SA3A: 2N5089 and 2N3417 substitue or real deal / transformer choice

[atticmike]

Howdy fellas,

Been desperately looking for 2N5089 and 2N3417 from the official bom for the SA3A. They're out of stock at mouser and marked obsolete. What can I do?

Also, which trannies do you prefer? I got a pair of original 1978 input trannies but where should I get the output and autoformer from?

Ed anderson vs those:

http://www.ebay.com/itm/New-Replacement-T4-B11184-Autoformer-UREI-UA-LA-3A-UF-/221244694874?pt=US_Vintage_Pro_Audio_Equipment&hash=item338336215a

http://www.ebay.com/itm/UREI-B11148-Output-Transformer-all-LA-3A-1176LN-Rev-F-UI-/321148745153?pt=US_Pro_Audio_Parts_Accessories&hash=item4ac5f4f5c1

About the T4B, is it better to get the original or Kenetek? Got a fellow GDIY member offering me the original.

Mike

 

[Dylan W]

Quick google turned up these. Futurelec also often has hard to find semiconductors.

http://www.mouser.com/ProductDetail/Central-Semiconductor/2N3417/?qs=ljbEvF4DwONGVG9pzzzvUA==
http://www.mouser.com/ProductDetail/Central-Semiconductor/2N5089/?qs=Ypxpq5eNvNX4czmw0zy01w==

 

[atticmike]

Quick google turned up these. Futurelec also often has hard to find semiconductors.

http://www.mouser.com/ProductDetail/Central-Semiconductor/2N3417/?qs=ljbEvF4DwONGVG9pzzzvUA==
http://www.mouser.com/ProductDetail/Central-Semiconductor/2N5089/?qs=Ypxpq5eNvNX4czmw0zy01w==

Will they do? There's a discrepancy between the Continuous Collector Current: 0.5 vs 0.45 A (BOM vs Substitute). The 2n5089 is worse, 0.1 vs 0.05 A.

 

[mhuss]

That class of transistors are rarely or never run at or near max current/power. The important specs to look at are probably current gain (aka beta) and noise.

--mark