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  1. globecollector

    Looking for Datasheet on old Texas Instruments strobed Digital Clock Chip, M35020

    Unfortunately I turfed most on my data books when I moved to a smaller house. I had a mate with a big workshop in the basement of the Chemistry Department at the University of Tasmania, he was the last tech standing and had gone from working on N.M.R. machines to fixing photocopiers. He recently...
  2. globecollector

    Looking for Datasheet on old Texas Instruments strobed Digital Clock Chip, M35020

    Problem solved! The The MK50375 is a really logical and simple to use chip. It can drive V.F.D. displays or Seven Segment L.E.D. There is no crystal reference oscillator, phase locked loops or strobing guf. It simply takes the 50Hz (square wave) in on pin 30 via a 1N4148 with the cathode facing...
  3. globecollector

    Looking for Datasheet on old Texas Instruments strobed Digital Clock Chip, M35020

    Further Developments, found another digital clock similar, this one has the non-strobed MK50375N clock chip in it, again, Mr. Google seems to have "forgotten" this one too....any success finding those databooks?
  4. globecollector

    Looking for Datasheet on old Texas Instruments strobed Digital Clock Chip, M35020

    Thanks, it would be appreciated. I chucked most of my data books when I moved house. Kept just NS Linear a Philips HEF4000 Logic and Motorola Linear book. Ironically these seem to be the easiest to find online...but who ever made such a rational decision under the pressures of a house move...
  5. globecollector

    Looking for Datasheet on old Texas Instruments strobed Digital Clock Chip, M35020

    I have a digital clock, (taken from a space heater) which is built around the T.I. M35020 clock chip which has strobed display and buttons...in this application it also takes in basic data from an LM339 from thermistors and outputs data to control relays and TRIACS for the heater...none of which...
  6. globecollector

    Tin plating

    He's using a Graham Condenser (Coil on the inside). The crap is probably Iron Compounds, Calcium Compounds and Fluorides...would not do that two neck flask much good! It is annoying he does not narrate the video and does not give the azeotropic boiling point of the HCl-Water mix...
  7. globecollector

    Tin plating

    Purple before H2O2 and orange after...if it were inorganic I'd say Chromium-III to Chromium-Vl. You need to purify that HCl to get all the "mystries" out of it. Sounds like you need a distillation apparatus....add a lot of salt to the HCl put it in a flask, heat the dayloghts out of it to...
  8. globecollector

    Tin plating

    Cupric Chloride (Emerald Green) is a product of the normal Ferric Chloride etching process. It will attack copper metal in an anaerobic environment forming insoluble cuprous (Copper-I) Chlorode, but again, this gugs up the surface and slows further attack in the absence of any ligand forming...
  9. globecollector

    Tin plating

    It speaks pretty clearly to me....the redox potentials of the free ions are given at 1.57 and again at 3.04 and the flipped redox potentials for the complex ions at 3.27. Visually you can see the reduction of tin onto the copper at 2.45 and the reaction is really rapid so the copper need only be...
  10. globecollector

    Oscilloscope advice.

    One really cheap way to monitor the output of a rotary encoder would be to pad the output of the encoder down and feed it into an audio amplifier (and just listen to the tone produced). if it is above the audible range a "T" Flip flop would divide it by two.....or use sound card of a PC running...
  11. globecollector

    Large motor start up

    Go back to the PWM driver you had functioning on 60v and "work forward" and redesign the output stage for 72v. That way you start with 95% of the circuit and just modify what has already proven itself. Make sure the MOSFET(S) have sufficient Vds and have appropriate snubbers across them. Also...
  12. globecollector

    Tin plating

    Been done already on You Tube by a really skilled chemist in Canada....he uses thiourea as a ligand to redox tip the tin-copper couple...
  13. globecollector

    Fast Switching Relay for High frequency Signals

    Interesting hybrid device (MP108)...I just looked up its data sheet. What is the value of the current limit resistor you are using in your application? The 50Ω load suggests 200W of power at the 100v RMS you mention but the safe area of operation data for the MP 108 suggests this is not...
  14. globecollector

    Triac Problem

    If there is nothing between the TRIAC and motor, then there is no snubber. The snubber needs to be across MT1 and MT2 of the TRIAC. Use the values I or others have given you, but to be really safe, place a 275v MOV across MT1 and MT2 also. Some comments for "young players" too...if you...
  15. globecollector

    Triac Problem

    Can you determine if the TRIAC has failed due to over voltage (i.e, back E.M.F. or other inductive effects from the motor), over current or simply overheating. If the original was in a TO-92 package, it can't be much of a TRIAC, or a motor for that matter either. I once had to fix a fan speed...
  16. globecollector

    Project help wanted

    Seems like you are trying to solve a problem that does not yet exist...put the cart before the horse so to speak. I would certainly be checking to see if such a device has not already been invented, patented and marketed.
  17. globecollector

    12vdc low amp to 120vac high amp flash/blink lamp inverter circuit?

    Keep the lamp for posterity and use LED's. Garaunateed the lamp would be made somewhere like G.E., Bucyrus and the plant long closed....so never replacable.
  18. globecollector

    120VAC to 12VDC Power Quality Problem? HELP!

    It does help if you have an oscilloscope, because then you can see of the "power" is "dirty" or pure DC. Bob does have a point about the converter....it will be a constant current converter as LED's require a current (which is proportional to their brightness) and they develop a fixed voltage...
  19. globecollector

    Fast Switching Relay for High frequency Signals

    There is not really anything that will do the job you require at the OUTPUT of the amplifier....and another question, what is the POWER being fed to the transducer? At that frequency and power the most likely transducer is a Piezo type device which is capacitive, so there will be impedance...
  20. globecollector

    3W LED dimmer

    Oh, only ONE L.E.D. .... You can still use the same chip because it is a constant current source...it simply "punches" a current down through the stack of L.E.D.s which can be any number from one to about thirty...least I think that is what the data sheet says. It is important to read the...
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