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Type: Posts; User: JST

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  1. Replies
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    The original plan, since the germans were not...

    The original plan, since the germans were not stupid, and understood the V1 was vulnerable, was to send them over in huge lots simultaneously. That way good numbers would get through. It basically...
  2. The thing about that summing circuit is that you...

    The thing about that summing circuit is that you can do all the summing from unbalanced inputs (one side grounded), because sum, difference, etc can be done in the circuit instead of via connections...
  3. That is quite a decent idea. And doing that...

    That is quite a decent idea. And doing that would potentially allow using buffers on the input if that is still needed.

    This assumes the input network is reasonably simple and can be changed in...
  4. It sounds as if the coil type sensors are...

    It sounds as if the coil type sensors are ungrounded because they are being connected in the "various ways" that would not work right as op-amp outputs.

    In that case, can you "break into" the...
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    There is the direct "too fast" where the "on"...

    There is the direct "too fast" where the "on" time is too short as you describe.

    The "speed" of switching can mean the actual speed of the switching event, or it can mean the number of times per...
  6. The simplest method would be to use an opamp on...

    The simplest method would be to use an opamp on each input, with the gain set at unity gain, and then use the outputs of those, which will be quite low impedance, as the input to your network.
    ...
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    And that is an example of the insulation...

    And that is an example of the insulation placement difference. High voltage spikes create corona voltages in susceptible spots, and that gradually breaks down insulation. Eventually something goes...
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    That's the full deal.... takes away all the...

    That's the full deal.... takes away all the noise, and lets through pretty nuch only the sine wave 60(50) Hz. Does not get any better than that

    Those can confuse anything past a regular V/hz...
  9. Engineering is generally closed just to keep new...

    Engineering is generally closed just to keep new items secret. Auto companies have a lot to keep secret from competitors. Iknow I could pick up a lot of data if I went on a tour that was supposed...
  10. Motor impedance, composed of inductance and...

    Motor impedance, composed of inductance and resistance, limits turn-on surge. A motor with a low impedance will have a hellacious turn-on surge,potentially damaging to the motor. But, a low...
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    Close... The inductor, assuming its value is...

    Close...

    The inductor, assuming its value is reasonable compared to the motor inductance, will simply "block" much of the high frequencies. That tends to reduce the peak voltage of the...
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    We should mention that longer parts may need a...

    We should mention that longer parts may need a "traveling steady" that holds the work and prevents it from pushing away from the tool as much. The work is part of the "structure" as much as the...
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    A couple added comments. The crosslide or...

    A couple added comments.

    The crosslide or compound indeed could be moving side to side, which is "usually" a gib (jib) adjustment. A row of screws along the side adjusts this.

    Problem is that...
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    The insulation placement on old motors is often...

    The insulation placement on old motors is often better than on newer ones. That usually offsets the margin provided by better insulation types on newer motors, vs the varnished paper or cloth in...
  15. Th point of secondary side grounding has almost...

    Th point of secondary side grounding has almost zero to do with fault currents from shorts to ground on the secondary.... An ungrounded secondary has NO fault current with a single point ground,...
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    A couple things. Bring the ground and not the...

    A couple things.

    Bring the ground and not the neutral. The ground is not supposed to have enything flowing in it other than fault currents. Neutral has other current in it.

    The neutral is...
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    The motor switch really needs to be rated for the...

    The motor switch really needs to be rated for the motor HP (for what it controls). That will take care of switching off with locked rotor current flowing, etc. Motor controls are generally HP...
  18. Concur that a repair is unlikely to work. That...

    Concur that a repair is unlikely to work.

    That part is really pretty heavily stressed. I have a Lambert, which originally had a square socket in the crank, fitting a square end on the bottom...
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    They would indeed likely be intended to better...

    They would indeed likely be intended to better hold up the generated leg. That's all that is really different about the generated leg vs the "pass-through". Might be a slightly different waveform...
  20. Thread: Hole punch angles

    by JST
    Replies
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    561

    I have a large set of arch punches to an inch or...

    I have a large set of arch punches to an inch or more diameter. Most seem to have soemthing between 30 and 45 degrees included angle per side. it can be hard to measure or estimate the angle on...
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    And you can basically consider oil tarps to be...

    And you can basically consider oil tarps to be plastic.... they have about the same effect, they do not "breathe"..
  22. The pulley is fairly easy. Just set up for...

    The pulley is fairly easy. Just set up for some known nameplate speed of the spindle, then turn the input pulley by hand and count turns per turn. Divide spindle speed by that ratio. Now, you...
  23. INSIDE a machine, all bets are off.... there is...

    INSIDE a machine, all bets are off.... there is no absolute functional need to ground anything, although it is still a good idea, and an ungrounded winding SHOULD be only with a double-insulated...
  24. Motors are motors. If it works as a motor it...

    Motors are motors. If it works as a motor it works as an idler.

    I tend to prefer an older motor with more iron, but a newer "efficient" motor can have some advantages. But no need to pay more...
  25. You are using this to make 480 single phase,...

    You are using this to make 480 single phase, created from 240V source, correct?

    There is no single phase 480V service with a grounded center tap, that only occurs for 240V, because that is...
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