Hi, I need some advice on what transistors you guys would advise for the input stage of an amp running +-45V DC rails.
Also need giudance on a good selection for the smaller transistor to pair with the C3503 VAS transistor.
Im kinda limited to RS components, and dont want to order 100s of transistors.
Any help would be great.
Was using 2n5551 and 2n5401, dont have any left.
Also need giudance on a good selection for the smaller transistor to pair with the C3503 VAS transistor.
Im kinda limited to RS components, and dont want to order 100s of transistors.
Any help would be great.
Was using 2n5551 and 2n5401, dont have any left.
It would help if you posted the schematic .
"input stage of an amp running +/- 45 DC " is too general as is "VAS transistor " .
If you are designing it you could at least post a penned drawing of what you want to achieve .
"input stage of an amp running +/- 45 DC " is too general as is "VAS transistor " .
If you are designing it you could at least post a penned drawing of what you want to achieve .
Have you looked at MPSA42/92 or ksa1845/992? to replace the 2N5551/5401?
You might look at mje340/350 to use with the 3503/1381?
These are only my suggestions, YMMV
You might look at mje340/350 to use with the 3503/1381?
These are only my suggestions, YMMV
I've used the ksc1845's before. I have a ton. Vceo is 120 so should be fine. Not sure if RS stocks them, I tend to go DigiKey.
There doesn't appear to be much chance of RS Components supplying KSC1845/KSA992 in South Africa though. They show them as stock items with minimum quantity of 200ea. and a lead time of 12-24 months + delivery time to SA!
That is one unenthusiastic sales pitch - 'seems like they just don't want to supply 'em and you need to open an account with someone who is and also holds stock, like Mouser or Digi-key.
That is one unenthusiastic sales pitch - 'seems like they just don't want to supply 'em and you need to open an account with someone who is and also holds stock, like Mouser or Digi-key.
Digi key is currently out of stock. Happened to me last year. I am wondering if it is going end of life. I picked up a 2K lot last time so I am good for life. They are only a nickel in large quantities.
Looks like I'll have to go Digikey. Since RS have offices in south africa, there are no delivery charges.
I'll have to see what shipping from Digikey Mouser is to South africa
I'll have to see what shipping from Digikey Mouser is to South africa
Sorry I don't understand RS Components South Africa as well as I should. It appears to me that they do have the Zetex PNP/NPN pair 558/696B in stock, if I interpret the green box correctly
PNP sales page
NPN sales page
These are 400V (PNP) , 180V (NPN) rated transistors. I used them in the "Dreadnought" front end of the VFET DIY amp sold through the diyAudio Store, and I'm very happy with them.
Other Zetex devices to consider: ZTX457 , ZTX458, ZTX857 (NPN)
ZTX795A, ZTX957 , ZTX958 (PNP)
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PNP sales page
NPN sales page
These are 400V (PNP) , 180V (NPN) rated transistors. I used them in the "Dreadnought" front end of the VFET DIY amp sold through the diyAudio Store, and I'm very happy with them.
Other Zetex devices to consider: ZTX457 , ZTX458, ZTX857 (NPN)
ZTX795A, ZTX957 , ZTX958 (PNP)
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Attachments
Vostro, I have ordered four Sankens from Digikey a month ago. The parts were R150 ($11) and shipping was R600 ($44). Try TRX electronics, they are local and source their parts from Mouser at very good prices.😉
Shipping is a killer. Years ago I made an order from Mouser. I was shocked that above the shipping fee, customs decided to charge me close to R1000.
The reason I didn't attach the circuit, is because its just the standard blameless we all have seen here a million times.
I made a couple of these boards as part of me learning kicad. Sounds good though.
Attachments
Interesting, after your reply the other day I bought a few hundred ztx558 and 560, as well as 458, not to mention about 1000 bc557c/547c.
After that, I ran out of ideas! (Once upon a time a I had a small stash of thr Zetex versions of BC107c which were very good, I wish I had saved those!
As you are duplicating Self's Blameless design, perhaps you are aware that when faced with the same availability problem some years ago, he simply altered the small signal semis (all of them) to MPSA42/92 types. It's evidently non-critical to his design and test purposes, as long as the source is original On-semi and not cheapo copies.
Try sourcing from their North American offices, much cheaper than European offices of the same seller.
And ask for a Fedex standard box full for shipments, cheapest to India.
It is cheaper for my client to get avalanche diodes from Mouser USA than buy locally...from Mouser India.
Check with their competitors like element14 and others too.
RS is not so strong in North America I think, and they tend to be expensive.
And ask for a Fedex standard box full for shipments, cheapest to India.
It is cheaper for my client to get avalanche diodes from Mouser USA than buy locally...from Mouser India.
Check with their competitors like element14 and others too.
RS is not so strong in North America I think, and they tend to be expensive.
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