Search results

Search Forums New Posts
  1. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    Have you noticed the bug with the camera? It fails to turn off the IR focus light when it makes an exposure. Silly camera!
  2. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    I think the board was being bent out of the factory. I couldn't push the connectors in any further, and the edge of the card touches the top of the case. Is this poor design? I guess a slightly bent board isn't a huge issue, but still, this wasn't a cheap instrument in its day! Two...
  3. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    Oh, look at that. Come on Stanford Research! No support at all!?! Why?
  4. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    I thought his timing was interesting. But this only goes to 100kHz, not his 100MHz :-/
  5. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    This little puppy cost me around $300, which is waaaaay cheap if it works. The seller has a second even cheaper unit that's on its way. If either one work is still a great price. If both work then I can probably sell one and cover the cost of both. If Jimi Hendrix is still playing, maybe I...
  6. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    A slightly better look at the front (which I've cleaned up a little) No sign of Jimi Hendrix yet.
  7. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    The back panel looks almost as complex as the front! I will investigate if I can get it to play Jimi Hendrix. I may have to get back to you...
  8. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    Pretty! Well, we all know what it is, and it doesn't look damaged in shipment (which I've experienced a few times too many). Time to set the line voltage then open it up and see what's inside.
  9. (*steve*)

    Successful Stanford Research SR530 lock-in amplifier repair

    Here is a new toy I received today... With a 3.5 inch hard drive, a small dog, and a large cat for scale. Doesn't look like the packaging is damaged. What is it? Will I need to repair it?
  10. (*steve*)

    How to measure diesel tank level by pressure sensor, tank area and diesel paramenters

    In comparison with refueling an aircraft it is. :-) I'm sure that truck drivers do fuel planning, and of course there are costs (other than the fuel) in stopping to refuel.
  11. (*steve*)

    How to measure diesel tank level by pressure sensor, tank area and diesel paramenters

    I think the issue here is that trucks don't carry a significant portion of their load as fuel and don't need to worry about balancing fuel load with payload. In addition, stopping for fuel mid-journey is cheap.
  12. (*steve*)

    Low-drain Long-life audio clicker

    I was almost expecting to see an LM3909!
  13. (*steve*)

    Design of a transistor curve tracer

    I don't know if any in the TO-3 package off the top of my head. What I would do is go to the digikey web site and just search for "mosfet". It should give you a list of options, one will be for "single mosfets" or something similar. Importantly, this option will have tends of thousands in...
  14. (*steve*)

    Pulse dropping circuit.

    But if there's 3V across the transistors, then the one with the forward biased BE has 2.3V across the reverse biased BC, and the other with the forward biased BC has 2.3V across the reverse biased BE.
  15. (*steve*)

    Dueling PWM speed controllers.

    Also allowing a window for acceptable positions so that you're not hunting for the exact position.
  16. (*steve*)

    Reducing music in videos

    If the soundtrack is stereo, you might find that dialog is less balanced between the channels than the background music. L-R might reduce the background.
  17. (*steve*)

    Pulse dropping circuit.

    What is the maximum reverse voltage seen across Q1 and Q2's BE junctions? Would the circuit's operation be badly disrupted if a diode (perhaps schottky) was placed in series with each emitter? Oh, I'm thinking about a 12V or higher supply. I think you have a 5V supply being used?
  18. (*steve*)

    PCB Laser Etching

    I've been using the laser ablation method of PCB manufacture for some time. edit: See here. Recently I've seen an approach where a blue laser is used to expose photosensitive PCB. The problem with all the laser ablation techniques is getting all the resist layer off without damaging...
  19. (*steve*)

    Got any ideas for using an old fridge?

    See how much you need to beware!
  20. (*steve*)

    Pulse dropping circuit.

    Here is my "2 of 3" circuit: The idea is that the 4017 counts up to 3, and passes the input to the output in 2 of these states. Note that the 4017 increments on the falling edge of the input pulse to prevent odd glitches. Schmitt trigger inputs are used to square up the inputs. Significant...
Top