buyingfilterRF
A RF receiver project I'm working on calls for a very specific SAW bandpass filter. I've checked all the usual sources here in the US (Jameco, Mouser, Digikey, Newark, etc) without success. What I'm finding is that the part I'm looking for is highly specialized and thus difficult to find anyone that sells them in low, hobbyist quantities.
What are some approaches for buying difficult-to-find parts in low quantities?
If you're thinking about ISO-9000 that's about the quality of your organization and its processes, not your products. You can have ISO-9000 certification and still produce the worst crap.
There are certification organizations, like Underwriters Laboratories in the US and TüV (Technischer Überwachungsverein) in Germany. Many components won't have certification, though. You'll find it mostly in safety sensitive components, like where isolation from mains is important.
Other organizations, like IEC (International Electrotechnical Committee) write specifications, but don't certify.
A good manufacturer should hand you its own testing procedures for its components upon request, as well as test reports. Those are sometimes included in datasheets.
Some will refer to certification organization standards, like shown in this snapshot of a random Littelfuse datasheet:
Note that the Underwiters Laboratories (the top logo) and PSE (Product Safety Engineering) logos refer to their respective certification, while the CE logo doesn't imply this. (The CE logo means that you claim to comply with CE standards).
Wire-wrap wire is 30AWG (about 0.25 mm). It is commonly used for this sort of thing and is available at many electronics suppliers.
Best Answer
Go to the manufacturer's website, find their list of franchised distributors and talk to them. However don't be surprised if you have to buy a whole reel/tube/tray and wait a few weeks, but you might be lucky and find someone with stock. You may be able to get small qtys as samples from the manufacturer or distributors. However there are many parts that you just can't buy in small quantities.