Electronics - Cheap parts. A cautionary tale!

Discussion in 'Amateur Radio News' started by KB7TBT, Dec 1, 2021.

ad: L-HROutlet
ad: l-rl
ad: Left-3
ad: L-Geochron
ad: Left-2
ad: abrind-2
ad: L-MFJ
  1. KB7TBT

    KB7TBT XML Subscriber QRZ Page

    Electronics - Cheap parts. A cautionary tale!

    KM6KPW, VE7JAI, KP4JM and 13 others like this.
  2. K2HAT

    K2HAT QRZ Volunteer Volunteer Moderator Volunteer DX Helper QRZ Page

    ??? Text to read?
    AE0Q, G4HBY, KF7PCL and 3 others like this.
  3. KA1BSZ

    KA1BSZ Ham Member QRZ Page

    yep..you get what you pay for! you buy cheap and get cheap performance.
    KF7PCL likes this.
  4. DO1FER

    DO1FER Ham Member QRZ Page

    Its a fact, that sometimes parts are used which didnt passed the quality control of the producer. Of course these parts are working, but not really well. And they are normaly for the rubbish. That could be the reason for the price. It happend in the past for example with memory chips which were sold at a low price, too.
    KO4CES likes this.
  5. KB1MM

    KB1MM Ham Member QRZ Page

    I used to have a Pro-Sound repair business and the glut of counterfeit parts from the far east was unbelievable. The reputable and well known parts houses were not immune from buying these, most likely unaware. They always made good when it could be proved they were counterfeit (usually sending back suspect parts so they could do a "biopsy" on the suspect parts. It was very frustrating and immensely time consuming to replace sometimes dozens of parts, some quite expensive, only to find a counterfeit part either failed or failed and caused other parts to be destroyed because of the counterfeit part/s.

    One assumes that the parts you order from reputable parts suppliers would be good from the get go.

    There were times that I found myself actually testing each active device, when possible, before installing it but even then, that was not an ironclad guarantee it would work.

    With the difficulty of finding electronic parts these days due to supply chain issues, I can imagine that this problem has been compounded by magnitudes.
    KR3DX likes this.
  6. W3AMT

    W3AMT Ham Member QRZ Page

    I got burned by Amazon once on a part otder. Never again. I will wait longer to get it but at least it not from China!
    KO4CES likes this.
  7. KO4CES

    KO4CES Ham Member QRZ Page

    With regard to "cheap parts" and the industry practice in general, Prolific Technology Inc. has this warning notice for its customers: Please be warned that counterfeit (fake) PL-2303HX (Chip Rev A) USB to Serial Controller ICs using Prolific's trademark logo, brandname, and device drivers, were being sold in the China market. Counterfeit IC products show exactly the same outside chip markings but are generally of poor quality and causes Windows driver compatibility issues. The point is, your concerns are validated ad nauseam.

    With regard to your specific project, I think you're on the correct path by further evaluating the timing of the oscillator to produce a clean square-wave; some digital oscillators continue to use a LC circuit. Anyway, you're brilliant and your presentations are always appreciated.
    KY8D likes this.
  8. KJ7WT

    KJ7WT Subscriber QRZ Page

    Some items: Minor nit-pick, the spikes he sees with the Adafruit board are not harmonics (at least not of the clock board) they appear to be switching noise - their interval looks to be the same as the switching noise he mentioned earlier. Second, I'd be curious to know what kind of inverter he was referring to? is he using a 12vdc to 115 AC inverter, or a switching power supply for his bench? Finally - I worked for a major aftermarket ignition company, and we had some issue with counterfeit power devices (IGBTs and Darlington transistors) from Chinese manufacturing companies. In both cases, we ended up sending THEM devices we bought domestically, because they claimed that they could get nothing else than what they had already sent.
    That being said, I have ordered a number of boards (including the cheap clock boards) from Amazon and eBay (and saved some bucks in the process) and so far, no issues. However if I did have problems, I would send them back - Amazon is very good on returns. A person saying that they will never order from a particular vendor again because of one issue remind me of those who drive a particular brand of car, because, "20 years ago I had a (fill-in-the-blank brand that they will never buy again) and it left me stranded 100 miles from home!" (or whatever). People, and systems, make mistakes, you just have to roll with it, I suppose.
    K8AI, KY8D and KO4CES like this.
  9. KO4CES

    KO4CES Ham Member QRZ Page

    Great point and well received.
  10. DO1FER

    DO1FER Ham Member QRZ Page

    I learned my lesson. So I canceled my accounts at Ebay and Amazon for about a decade. And I didnt regret it until today. Safe stationary and online trade with real people for to communicate with is much better. It avoid those ugly surprises.
    KO4CES likes this.

Share This Page