Stepper Motor

[Julius Fazekas n2wn]

Actually Vic, I think a few folks might be interested
in this topic on the reflector (for a while). I, too,
have a number of steppers and would like to use them
for remote tweaking of a phased array.

I do know there are several controller kits available
and easily found. The question seems to be, what kind
of stepper do you have and exactly how do you wish to
control it? The are two options that seem to be the
most flexible, using a "Basic Stamp" or a PIC.

If you have something like the PIC-EL kit from AmQRP
already, then the PIC option may be the easiest to
work with first. From what I've read a lot of the
robot folks seem to like the stamp approach.

Look forward to reading some other input, and maybe
some practical advice.
cheers,
Julius
n2wn


Message: 23
Date: Tue, 29 Mar 2005 10:31:12 -0800
From: Vic Rosenthal <[hidden email]>
Subject: [Elecraft] OT - stepper motor question
To: Elecraft Reflector <[hidden email]>
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=us-ascii;
format=flowed

I just know someone here can help me!  Please reply
off-reflector.

I recently had the opportunity to take apart a big old
Ricoh copy machine.  I recovered all kinds of neat
mechanical and electrical parts, inclucing
bunches of solenoids, motors, etc.

One of the coolest is a motor marked 55SPM-25D5A
AX050032 30V 6.5 [ohms symbol]. Google gets nothing on
either of these numbers.

It has 6 wires coming out of it.  On the basis of
this, and the 'coggy' feel when I turn the shaft, I
think that it is a permanent-magnet unipolar stepper
motor.

I want to build a remotely tuned very QRO L-network
antenna tuner (I already have a large rotary inductor
and capacitor).  What I want to do is use this stepper
to turn the capacitor to preset positions.  Once the
capacitor is set, I will be able to drive the inductor
with a simple geared motor and just tune for lowest
SWR.

Reading material on stepper motor control systems has
my head spinning! Is
there some kind of simple off-the-shelf controller
that I can get that will do most of the work?  What I
would REALLY like would be to just turn a local knob
to adjust the capacitor (sort of like the way a selsyn
acts), but there may be other approaches.

--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco

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[Vic K2VCO]

J F wrote:

> Actually Vic, I think a few folks might be interested
> in this topic on the reflector (for a while). I, too,
> have a number of steppers and would like to use them
> for remote tweaking of a phased array.
>
> I do know there are several controller kits available
> and easily found. The question seems to be, what kind
> of stepper do you have and exactly how do you wish to
> control it? The are two options that seem to be the
> most flexible, using a "Basic Stamp" or a PIC.

I've received a great deal of input from folks on the reflector.  What I have is
a unipolar motor, which turns out to have been manufactured by Panasonic.  I
also have since removed various other steppers from old disk drives.  I've
ordered a driver kit from <http://www.electronickits.com> for $23, and there is
one offered for $13 at <http://store.qkits.com/moreinfo.cfm/QK179>.

I think I am not going to try to control it with a microprocessor at first.  My
L-network tuner will have a rotary inductor and variable capacitor, and possibly
a relay to switch in a fixed capacitor.  I will first try to set it up so it can
be tuned remotely using switches, buttons, possibly an encoder, etc.  I will
also provide some kind of position feedback to help me find preset positions
quickly.  If I'm successful, then I will think about automatically finding
presets or even tuning to minimize SWR.

Controllers are available that interface directly to a PC.  One possible
application would be to completely control a remote K2 -- including the RF and
AF gain controls -- from a PC.

--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco

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[Julius Fazekas n2wn]

Vic,
there was an article in QST a few years back on an
automatic antenna tuner that used steppers. The
feedback control used a basic stamp as I recall. It
was adaptable, if you want to write/modify code.

You may want to think about the rotary inductor. A
school of thought has it that they are slow beasts to
turn. Switching inductance in and out seems to be
faster and easier to control. If you're primarily a CW
op, switching is probably the simplest route to go. On
the other hand, if you do say CW/SSB/MARS a rotary
inductor makes more sense.

