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NOS Harris IRFP9240s, Vgs matched quads and pairs [The Europe Group Buy]

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Some news about the group buy:
I bought from Rochester:
Harris IRFP9240 = 100 parts
Harris IRFP9241 = 34 parts (the whole remaining stock)

and from Tedss, Harris IRFP9140 = 60 parts (the whole remaining stock)
also for my own usage Harris IRFP240R = only 16 parts (the whole remaining stock)

I will update you on the price as soon as custom is cleared and I have visibility on the tax and all.

The IRFP9241 will allow for a few cheaper matched pair (only difference with 9240 is a slightly lower Voltage rating)

600 bucks spent.... hope these are genuine....
 
Quick update, I am still waiting for the parts from Rochester (glad I paid 28$ for "Express" shipping...)

Here is what I am planning to do once I receive them:

1. I will measure the parts at room temperature and make a first sorting of the parts on Vgs.

2. Once this is done I will place the parts by batch on a large heatsink with big thermal inertia in a oven at ~50deg Celcius and measure them again. This will allow to see the effect of temperature on curves and I will then either confirm or revise the matching.

The goal is to see whether temperature elevation changes the sorting of parts
The reason I will breakup the parts by batch is I cannot garantee temperature precision and thermal stability on the long term, so I can only trust parts which are next to each other on the heatsink, and measured within a small time interval.
 
Update today... after asking me to verify my name and address (13th Nov) which I had already provided during the order (7th Nov), now Rochester is asking for my website (20th Nov).
Why does it matter ??? Seriously, 2 weeks to process my order???

I guess they still have not shipped the parts.
 
People in this forum do not understand the cost of business for entertaining DIY customers who make maybe one 250USD purchase in 5 years.
Do you know how much the administrative work costs to deal with one such small order ?

There maybe small companies eager and fit to do those small retails.
But not company like Rochester.


Patrick
 
My order was double that amount. I was way above the MOQ, and even helped them clear some of their stock.
Should I apologize for my business ? Lol

The payment part did not seem to be of much trouble ;)
If they don’t want to deal with “small” orders, they’d better be clear about it from the start, and not have a web front end that pretends they’re just like any retailer.

I work for a very large business, a LOT larger than Rochester, so I know exactly what it means to process this type of order. Usually for this kind of business, they are their own enemy when it comes to cost of processing orders (rigid and inefficient IT, etc). They put their own barriers.

....Bottom line, I do not feel sorry for them.
 
Good news! I finally received the parts :)

Made a first batch measurement and labeled the parts.
 

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By first measurement batch, I mean I measured all 100 parts at room Temperature to make groups.

The result looks pretty nice to me. Some may stop here and sort the parts on Vgs.

I intend to go a bit further and check how curves move with a bit of temperature.
 

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For your reference, here is what temperature does to curves.

All curves measured on the same part at different time intervals while cooling
Upper curve (pink) is measured at ~60 deg C, while bottom curve is at room Temperature (22 deg C)
 

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A little bit off topic observation:
Below is an illustration of what some have said (among which Nelson Pass I think) that parts from a given tube measure relatively close to each other

These are the very last 34 remaining stock of Harris IRFP9241 from Rochester, delivered in 2 tubes.
It is very clear that the first tube contains leftovers from different batches (matching reject ?) while the 2nd tube is from the same manufacturing batch, very close measurements.
 

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