Euros.
@Stuey: the BOM is included in the documentation that comes with the board, but you can find it also at LinearAudio:
http://linearaudionet.solide-ict.nl/sites/linearaudio.net/files/ha v6 building notes(1).pdf
I've not yet been able to add the BOM to the wiki, sorry for that!
high precision RIAA-caps
As always, getting the RIAA caps as high precision, high quality types is difficult.
If someone needs all required RIAA caps as super-duper 1% precision Polystyrene types as I used originally (LCR FSCEX), I can offer a full set with all 6x RIAA caps (for stereo) for 20 Euros. Yes these do not come cheap!
As always, getting the RIAA caps as high precision, high quality types is difficult.
If someone needs all required RIAA caps as super-duper 1% precision Polystyrene types as I used originally (LCR FSCEX), I can offer a full set with all 6x RIAA caps (for stereo) for 20 Euros. Yes these do not come cheap!