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  1. Replies
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    this is a wonderfully clear and concise analogy...

    this is a wonderfully clear and concise analogy of nyquist sampling restrictions
  2. yes- if you could put the cpu and the regulator...

    yes- if you could put the cpu and the regulator on top (like the photo you have of the imaging chip
    on top) with its upper surface exposed that would help a lot. we did some thermal imaging of a...
  3. 2: How will power dissipation work? Running at...

    2: How will power dissipation work? Running at 600 MHz, a Teensy 4.0 typically uses about 100 mA. Can this 12x12 mm package with another layer of insulating material really dissipate 0.5 watts? ...
  4. is the nosecone at least 6 inches or 12 inches...

    is the nosecone at least 6 inches or 12 inches tall? is it balsa wood?

    with some 0.125 od mini 50 ohm coax maybe you could bury a
    monopole w short drooping radials or a dipole in the nosecone....
  5. if you go with lora you can get 0.1 and 1 watt...

    if you go with lora you can get 0.1 and 1 watt modules. your range may get better rather than suffer
    because at 300 baud receiver sensitivity is an astounding 0.01 uv which is 20-24 db better than...
  6. power monitor

    do you have any way of ac line power monitoring for dropouts and glitches?

    a) if you are having a line voltage drop out every 5-7 days and if your sig gen starts up with a nasty glitch
    when...
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    i have a drone w gps - very small antenna....

    i have a drone w gps - very small antenna. outdoors lock 3-4+ sat usually takes 1-2 minits.

    indoors (tile roof) often takes 5-6 minits

    and as jonr says, once it has aquired, i can carry it...
  8. a friend of mine used to produce and sell those...

    a friend of mine used to produce and sell those 30-40 years ago.

    as i remember he used a pin diode optical sensor to detect a fast rising or falling edge as the bullet went over the traps.
    rising...
  9. speaking of whisker growth - do your homework...

    speaking of whisker growth - do your homework before your last cleaning of the board,
    some components of some cleansers/solvents that get left behind will actually accelerate
    whisker formation and...
  10. that hib current for tlc is way too high - should...

    that hib current for tlc is way too high - should be a few ua

    there are several things that lower the hib current - most important is to set pin 17 or whichever is the
    "5v out" pin to be an...
  11. i agree that it would be hard for that to cause...

    i agree that it would be hard for that to cause 20ms. i also agree that 20ms is a long time - especially on T4
    you may have to break down and write a super simple code that does nothing other than...
  12. if (who== PIN_AX) { if (AuxHigh())...

    if (who== PIN_AX) {
    if (AuxHigh()) digitalWrite(13,HIGH);

    if you you change above to be digitalWrite(13,HIGH); leaving off the if auxhi does it help?
  13. the logic anal display does not show that clear...

    the logic anal display does not show that clear on my display. are you timing from when the aux pin goes
    on the rcvr or from when you begin or end the serial stream into the transmitter? which...
  14. Replies
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    i think i remember seeing a post by Paul S a year...

    i think i remember seeing a post by Paul S a year or so ago discussing how NXP had a small register to control to trise tfall
    time for i/o pins (they had EMI reduction in mind) so software timing...
  15. had overlooked on the schematic -non inverting...

    had overlooked on the schematic -non inverting input of lm324 at ground - will not work as desired that way.
    non inverting input would have to be at 1.65 or so volts for proper action.

    edit - is...
  16. the lm324 has restricted input voltage common...

    the lm324 has restricted input voltage common mode range - 1.7 v from +supply and
    0v from -supply so if it is powered from 5v the inputs can go as high as 3.3 with no
    tolerance and no margin. the...
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    luni's advice to stock so as to bridge the gap is...

    luni's advice to stock so as to bridge the gap is a good one, altho you have probably waited too long.
    i have been designing hardware since 1975 and in the old days you could actually avoid single...
  18. seems feasible to me - give it a go. i had...

    seems feasible to me - give it a go. i had similar doubts about using Teensy LC to produce nice pseudo sine
    waves at up to 2 khz for modulation of an RF carrier (rather than sq waves to reduce...
  19. sometimes - i just last week had to remove one...

    sometimes - i just last week had to remove one pole after an op amp and before adc input on t4 to get
    a 3-6 db improvement in signal to noise. the t4 seems to spit more charge out the adc input than...
  20. yes - i have aref tied to 3.3 and should have...

    yes - i have aref tied to 3.3 and should have mentioned it and yes - that must be the default for reference because
    i never have used the adc_reference........

    glad you are on the air - don't...
  21. jonr - thanks for the feedback i got in a t4...

    jonr - thanks for the feedback

    i got in a t4 code that is a spectrum analyzer, fed in a very clean 10 khz 3vp-p sinewave, and saw the same 2nd harmonic
    size with and without those lines - so in...
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    tested teensyduino with arduino 1.8.13 this am -...

    tested teensyduino with arduino 1.8.13 this am - all ok w compile/run/serial monitor using codes
    containing adc functions for tlc, t36, t4. install 153 on top of 153b3, win7pro64

    do not know...
  23. here are excerpts from that code - even tho i did...

    here are excerpts from that code - even tho i did not need bandwidth i left conversion, sampling, and averaging
    as they had been for fast operation in a previous code because i am lazy - you will...
  24. design the divider for low current draw on the...

    design the divider for low current draw on the battery - in an almost identical situation where i needed
    to read batt v up to at least 14v (there was an ulta low iq regulator between batt and tlc) i...
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    more on 1.8.13 maybe the guys at Arduino are ok...

