User Error. Its Always User Error.

Discussion in 'Homebrew and Kit Projects' started by VK4HAT, Jun 20, 2018.

ad: L-HROutlet
ad: l-rl
ad: Left-2
ad: L-MFJ
ad: Subscribe
ad: Left-3
ad: MessiPaoloni-1
  1. VK4HAT

    VK4HAT XML Subscriber QRZ Page


    Sorry, the picture is upside down and all the electrons are going to fall out. ;) Anyway, i started building a new receiver project and just for giggles decided to start in the middle and work my way out from there. So i am building the IF strip. Starting with the first IF amp I put it together and put power on it and nothing. Checked to make sure its wired right, it is, check all component values they are correct, checked the orientation of the transistor and its in the right way. So I walked away and left it sitting on the bench after doing my head in for a few hours.

    So tonight i take another look at it and think, well i will pull out every component and check it on the component tester. Being colour blind this is the only way I can tell if a resistor is the right value or not. So i rip out the emitter resistor and its 15o. K not R. Change that and everything works. Its always the idiot on the end of the soldering iron that is the problem. Nothing more. Anyway, now i can go back to doing what I was going to be doing in the beginning, measuring some impedance's without the 4:1 transformer there so i know what I am dealing with when i match it up to the xtl filter.
    N1OOQ likes this.
  2. VE3CGA

    VE3CGA XML Subscriber QRZ Page

    sorry but I had some smiles after reading this.
    reminds me of some of the early days building with tubes.
    One of my friends came over with a 60W tx he had just finished and wanted me to check it out.
    Should have been my first indicator of trouble. I did a quick checkout then decided to plug it in and see.
    As things were warming up my mother being thoughtfull brought a plate of oven fresh cookies down to us
    she almost made it into the workshop when a large cap blew. no explosion but quite a lot of noxious steam complete with a loud whoosh
    she just turned and walked back upstairs. My friend and I had to evacuate and as we left I hit the "E-stop" switch
    later we found the 100uf 450v cap was in backwards
    N5WVR and VK4HAT like this.
  3. N0TZU

    N0TZU Platinum Subscriber Platinum Subscriber QRZ Page

  4. WA9SVD

    WA9SVD Ham Member QRZ Page

    If you are color blind, don't apply to be in the bomb squad...
    K0OKS likes this.
  5. WB8NQW

    WB8NQW Ham Member QRZ Page

    When I was a student at DeVry, (1960), a fellow student had built a kit from Heath that did not work and asked me if I would look at it. When I looked at the underside of the chassis, it was a horrible mess with mid-air connections on resistor and capacitor leads and solder used as wires. I asked him what happened. He assembled it following the book. When it did not work, he figured that he had made a mistake so he dis-assembled it and rebuilt it using the same parts but now re-arranged. Very few of the component leads were long enough so he spliced wires or solder on them. When he ran out of wire he used solder for wires. I tried to politely hand it back to him and wish him good luck.

    VK4HAT likes this.
  6. KL7AJ

    KL7AJ Ham Member QRZ Page

    Seems to be a short circuit between the keyboard and the chair. :)
  7. VE3CGA

    VE3CGA XML Subscriber QRZ Page

    Bob WB8NQW, we must have run into the same fellow. ha ha. just before I figured out ham radio was real, some friends and I were playing around with some circuits we found in an old library book called the arrl handbook. Anyway I got my rx to barely receive a couple stations, (keep in mind these were built from old tv sets) another friend wanted me to look at his radio. Same deal wires all over, spliced with anything conductive. Its great to look back on early experiments. Different era's had different things of danger for kids to play with. My uncle tells a story of just walking down the street when there was an explosion at a friends house. he looked over just in time to see his friend running out of the house after blowing out the front window while doing his chemistry set.
    I sure did some stuff that should have been on funniest home videos, wonder what todays kid can do with an Ipod

    73's BOb VE3CGA
    N5DMC likes this.
  8. VK4HAT

    VK4HAT XML Subscriber QRZ Page

    So tonight i make a little more progress on the receiver. But, even I can manage to out do my own stupidity. So i have been sitting here for the last hour wondering why my 500hz CW filter is AM Wide? Then i dawned on me, 470 capacitors are not 470pf, they are 47pf. I am orders of magnitude out again. Oh well, this one is an easy fix.

    N5DMC and N0TZU like this.
  9. KD9KSO

    KD9KSO Ham Member QRZ Page

    They weeded out the color blind before attending ICBM maintenance school in the Air Force.
    VE3CGA, VK4HAT and KD2ACO like this.
  10. AA7QQ

    AA7QQ Ham Member QRZ Page

    My Dad was a sonar tech on the George Washington (SSBN598). He was color blind. That's why the wires are numbered.


Share This Page