Re: [time-nuts] OT - DC-10 gyros
I neglected to mention that. The DC resistance of the motor windings is
roughly 200 ohms. I estimate the power draw is < 2 watts. Haven't
measured the inductance.
I probably could just use some FETs and build a simple class-B amp. The
sine wave doesn't have to be absolutely pure. Frequency stability (at
least, in a real application) is more important, since the gyro response
depends upon the rotational speed of the wheel. Not that I'm going to
actually use it for anything other than just getting it working. :)
On 03/27/2013 6:21 PM, time-nuts-request@febo.com wrote:
For "thumbsized" gyros, the power-drain is probably very slight.
--
Bill Ezell
They said 'Windows or better'
so I used Linux.
The circuit I built used a ULN3751Z (TO-220) amplifier chip and some capacitors
to create the phase shifts for making 3 phase. Very simple oscillator circuit.
Haven't found the docs yet but found the unit itself.
On 3/27/2013 6:59 PM, Bill Ezell wrote:
I neglected to mention that. The DC resistance of the motor windings is
roughly 200 ohms. I estimate the power draw is < 2 watts. Haven't measured the
inductance.
I probably could just use some FETs and build a simple class-B amp. The sine
wave doesn't have to be absolutely pure. Frequency stability (at least, in a
real application) is more important, since the gyro response depends upon the
rotational speed of the wheel. Not that I'm going to actually use it for
anything other than just getting it working. :)
On 03/27/2013 6:21 PM, time-nuts-request@febo.com wrote:
For "thumbsized" gyros, the power-drain is probably very slight.
Hi
For that kind of power, I'd dig out an audio transformer and drive it with something like an LM-380.
Bob
On Mar 27, 2013, at 6:59 PM, Bill Ezell wje@quackers.net wrote:
I neglected to mention that. The DC resistance of the motor windings is roughly 200 ohms. I estimate the power draw is < 2 watts. Haven't measured the inductance.
I probably could just use some FETs and build a simple class-B amp. The sine wave doesn't have to be absolutely pure. Frequency stability (at least, in a real application) is more important, since the gyro response depends upon the rotational speed of the wheel. Not that I'm going to actually use it for anything other than just getting it working. :)
On 03/27/2013 6:21 PM, time-nuts-request@febo.com wrote:
For "thumbsized" gyros, the power-drain is probably very slight.
--
Bill Ezell
They said 'Windows or better'
so I used Linux.
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Hi Bill,
The rated voltage is probably 26V AC rather than 28. I bulit a 3 phase inverter for a test rig last year and just used 3 cheap MOSFET power amplifier kits off ebay. Changed the feedback C's to limit high frequency response and it was nice and stable. When testing put a automotive stop lamp ~20W 12V in series with the output, it will protect the output devices and provide a warning if things go wrong.
Robert G8RPI (CEng MRAeS, still use synchro stuff for the day job!)
From: Bill Ezell wje@quackers.net
To: time-nuts@febo.com
Sent: Wednesday, 27 March 2013, 22:59
Subject: Re: [time-nuts] OT - DC-10 gyros
I neglected to mention that. The DC resistance of the motor windings is roughly 200 ohms. I estimate the power draw is < 2 watts. Haven't measured the inductance.
I probably could just use some FETs and build a simple class-B amp. The sine wave doesn't have to be absolutely pure. Frequency stability (at least, in a real application) is more important, since the gyro response depends upon the rotational speed of the wheel. Not that I'm going to actually use it for anything other than just getting it working. :)
On 03/27/2013 6:21 PM, time-nuts-request@febo.com wrote:
For "thumbsized" gyros, the power-drain is probably very slight.
-- Bill Ezell
They said 'Windows or better'
so I used Linux.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.