    more on 1.8.13
    maybe the guys at Arduino are ok after all - if you go into preferences and turn off
    "check for updates on start", get out of Arduino, shut down windows, reboot
    windows then that...
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    maybe not a miracle - Murphy never sleeps

    maybe not a miracle - Murphy never sleeps
  27. Replies
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    thanks for the feedback that is right - arduino...

    thanks for the feedback
    that is right - arduino 1.8.13 - since there is only one adc library in the teensy stuff i wonder why it had to think so hard

    very annoying item 1.8.13 - the engineering...
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    did closer inspection of compile reports re ADC...

    did closer inspection of compile reports re ADC under 1.53 beta 3 and found something that is not an error,
    not a warning, but i don't remember it from past releases. as per previous post TLC T36 T4...
  29. Replies
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    compiles using ADC library worked ok TLC, T35,...

    compiles using ADC library worked ok TLC, T35, T4. (of course using the new settings syntax i had to do for 1.52)
    ala
    adc->adc0->setAveraging(1);
    etc
    have not timed any ADC yet
  30. Replies
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    under win7pro64: uninstall arduino 1.8.5 (and...

    under win7pro64: uninstall arduino 1.8.5 (and teensyduino 1.52), install arduino 1.8.13, install teensyduino 1.53 beta 3,
    compiled and ran just fine several programs each for TLC, T36, T4. some TLC...
  31. Replies
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    if your generator is 0 to 3.3 no load and 0 to...

    if your generator is 0 to 3.3 no load and 0 to 3.3 when hooked to teensy then current load is not a player.
    have you looked at the gen both before and after connection to teensy? also - just be be...
  32. Replies
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    i would not say easy - depends on what kind of...

    i would not say easy - depends on what kind of soldering/de-soldering tools you have. good news it only has six leads,
    bad news is it has a thermal pad center bottom that i bet is soldered down...
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    that is the 3.3 v regulator how very hot but no...

    that is the 3.3 v regulator
    how very hot but no current ? - it normally takes LOTS of current to get real hot

    i have a thermal image to send you - how did you attach that photo?
    never mind - i...
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    i saw some syntax changes between TD 1.48 and...

    i saw some syntax changes between TD 1.48 and 1.52 that may relate to 1.53 betas?

    needed in 1.48
    adc->setAveraging(1,ADC_0);

    needed in 1.52
    adc->adc0->setAveraging(1);

    also - total crash...
  35. Replies
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    oddson - i agree carlosemello - you used the...

    oddson - i agree

    carlosemello - you used the word "piezo" - at a glance it might seem that you can just hook the output of a piezo
    sensor (high C high Z) to a mux/atod but that is problematic for...
  36. Replies
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    is a8 a default analog in? i have only used...

    is a8 a default analog in?

    i have only used a10 and a11 TLC and have used this declaration:
    const int readPin = A10;
    const int readPin2 = A11;

    and then this setup:
    pinMode(A10,...
  37. jonr is right - but if you have a scope check for...

    jonr is right - but if you have a scope check for oscillation on the regulator output after you add the
    cap - many low drop out regulators are sensitive to Cl and the esr of Cl ala they become...
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    i have never used a 3.2, have never used the a/d...

    i have never used a 3.2, have never used the a/d in the LC in a situation where i really cared about usable resolution,
    but with the 3.6 i have gotten a dynamic range of 70db which is equiv to 11.6...
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    campbell - that is an interesting observation. in...

    campbell - that is an interesting observation. in 1977 Motorola had a trademark term for their newest family
    of processors - "systems on silicon" - wrong. but things like the ridiculously complex ...
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    it it is any help, when i was testing T4 snooze i...

    it it is any help, when i was testing T4 snooze i started with example code Duff had put in the Snooze library
    such as some thing like DeepSleep_all_wakeups - you might compare your code with that -...
  41. cleaned up redundant code, no longer needs code...

    cleaned up redundant code, no longer needs code changes in isr2 depending on slow/fast task time, and the
    comments include editing one of the teensy core files so that the abort/recover time goes...
  42. there is a 2.2 ufd on the T4 board on that pin -...

    there is a 2.2 ufd on the T4 board on that pin - that is probably enough - leave room in your artwork for
    and external 10-22 ufd but you probably won't need it.
  43. when i sped it up to us=6250 and lg=625 the line...

    when i sped it up to us=6250 and lg=625 the line in isr2() "++tc" had to be commented to prevent skipping
    one task on a restart - who knows, at even faster task intervals it might have to become...
  44. as a final summary point here is the code for 8...

    as a final summary point here is the code for 8 timeslices/4 tasks using noinit. i am sure that a real C programmer
    could tighten it up and shrink it even further.

    in task2 either comment or...
  45. to add to that summary - the 4 task 8 timeslice...

    to add to that summary - the 4 task 8 timeslice (01020103) version using the noinit attribute method uses these TLC resources:
    pgm space 12%, ram space 26%, both pit timers, and the abort-recover...
  46. KurtE - have you run out of time for this? here...

    KurtE - have you run out of time for this? here instead of a code snippet is an entire pgm that boils it all down
    comes up tries to recover from maybe_saved - prints result,waits 5 seconds, re...
  47. KurtE - here is the top section of my pgm so you...

    KurtE - here is the top section of my pgm so you can see where i put your statements
    and also the compiler error listing - earlier in this thread you can see an eeprom solution
    that is the complete...
  48. jonr - this version compiles no warnings and the...

    jonr - this version compiles no warnings and the contents of the variables it is used on do live thru the soft restart !!!
    - best solution so far - thank you

    KurtE - compiler not happy - after...
  49. no dice - compiler comes back w "warning 'noinit'...

    no dice - compiler comes back w "warning 'noinit' attribute directive ignored -
    it compiles and of course variables are all zero after restart - but thank you
  50. thanks - will try and let you know

    thanks - will try and let you know
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