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  1. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    A huge thankyou to Hevans ---you are a true soldier! Your superb advice will be truly appreciated -- apologies for my primitive approach /backwoods ideas -- but the house breaking burglaries prompted me to make a whole lot of battery chargers for my DIY--alarms I have installed in a dozen...
  2. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    You are a superstar --Audioguru ---a magician ! so very grateful ----appreciate ( I Successfully -------sorted out that TIP circuit horror) last night --all night --replaced the 122 with TIP 41 C NPN specs data say its close to 122- took a chance --trial &error --- connected the pins as per...
  3. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    I think I am not going to get a schematic or circuit here --using that rectifier bridge modem ----- and all its controlling components --to give a reliable 13 .6 volt -one amp charging output- Have searched the web exhaustively--- for such a circuit --must be wishful thinking--but will keep...
  4. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Thankyou so much hevans ------ wow !---simply a man I can really admire --straight from the school of "if at first --failure -try again &again & again I am a wildlife painter /taxidermist /bowhunter /guitarist /musician /guitar builder /wood turner - (born 1949 ) Simply crazy about electronics...
  5. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Steve --here are macro fotos I took -- of how I have interpreted your method of testing Zeners--- probably not too good -- 1Used 12 VOLT m/cycle battery connected 2 zeners I assume are the real Mc Coy --- One is marked 12 ( volts?---the other 6 ) used a 22 k resistor --in series with each...
  6. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Many Thanks Steve --- will keep trying to figure out reverse & forward bias --!everyone of a hundred diodes I have removed painfully from old PC boards ----- tested using a SINGLE 12 VOLT m/cycle lead acid battery --brand new --- 10 k ohm in series with the Zener "lookalikes' All seem to give...
  7. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Wow ---thankyou Hevans 1944---! Really appreciate all the trouble you have gone to ---to teach me important facts about Zeners----- I am learning this complex field stubbornly --not all of us are gifted geniuses I love circuits --been building them 4 - circa 25 yrs ---albeit direct from...
  8. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    ok ---- ok------Thanks again Audioguru That TIP 122 /zener set up --as you say -is-possibly-- a 3rd world (probably Swagatam nightmare) I tried one of his ("simple FM radio circuits ---few years ago) It even baffled a PH d ---expert on this forum ---he concluded same as--you have--...
  9. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Thankyou so much for all this info Hevans ! I still cannot IDENTIFY a one watt Zener 12 volt --! Your lesson on its function /characteristics etc is way too complex - but I do understand a bit here & there --"reverse breakdown voltage & forward operating region I will never grasp ---way too...
  10. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Audioguru ---- you were right on ---I messed up big time ! How I could connect the middle pin (collecter ) to the Zener --is plain blind stupidity --forgot completely how I made audio amps from this TIP122-many years ago !( without a problem ) So I had to reconfigure the connections ----I got...
  11. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    OK ---Thankyou Audioguru --- if I connected the TIP incorrectly -- can you show me how to connect another TIP 122 ( I have many spares) I have found a fat one watt zener glass diode ---but not sure what voltage --reads 12 v one way --4-5 voltsv the other way --- is this 7 or 8 volt Zener ? I am...
  12. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    So now I am again in the dark --- if forward volts are 5.6 --reverse voltage is what/?12 VOLTS ? AND how come I connected the TIP leg pins wrong ? I followed the schematic exactly as it was shown --- middle leg to zener ----- left leg receives volts from rectifier diode bridge -- right leg is...
  13. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Sincere apologies Steve --I meant one watt ----you said bit bigger --- OK voila !! searching carefully ---I found 2 slightly broader in girth ---glass diodes with odd markings - (see fotos) Astounded! when tested your method --- they show TWO voltages --one way -then the other --precisely as...
  14. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    WOW ---Audioguru ---- you certainly got the EXACT TIP 122 circuit I have made! --What I did --to get 13 .4 volts -----output --- was 1 --replace the ZENER DIODE on middle leg of TIP transistor with large rectifier black diode ( IN 4007 or similar ) 2 ----removed the LED ---& I K ohm...
  15. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    wow !! ---those 2 X9V BATTERIES ---10 K RESISTOR idea /method is a killer !! works SUPERBLY -- GOT 4 .5 VOLTS ON ONE glass diode ( tiny ) 5 .8 volts -7 volts on others --some read 2 -3 volts only ! proves some are Zeners ---the others I knowq are IN 4007 and 4001 STD rectifier diodes not...
  16. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

  17. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Many Thanks Steve--- will attempt your 2x 9v battery idea -- what diode do I use --if I am not sure what a Zener even looks like ? and most important of all ---how do I determine the WATTAGE range ? The battery charger circuit shows a ONE WATT 12 VOLT zENER -IS required ! on the middle leg of...
  18. Z

    HOW TO ID-- A 12 VOLT ZENER DIODE --ONE WATT --

    Hi ---- The same old problem -revisited ----trying to find identify a Zener diode from hundreds of look-alikes dead ringers -- A battery charger circuit ----using TIP 122 power transistor --- requires a rugged Zener diode voltage regulator ----- --tried a tiny glass orange diode (cannibalised...
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