Image Map Image Map

Search:

Type: Posts; User: Dwight Elvey

Page 1 of 20 1 2 3 4

Search: Search took 0.05 seconds.

  1. Replies
    11
    Views
    134

    If it is a good quality scan, Al Kossow at...

    If it is a good quality scan, Al Kossow at aek@bitsavers.org might want to put it on the bitsavers page. Do ask him first before sending a pdf.
    I thought I might add that you will probably need to...
  2. Replies
    11
    Views
    134

    Here is a picture of a SIM4-03:...

    Here is a picture of a SIM4-03:
    http://www.bitsavers.org/components/intel/MCS4/SIM4-03_Brochure_Apr73.pdf
    It is suppose to be pin compatible with a SIM4-02. It even has the same attachments....
  3. Replies
    11
    Views
    134

    Pictures, please. Dwight

    Pictures, please.
    Dwight
  4. That is 2 of the types I mentioned. The Thevenin...

    That is 2 of the types I mentioned. The Thevenin type are usually used as buss terminators. They typically have an impedance of around 120 ohms. That is the impedance of ribbon cable.
    Dwight
  5. Remove C13. I'm sure you'll see a small hole in...

    Remove C13. I'm sure you'll see a small hole in the case. I can almost assure you it is C13.
    The R-pack was broken mechanically. It is possible that it was always broken. 100K is a relatively large...
  6. I some how doubt the claim that it was 10 times...

    I some how doubt the claim that it was 10 times faster and used less power. 4 phase did allow designing with latch only design but often wasted cycles to match data with clocks. It typically used...
  7. Consuming an entire track worth of memory for a...

    Consuming an entire track worth of memory for a track buffer in a CP/M memory seems like a lot of work when simply interleaving the floppy disk would deal with the desired effect. No big software...
  8. While not modifying the disk format and instead...

    While not modifying the disk format and instead modifying the software might seem like a better solution, it is a hack. Also, as Chuck noted, most controllers can read sequential sectors, easily....
  9. There are a number of variables on interleaving....

    There are a number of variables on interleaving. In HDOS, it always skips the next sector so 1:1 was always slow. It could handle 2:1 on loading programs but for BASIC to read data inputs it needed...
  10. Replies
    5
    Views
    128

    I'd think CP/M source code would be the most...

    I'd think CP/M source code would be the most useful. It not only show best practices, it also shows how CP/M uses register.
    Dwight
  11. Replies
    16
    Views
    477

    Most floppies use DMA and not direct port access...

    Most floppies use DMA and not direct port access to transfer data.
    At least that is what I recall.
    Dwight
  12. Replies
    28
    Views
    622

    The problem is likely the frequency. Most ESR...

    The problem is likely the frequency. Most ESR meters use 1KHz while switching supplies are in the ten's of KHz. Most analog RLC bridges, even those with internal oscillators, have the ability to use...
  13. Replies
    28
    Views
    622

    I've been using an old analog RLC bridge to check...

    I've been using an old analog RLC bridge to check ESR. It can measure inductance and resistance as well.
    All this in one box.
    Dwight
  14. Replies
    19
    Views
    528

    I will re-note by Robbbert, The 222 is a 2200...

    I will re-note by Robbbert,
    The 222 is a 2200 pf.
    Three digits like that are a multiply for the last digit.
    I do not recommend replacing many of the smaller value capacitors. Also, not any marked...
  15. Replies
    19
    Views
    528

    There are reason to use or not use ceramic caps...

    There are reason to use or not use ceramic caps in particular applications. My point of the failure was in normal usage. 4Kv on a 50V cap is a little beyond that. I have seen those in HV applications...
  16. Replies
    19
    Views
    528

    Ceramic capacitors are not likely to have failed...

    Ceramic capacitors are not likely to have failed and rarely need to be replaced. In my 48 years of repairing electronic equipment I've only seen one ceramic capacitor that had failed. It was an...
  17. Replies
    33
    Views
    1,086

    I hate that when that happens. Still a little...

    I hate that when that happens.
    Still a little more hot glue, a white LED, a resistor and a switch connected to the cheap $10 meter's battery, solves that problem. I may even try it my self, as I...
  18. The doubling of lines of text is an addressing...

    The doubling of lines of text is an addressing problem. One of the addresses to the RAM is stuck. There also looks to be some character problems, RAM or character ROM.

    We in the USA have a bunch...
  19. Replies
    33
    Views
    1,086

    Chuck, you can always hot glue one of the probes...

    Chuck, you can always hot glue one of the probes to the side of your meter. :)
    Dwight
  20. Replies
    33
    Views
    1,086

    An analog meter works better for checking...

    An analog meter works better for checking continuity but usually doesn't have a beeper. For most of my digital meter work, I use a cheap $10 meter from Harbor Freight. For serious digital work I use...
  21. Replies
    45
    Views
    2,024

    As was mentioned, one can measure diodes by...

    As was mentioned, one can measure diodes by lifting one lead. The zener is likely a greater back voltage than the meter you are using. Things like the 1K or 10K scale usually show open if over 2...
  22. Replies
    45
    Views
    2,024

    I don't see a picture with the cable. One of your...

    I don't see a picture with the cable. One of your post has an invalid pointer to a picture attachments. The diodes on this line may be related to the phase compare but may also be limiters. You need...
  23. Replies
    54
    Views
    2,055

    Hold the board up to a strong light. You can...

    Hold the board up to a strong light. You can usually see the connections. The deeper connections will be fuzzier. The connections are usually with 2 or 4 thinner traces to keep the power plains from...
  24. Replies
    45
    Views
    2,024

    The TA7634 looks to be an IC that is the...

    The TA7634 looks to be an IC that is the horizontal and vertical oscillator chip.
    I see that ebay has one that you can buy but you still are not doing what is needed. You need to trace the circuit...
  25. Replies
    37
    Views
    5,741

    Oops, your right. These also came with different...

    Oops, your right. These also came with different part number by different manufactures.
    Dwight
Results 1 to 25 of 500
Page 1 of 20 1 2 3 4