Melbourne Daughterboard for M2X

[gary s]

That was quick, Vunce - excellent work, please let us know here when you have it updated again.

 

[Vunce]

Hello All,
The Mouser cart has been updated. (Post# 131)
I replaced R104 and R106 with
Vishay RN55 0.1% resistors. The RN55’s are military precision grade, don’t worry about the 1/10 watt power rating, they are very under-rated.
The 33pF NPO cap has been updated to 100v.
C121 has been updated to a Nichicon KZ because of the backordered Silmic II’s

The backordered KSA1381 might have to be sourced elsewhere, I don’t think that component can be substituted.

Happy Building!!!

 

[gary s]

Thanks again Vunce for the update to the cart.

The KSA1381 is showing for delivery from Mouser end of April.

X - any idea for available alternatives?

 

[poseidonsvoice]

Thanks Vunce! But he already knows the efforts it takes to make such a cart as he double checked my corrections to Andrew Russell's BOM for his KX amplifier design!

Best,
Anand.

 

[xrk971]

Hugh might have a suggestion for it. The 2SA1837 is excellent and handles higher currents and can be used, but flipped around to match the pinouts. There is also a replacement called the TTAxxxx - that Hugh told me about.

 

[gary s]

Digikey have nil stock of the KSA1381 also and they show a back order date towards end of June 2019.

This transistor availability could be a problem now.

Alternatives any one??

 

[gary s]

Maybe the On Semi MJE15035 in TO220 package but also flipped around to match the KSA1381 pin out. Available at Mouser as well.

 

[Vunce]

Hahaha Anand!!
There were a few “typos” in the original

Are you sure you want to sit this one out???
It will be a good one!!

 

[Vunce]

Look what I found!

https://www.arrow.com/en/products/ksa1381estu/on-semiconductor

 

[poseidonsvoice]

Hahaha Anand!!
There were a few “typos” in the original

Are you sure you want to sit this one out???
It will be a good one!!

Well I'll be building this Melbourne Daughterboard since I have the M2X boards, but I am going to watch you fellas enjoy with the Yarra.

Best,
Anand.

 

[gary s]

Vunce, Arrow show these as On Semi, then show 2 different quantities in stock and also then say they are made in China! I wonder if real or fake?

X, the 2SA1837 are listed as zero stock and obsolete at both Mouser and Digikey!!

For this project we do not want to use a transistor already obsolete, and I would be hesitant to use anything made in China, unless big companies like On Semi are now getting components made in China.

 

[Vunce]

I do not think they would be fakes from a large supplier like Arrow Electronics, ON Semi has manufacturing facilities all over the world including China.
Quantities available for shipping are from two locations: 499 from USA,
1796 from Netherlands for a total 2295 pieces.

 

[gary s]

Thanks Vunce, any idea on minimum order qty's and air mail freight cost for non US members from them.

 

[gary s]

I also notice from Arrow that you guys in the USA have free shipping and their price for 100+ is only $0.20 each USD. Just a thought, maybe X could purchase and supply with the PCB's - maybe too late though if he has already started to send out the PCB's.

 

[xrk971]

Arrow is in Netherlands/Germany and they just expressed shipped via FedEx 2-day to me for free. I got 8 SMt IC’s and 4 TO-264 MOSFETs and they came in 3 separate box shipments. Talk about a carbon footprint on these parts from Arrow! I don’t know if it is free to Oz from Germany/Netherlands.

This amp does not use any unobtanium parts. We will find a replacement if you can’t get it from Arrow. Can someone in Oz check please?

 

[Vunce]

Thanks Vunce, any idea on minimum order qty's and air mail freight cost

Check out their website and put a few in your cart and see what the shipping details are to Australia.
I’ve used them several times, the shipping is fast and always FREE!! I don’t know how they do it?

 

[xrk971]

They are in fact, faster than Mouser which takes on average 5-7days and costs $9 shipping.

 

[gary s]

Well, I just signed up and created an account with Arrow, purchased 10 off KSA1381 and got a 12% new member discount with free FedEx freight from the US to Australia.

I have absolutely no idea as to how they do that and make money - all up $3.33 USD order total!!

 

[Vunce]

SWEET!!

 

[xrk971]

They are beating Aliexpress at their own game, but with genuines and FedEx express delivery

There must be FedEx planes leaving with empty or unfulfilled cargo bellies and they go for cheap?