Thanks for the update!
Julius
n2wn

--- Vic Rosenthal <[hidden email]> wrote:

> J F wrote:
>
> > Actually Vic, I think a few folks might be
> interested
> > in this topic on the reflector (for a while). I,
> too,
> > have a number of steppers and would like to use
> them
> > for remote tweaking of a phased array.
> >
> > I do know there are several controller kits
> available
> > and easily found. The question seems to be, what
> kind
> > of stepper do you have and exactly how do you wish
> to
> > control it? The are two options that seem to be
> the
> > most flexible, using a "Basic Stamp" or a PIC.
>
> I've received a great deal of input from folks on
> the reflector.  What I have is
> a unipolar motor, which turns out to have been
> manufactured by Panasonic.  I
> also have since removed various other steppers from
> old disk drives.  I've
> ordered a driver kit from
> <http://www.electronickits.com> for $23, and there
> is
> one offered for $13 at
> <http://store.qkits.com/moreinfo.cfm/QK179>.
>
> I think I am not going to try to control it with a
> microprocessor at first.  My
> L-network tuner will have a rotary inductor and
> variable capacitor, and possibly
> a relay to switch in a fixed capacitor.  I will
> first try to set it up so it can
> be tuned remotely using switches, buttons, possibly
> an encoder, etc.  I will
> also provide some kind of position feedback to help
> me find preset positions
> quickly.  If I'm successful, then I will think about
> automatically finding
> presets or even tuning to minimize SWR.
>
> Controllers are available that interface directly to
> a PC.  One possible
> application would be to completely control a remote
> K2 -- including the RF and
> AF gain controls -- from a PC.
>
> --
> 73,
> Vic, K2VCO
> Fresno CA
> http://www.qsl.net/k2vco
>
>

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[N2TK]

Would be nice to have some kind of control to vary my vacuum variable cap on
the shunt fed tower for 160M. A control like I have for my Vactrol's on the
pennant antennas would be nice. I have the pot marked for 160, 80 and 75M.
These settings correspond to the best F/B. Would like to use a similar type
setting system marked from 1.8-2.0MHZ. The settings would correspond to the
best swr for those frequencies. Use some kind of motor/selsyn drive on the
cap?
Would appreciate any feedback on ideas for this.
N2TK, Tony



-----Original Message-----
From: [hidden email]
[mailto:[hidden email]]On Behalf Of J F
Sent: Wednesday, March 30, 2005 8:08 AM
To: [hidden email]
Cc: Elecraft Discussion List
Subject: [Elecraft] Stepper Motor

Actually Vic, I think a few folks might be interested
in this topic on the reflector (for a while). I, too,
have a number of steppers and would like to use them
for remote tweaking of a phased array.

I do know there are several controller kits available
and easily found. The question seems to be, what kind
of stepper do you have and exactly how do you wish to
control it? The are two options that seem to be the
most flexible, using a "Basic Stamp" or a PIC.

If you have something like the PIC-EL kit from AmQRP
already, then the PIC option may be the easiest to
work with first. From what I've read a lot of the
robot folks seem to like the stamp approach.

Look forward to reading some other input, and maybe
some practical advice.
cheers,
Julius
n2wn


Message: 23
Date: Tue, 29 Mar 2005 10:31:12 -0800
From: Vic Rosenthal <[hidden email]>
Subject: [Elecraft] OT - stepper motor question
To: Elecraft Reflector <[hidden email]>
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=us-ascii;
format=flowed

I just know someone here can help me!  Please reply
off-reflector.

I recently had the opportunity to take apart a big old
Ricoh copy machine.  I recovered all kinds of neat
mechanical and electrical parts, inclucing
bunches of solenoids, motors, etc.

One of the coolest is a motor marked 55SPM-25D5A
AX050032 30V 6.5 [ohms symbol]. Google gets nothing on
either of these numbers.

It has 6 wires coming out of it.  On the basis of
this, and the 'coggy' feel when I turn the shaft, I
think that it is a permanent-magnet unipolar stepper
motor.

