Search results

  1. alfa88

    Antique Radio Repair

    I'm about to take on an antique radio repair and have been getting some tips. One of which is to gently encase twisted wires in silicon sealer. the theory being that there may be a reason they were twisted in the 1st place (induction). My question is what brand/type should I get and is it easy...
  2. alfa88

    Common Terms

    Terms Thanks. I can wrap my mind around these explanations although I think one would need a mighty big crowbar to trip a 3rd rail fuse. Having worked at said electrified rail system I can attest that there is a heck of alot of potential there. .A bit off topic is the term they use for a...
  3. alfa88

    Common Terms

    There are some terms that get used that just seem to bother me. I get the concept it's just the labels that stick in my craw. #1: Flyback transformer. What make it any different from any other transformer? #2 Crowbar. Okay, maybe I'm not so clear on that one. #3 Bootup/ Boot strap. Where did...
  4. alfa88

    weird question... i think

    Au Contraire Your inquiry stuck in my head and I just came across this: http://www.jameco.com/Jameco/workshop/diy/magnetic.html?sp_rid=MTgyNDYwMDI5MTkS1&sp_mid=3633998 Some train systems also use something similar to track/control trains. The audio wavelength being ideal due to the...
  5. alfa88

    LED Organ Help

    A Schematic I was thinking of slapping one together myself. There's a schematic here: http://blog.makezine.com/archive/2010/10/circuit-skills-led-color-organ-spon.html If I'm not mistaken the question of color organs has been asked before on this forum. You might want to do a search here...
  6. alfa88

    Ferric chloride

    What can I say, I guess I'm just a cowboy. Anyway I use the premix stuff 99% time. The 1st Google link I saw DID spell out distilled water. There is a non ferric chloride method using hydrochloric acid and hydrogen peroxide out there and it's touted as infinitely reusable but getting the acid...
  7. alfa88

    Ferric chloride

    Anhydrous Ferric Chloride Do a Google search on Anhydrous Ferric Chloride (Dry). You'll find more info than I can give. I've used regular tap water but I suppose you're supposed to use distilled water. Find a suitable container. label it and you can reuse it a couple more times. Dispose of...
  8. alfa88

    Motor not turning on but drawing excessive current.

    My 1st. Thought I'm wondering if there is a starter capacitor on that motor. It may have gone bad.
  9. alfa88

    square to triangle waveform

    I vote for integrator It doesn't get much simpler.
  10. alfa88

    12V adapter and 12V 7Ah smf battery setup

    Failsafe Power For a fuse I'd pick a 1.5 amp. The failsafe block diagram is what is used in a transit control system.
  11. alfa88

    How to use a zener in this situation?

    Zeners Regular diodes in the one direction block current flow making them Ideal for rectification. Zener diodes will conduct to a predetermined voltage. Care has to be taken to limit current so as not to burn out the zener, i.e., series resistor. If the load on the zener is constant you're fine...
  12. alfa88

    Power supply for a circuit

    A Suggetion If you want to play it safe you can't go wrong adding the 9 Volt regulator circuit . I would suggest a 100uF cap. near the V+ input of the 386 for additional noise suppression.
  13. alfa88

    Better Late than Never

    Hello all. I thought it about time that I introduce myself after being here a while. My name is Gary and 1st. off let me thank those that have answered my various questions. I would imagine that my interest in electronics began when I was 2 years old when I got a healthy respect for electricity...
  14. alfa88

    Power supply for a circuit

    Also I forgot to add. Lose the regulator. The audio chip will be perfectly fine with 12 volts.
  15. alfa88

    Power supply for a circuit

    No Worries If I'm getting this right you are asking if a big power supply is going to harm your amplifier circuit. No. The amplifier circuit will only use the power it needs. It's sort of like asking if a truck battery will cause harm to a Vespa. Same answer.:D
  16. alfa88

    Monster 5-16V 18A Regulated Power supply

    I Lttle Knowlege Can Be... I hear ya. I've seen some pretty basic questions here. I did manage to find some tips on what you did with some determined Googling so I'll do some experimentation. Your comments about heaters hit home. My little heater seems to warm up with the least little...
  17. alfa88

    Monster 5-16V 18A Regulated Power supply

    More Video Where did you connect the pot and resistors to? I'd like to re-purpose an old ATX supply myself. How about some exploding cap and frying resistor vids?:D
  18. alfa88

    What is AC and DC?

    What is AC/DC Here is my simplistic explanation: DC (Direct Current) is the type of voltage one would get from a battery, lightning, static. An everyday example is a car battery. You have a positive terminal and a negative. Of course one can derive voltage from a generator where a coil...
  19. alfa88

    Simple circuit repair?

    Questions Which transistor was backwards? What did you choose for C9's replacement? You do know that type of capacitor is polarity sensitive. I believe the transistors are Q1 - Q3 are 2SC732 (NPN) and Q4 is 2SK30a (Nch. FET). Did the board show any signs of rework before you started?
  20. alfa88

    Drilling PCBs

    Dremel I use a Dremel, Dremel drill press stand and an optional adjustable chuck. The Dremel is a variable speed. I got drill bits via EBay for cheap. Have a nice sharp Xacto knife handy should you need to 'center any' holes.
Top