Pioneer SX-9000 2SD218 output substitute?

[Akoustic]

Any one know of a substitute output transistor (2SD281) for the SX-9000?

TIA
Dwight

 

[markthefixer]

The 2sd218 is a NPN TO-3 silicon transistor, with a 100v rating, 7 amp collector current and 60 watt power dissapation.

Most modern replacements will be significantly faster, higher frequency devices that could be unstable.

but I would take a chance on:

863-MJ21194G npn to-3 250v 16A 250W 4mhz 8-75hfe $4.10

I would do at the least BOTH on the channel, if not both channels.

I would also get # 534-4662 to-3 mica insulators $0.16 each at the same time, it's cheap insurance, and # 532-249 1 oz thermal compound $4.71 at the same time... the old stuffs probably long dried out...

these are mouser stock numbers and recent prices.


edit: well, I'll be.... 4000 posts.........

 

[tri-comp]

4000+ even !!! :tresbon:

Go here for a Bipolar Transistor Cross-ref guide to be taken more seriously than most.
http://www.on4rcc.org/equivalences.pdf
Mainly because it's been compiled by SGS-Thomson and not by some 3rd party know-nothing know-it-all.
Still, in this case I wonder. They recommend a TO-3 type BUV50 but upon downloading the spec's on that it looks like a switching transistor and not like something developed for audio. Could be OK, though.

rgds,

/tri-comp

 

[Akoustic]

markthefixer, thank you tremendously for your quick, helpful and thorough response. Just what I needed. Mouser thanks you as well.

tri-comp thank you tremendously as well for the cross reference PDF. Ordered the 863-MJ21194G but now have specs sheet for all 3 transistors discussed so perhaps I can learn a little about specs and substitutions.

btw, this is my 1st vintage pioneer. My existing gear is mainly sansui so looking forward to hearing this exceptionally nice looking receiver.

Thanks again and once all parts are in and I dive into repair, I will take pics and start a new thread.

Dwight

 

[Akoustic]

Thought best to stay on this thread as others will be able to reference the substitute transistors and their performance. Here is quick update. Received the output parts last week but did not start work on the SX-9000 yet. Appears the entire heat sink with the main amp board must be removed to work on it. This will involve unsoldering wires for removal. (Had to get solder gun for this step). It became apparent pictures were a must. Even with my poor camera work I noticed a cooked resister (R26 220) on main amp board. To coin a phrase from Echowars, it will be a "Pita" to work on. I then decided it was best to create a list and order new resistors and transistors for the entire board.

Will definitely need parts on hand before dismantling starts. It appears my Sansui stash of extra ordered resistors and fuses will be of no help with this board. Thanks to post by Stene I will substitute the 2SC458 with 2SC2240. (partsexpress $0.68 EA (5 + ))

Do need substitution help for the 2SA485 and the 2SC870 please.

Thanks again in advance.
Dwight

 

[Nicowico]

Any one know of a substitute output transistor (2SD281) for the SX-9000?

TIA
Dwight

You have mail.