I want to build a remotely tuned very QRO L-network
antenna tuner (I already have a large rotary inductor
and capacitor).  What I want to do is use this stepper
to turn the capacitor to preset positions.  Once the
capacitor is set, I will be able to drive the inductor
with a simple geared motor and just tune for lowest
SWR.

Reading material on stepper motor control systems has
my head spinning! Is
there some kind of simple off-the-shelf controller
that I can get that will do most of the work?  What I
would REALLY like would be to just turn a local knob
to adjust the capacitor (sort of like the way a selsyn
acts), but there may be other approaches.

--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco

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Post to: [hidden email]
You must be a subscriber to post to the list.
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[n6wg]

Tony
Here is one idea.
I use a reversible geared down 12v dc motor to turn my tuning cap at the
base of my
vertical.  Typically I peak the vertical at either 1815 kHz or 1845 kHz.  I
have to tune
at low power and watch the swr meter for a minimum.

For the coming winter I'm going to build a noise bridge that can be put in
line
and switched in and out at the same time I'm doing tuning.  The receiver
will
be the null detector and I won't have to transmit any signal at all.

With this scheme I will be able to pick a frequency, peak the antenna, and
never put
out a signal ntil I'm ready.

Good luck and 73
Bob N6WG

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]]On Behalf Of N2TK, Tony
Sent: Thursday, March 31, 2005 4:29 AM
To: 'J F'; [hidden email]
Cc: 'Elecraft Discussion List'
Subject: RE: [Elecraft] Stepper Motor


Would be nice to have some kind of control to vary my vacuum variable cap on
the shunt fed tower for 160M. A control like I have for my Vactrol's on the
pennant antennas would be nice. I have the pot marked for 160, 80 and 75M.
These settings correspond to the best F/B. Would like to use a similar type
setting system marked from 1.8-2.0MHZ. The settings would correspond to the
best swr for those frequencies. Use some kind of motor/selsyn drive on the
cap?
Would appreciate any feedback on ideas for this.
N2TK, Tony



-----Original Message-----
From: [hidden email]
[mailto:[hidden email]]On Behalf Of J F
Sent: Wednesday, March 30, 2005 8:08 AM
To: [hidden email]
Cc: Elecraft Discussion List
Subject: [Elecraft] Stepper Motor

Actually Vic, I think a few folks might be interested
in this topic on the reflector (for a while). I, too,
have a number of steppers and would like to use them
for remote tweaking of a phased array.

I do know there are several controller kits available
and easily found. The question seems to be, what kind
of stepper do you have and exactly how do you wish to
control it? The are two options that seem to be the
most flexible, using a "Basic Stamp" or a PIC.

If you have something like the PIC-EL kit from AmQRP
already, then the PIC option may be the easiest to
work with first. From what I've read a lot of the
robot folks seem to like the stamp approach.

Look forward to reading some other input, and maybe
some practical advice.
cheers,
Julius
n2wn


Message: 23
Date: Tue, 29 Mar 2005 10:31:12 -0800
From: Vic Rosenthal <[hidden email]>
Subject: [Elecraft] OT - stepper motor question
To: Elecraft Reflector <[hidden email]>
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=us-ascii;
format=flowed

I just know someone here can help me!  Please reply
off-reflector.

I recently had the opportunity to take apart a big old
Ricoh copy machine.  I recovered all kinds of neat
mechanical and electrical parts, inclucing
bunches of solenoids, motors, etc.

One of the coolest is a motor marked 55SPM-25D5A
AX050032 30V 6.5 [ohms symbol]. Google gets nothing on
either of these numbers.

It has 6 wires coming out of it.  On the basis of
this, and the 'coggy' feel when I turn the shaft, I
think that it is a permanent-magnet unipolar stepper
motor.

I want to build a remotely tuned very QRO L-network
antenna tuner (I already have a large rotary inductor
and capacitor).  What I want to do is use this stepper
to turn the capacitor to preset positions.  Once the
capacitor is set, I will be able to drive the inductor
with a simple geared motor and just tune for lowest
SWR.

