Waiting for Godot...er, parts

[Enzo]

You need parts, you order them, they come.

Except when they don't. Back orders are a fact of life. Customers don't always understand them.

A while back I mentioned a small TO92 MOSFET in a Marshall Haze. TN2404, I need one. And I need the TN2404KL, the TO92 version. I looked up the parts list in Marshall/Korg - no listing.
Allied - not a stocked item
Digikey - not listed
Newark - none in stock
Mouser - none in stock.

Now Newark says none in stock, but they will "direct ship from Farnell" in the UK. There is a $20 charge for this, and a 41 day lead time

Mouser, always there for me, shows zero in stock but status "on order." Expected delivery date for 1900 of them is 8/26/10.

SO I don;t have many options for getting this part. At least not from my regular suppliers, and without spending hours on an Easter Egg hunt. SO way back when I needed this, I ordered it from Mouser as part of a larger order, leaving them on back order status. That status is reflected in my invoicing and packing slips.

Meanwhile the customer calls every few days wanting to know if I have his amp fixed. No, I am waiting for your part that is on back order, sorry. And then the standard conversation about how he needs the amp, etc. And I am thinking, yes, and I don;t get paid until it gets fixed either.

The customer has run out of patience, and calls me, "Can I just come pick up my amp? I want to take it somewhere else." Yes, of course you may.

So, the amp was diagnosed, and parts ordered. None of my suppliers could provide the part and back order occurs. Parts to ship 8/26/10. Customer declares he wants to take back amp 8/26/10. Customer will find some other repair shop, and they will find they need the TN2404KL. They will look it up in Mouser, and find 1900 of them in stock, because the back orders just filled. They will order the part and have it in a few days and fix the amp. He'll be the hero, and the customer will tell all his friends that Enzo doesn't know what he is doing. And he wil never understand why that other guy could get the part and I couldn;t.


Maybe I ought to go sell ladies shoes.

[Mark Black]

I can see it now:

"Sorry ma'am, we don't have that style in your size right now, but we should be getting more in a week or so..."

On a more serious note - I have been noticing that Mouser seems to have more parts on backorder lately. Or maybe I'm just needing weirder parts lately.

I had to do the Newark/Farnell direct-ship-from-UK-no-return bit recently for some AVX/Elco SIP ribbon cable connectors that seem to have no other available substitute to finish up a Soundcraft Series Two console. Other than the extra expense of the $20 surcharge that went pretty smoothly and delivery time was really fast.

[Techknowman]

1. With the downturn in th economy all venders are looking hard at having large inventorys of parts.
2. As venders they have to order/buy large quantitys to get them at all, which leads back to Item1.

But i agree. I have a story about a givin optocouple we used in our fire gate systems.
It was a very common 4 circute darlington output AC input opto. We incorporated it in our design. (we use 60 per unit and have built to date 40 units)
A year into our production they obsolete the part. Ok we will just use 4 of the singles or 2 of the doubles. Obsoleted as well. We get 50 here 100 there and make production just in time.
So I redesign the PCB's to accept a new SMD 4ch part, even though its current handeling capacity is slightly less, it will work and is common with other venders so subs should be no problem.
Ordered parts, used them up, go to order more and the world is out of stock! Nobody has them, we can't even get them from the OEM any quicker than Mouser. no one has the subs ether. So getting parts can be a real pain.

[jrfrond]

I just had that situation a little while ago today with an Ashdown amp, and the client is SIR! The 4700/100 radial snap-in cap I have in stock is the wrong size and wrong terminal spacing (AND 4 pins). Sooo.....I look up the proper cap value and size (30 x 50mm) in Digi-Key. Three different manufacturers, but none in stock. Closest lead time was Feb. 2011 (!). Mouser doesn't even have it listed. Allied only has 35mm dia. (won't fit), and no stock at Newark either.

So there ya go! To make a long story short, I found the cap we needed in Crown stock (uninventoried, which further pissed me off!), but that was IT!!! Must be the last cap of this size anyone had in stock anywhere near the East Coast!!!

It's true, both manufacturers and suppliers alike are B/O on lots of items nowadays. It's all part of lean business operations, but it sucks when you need it.

[Enzo]

I recently went to order some MJ15024, a couple months ago maybe, and found even them on b/o all over the place. I even called PV for some of their house numbered ones, and they were out. Everyone got restocked soon enough, but there I was with only two in a drawer, no one had any, and a PV1.3k needing a boatload of them.

[jrfrond]

I recently went to order some MJ15024, a couple months ago maybe, and found even them on b/o all over the place. I even called PV for some of their house numbered ones, and they were out. Everyone got restocked soon enough, but there I was with only two in a drawer, no one had any, and a PV1.3k needing a boatload of them.

Next time you are in an ordering bind with these, sub the ubiquitous MJ15024/25 with MJ21193/94. Identical 250V/16A/TO-3 specs. I haven't delved deeper into the specs to find out where the difference is, and perhaps I should. I just know they work. I wouldn't have found these, except that I assumed small quantities of these from another defunct shop whose parts stock we purchased, and I had to spec all of the semi's for our parts database.

[Techknowman]

Sellers in China selling on Ebay always seem to have them!
I'm always a bit scared of buying them due to all the fakes. lots of renumbering going on from what I've read.

[Enzo]

Some folks do, but I never ever buy parts on ebay. I only buy from real suppliers.

John, I am aware of those other types. I should look into them as well, but my only fear is mixing them with the 15024 series. If they are made on a different process they may not track with the others. If it were a matter of changing a whole row of one to the other, then no problem, but I am not ready to mix them.

I never stocked the 21194s, as they sem to be the same thing as the MJ15024, and why duplicate. And sicne my main applications are often things like the PV that are already stuffed with the MJ15xxx, I lean that way.