Search results

Search Forums New Posts
  1. S

    Heat Sealing ESD Bags?

    No votes for using an 'impulse' sealer, so fold-over and tape, it is. I have received a few parts in these aluminum foil looking bags, and they were sealed (I'm sure for humidity issues). I was just wondering how they sealed the bags. Maybe that heat-wheel hand-held tool I've seen is how...
  2. S

    seeking wiring help

    My input is to see if you can get info from the manufacturer. If no one knows the color code, you can open the camera, trace the connections, and figure it out that way.
  3. S

    Complementary pair transistors

    Heck, we did that in school forty years ago. (But I obviously don't remember the circuit). Commercial parts suppliers don't bother selling selected pairs. It's something you usually have your techs do for you when you're producing products. Finding the Beta (gain) is pretty simple from what...
  4. S

    Complementary pair transistors

    Examples of complementary transistor pairs: 2N3055(NPN) 2N2955(PNP) 2N2222(NPN) 2N2907(PNP) 2N3904(NPN) 2N3906(PNP)
  5. S

    Complementary pair transistors

    You just need to check data sheets. Complementary pairs, just means one is a PNP and the complement is NPN. (With complementary specifications). There are a lot of those around. I'm wondering if you're thinking about 'selected' pairs, which are sold in sets of two or more, that just means...
  6. S

    Heat Sealing ESD Bags?

    Yeah, I usually just use the see-through silver ESD bags. A surplus place was selling these ESD/humidity bags at a super-cheap price, so I thought I'd get them and try them, THEN started wondering about HOW I should use them. Checking prices on-line, these ESD/humidity bags cost a lot more...
  7. S

    Heat Sealing ESD Bags?

    I got a bunch of the ESD bags that look like aluminum foil. Suppposed to be for ESD and humidity protection. I've also got a heat-sealer that is described in the catalog as an 'impulse' sealer. It appears to work by sending a high current to a heating element in the sealer, that melts...
  8. S

    RCA 61456 (In a TO-3 Package)

    At the bottom of the box is a bag of RCA 61456 in a TO-3 Package. They don't show-up on Google either. Anybody know if these parts are some kind of proprietary number? I've got a lot of RCA 4xxxx TO-3 Power Transistors, they show-up on Google, but this one doesn't. Wondering if anybody...
  9. S

    RCA 39628 (In a TO-3 Package)

    I just got a bag of RCA 39628. My earliest RCA Data Book is from 1981, and the power transitors start at 40250. Does anybody know if these are early power transistors, or maybe power diodes? The places I Googled don't find anything for this part number. Thanks
  10. S

    audio bleeding between channels in the power amp stage of a mixer amp

    Not familiar with your equipment or what you've done while working on it. First thing I'd check, is any 'grounding', or sharing of common grounds in your re-work. You may be bleeding from one circuit to another . I'd start with what ever work you just did. Then I'd look at the common between...
  11. S

    Homemade Shunt Resistor.

    Trivia, I've done what Y2KEDDIE is talking about many times also. Just remember. you can only do that with a full carbon composition resistor. (Not a carbon film, or wire-wound resistor). Just my 2-cents worth.
  12. S

    What does C rating mean for batteries? Speed of discharge?

    Where are you getting these numbers from? Is it 40 degrees C, which would be 104 degrees F? Is this is theory test, or a data sheet, or what? (Like, are we talking coulombs or some other unit of measure?)
  13. S

    A Special Place In Hell For Yahoo

    I continually couldn't 'sign-out' of my yahoo acct, they kept feeding me a screen saying they had to have a secondary account listed, in case I ever lost my password. I got fed-up and mistakenly gave them my daughter's yahoo address as the 'savior' acct. I immediately got duplicates of my...
  14. S

    42MF231D/17 Tv Repair

    Simply adjusting a trimmer is not going to solve your problem, no trimmer just goes out of alignment like that by itself. Anytime you've got no picture, you've got a serious problem. I don't have a schematic, but if you're serious about repairing this, you need one. Without a schematic, no...
  15. S

    42MF231D/17 Tv Repair

    Make sure you're reading the voltage from a correct ground for that circuit.
  16. S

    Swamp cooler switch

    Been out of town for the holiday long-weekend. You just need a 5vdc relay (maybe two if you want the pump and motor on separate control circuits). Ensure that the relay contacts will handle the amperage and are rated at the 120VAC for the evap. Send the signal through your controller to...
  17. S

    Connector type

    I Googled 'parts for singer futura ce200' One of the first offerings says [PDF] CE-100 CE-200 which sends you to www.parts.singerco.com/CPpartCharts/Quantum/Futura_CE200.pdf That's a complete exploded diagram of your machine, with the parts list. somewhere on the singerco website is says you...
  18. S

    Connector type

    It might help if we knew the manufacturer and model number of your machine.
  19. S

    A worthy venture?

    Let me modify that last comment: I spent most of my life as and I&C Tech (Instrumentation and Control), A couple places hired me as an E&I Tech (Electrical Instrumentation). Now that I think about it, the E&I Tech seemed to be expected to work more with the electricians in the motor control...
  20. S

    Swamp cooler switch

    The motors I've seen are capable of low and high speed. But a lot of the wiring I've seen in houses just bypasses the low speed, and use a single switch to run the motor on high only. The pump switch is separate so you can turn the pump on, and let the water saturate the cooling pads before...
View older results
Top