Reading material on stepper motor control systems has
my head spinning! Is
there some kind of simple off-the-shelf controller
that I can get that will do most of the work?  What I
would REALLY like would be to just turn a local knob
to adjust the capacitor (sort of like the way a selsyn
acts), but there may be other approaches.

--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
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[Julius Fazekas n2wn]

Bob,

You may be able to attach a pot to the capacitor shaft
somehow and pass a voltage to a meter. You already
have a voltage at the motor, the rest is probably in
your junk box already. Tune up and note the readings
at each frequency of interest, then just drive back to
the appropriate setting.
It's cheap and dirty, but easy.
73,
Julius
n2wn

--- Robert Tellefsen <[hidden email]> wrote:

> Tony
> Here is one idea.
> I use a reversible geared down 12v dc motor to turn
> my tuning cap at the
> base of my
> vertical.  Typically I peak the vertical at either
> 1815 kHz or 1845 kHz.  I
> have to tune
> at low power and watch the swr meter for a minimum.
>
> For the coming winter I'm going to build a noise
> bridge that can be put in
> line
> and switched in and out at the same time I'm doing
> tuning.  The receiver
> will
> be the null detector and I won't have to transmit
> any signal at all.
>
> With this scheme I will be able to pick a frequency,
> peak the antenna, and
> never put
> out a signal ntil I'm ready.
>
> Good luck and 73
> Bob N6WG
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf
> Of N2TK, Tony
> Sent: Thursday, March 31, 2005 4:29 AM
> To: 'J F'; [hidden email]
> Cc: 'Elecraft Discussion List'
> Subject: RE: [Elecraft] Stepper Motor
>
>
> Would be nice to have some kind of control to vary
> my vacuum variable cap on
> the shunt fed tower for 160M. A control like I have
> for my Vactrol's on the
> pennant antennas would be nice. I have the pot
> marked for 160, 80 and 75M.
> These settings correspond to the best F/B. Would
> like to use a similar type
> setting system marked from 1.8-2.0MHZ. The settings
> would correspond to the
> best swr for those frequencies. Use some kind of
> motor/selsyn drive on the
> cap?
> Would appreciate any feedback on ideas for this.
> N2TK, Tony
>
>
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf
> Of J F
> Sent: Wednesday, March 30, 2005 8:08 AM
> To: [hidden email]
> Cc: Elecraft Discussion List
> Subject: [Elecraft] Stepper Motor
>
> Actually Vic, I think a few folks might be
> interested
> in this topic on the reflector (for a while). I,
> too,
> have a number of steppers and would like to use them
> for remote tweaking of a phased array.
>
> I do know there are several controller kits
> available
> and easily found. The question seems to be, what
> kind
> of stepper do you have and exactly how do you wish
> to
> control it? The are two options that seem to be the
> most flexible, using a "Basic Stamp" or a PIC.
>
> If you have something like the PIC-EL kit from AmQRP
> already, then the PIC option may be the easiest to
> work with first. From what I've read a lot of the
> robot folks seem to like the stamp approach.
>
> Look forward to reading some other input, and maybe
> some practical advice.
> cheers,
> Julius
> n2wn
>
>
> Message: 23
> Date: Tue, 29 Mar 2005 10:31:12 -0800
> From: Vic Rosenthal <[hidden email]>
> Subject: [Elecraft] OT - stepper motor question
> To: Elecraft Reflector <[hidden email]>
> Message-ID: <[hidden email]>
> Content-Type: text/plain; charset=us-ascii;
> format=flowed
>
> I just know someone here can help me!  Please reply
> off-reflector.
>
> I recently had the opportunity to take apart a big
> old
> Ricoh copy machine.  I recovered all kinds of neat
> mechanical and electrical parts, inclucing
> bunches of solenoids, motors, etc.
>
> One of the coolest is a motor marked 55SPM-25D5A
> AX050032 30V 6.5 [ohms symbol]. Google gets nothing
> on
> either of these numbers.
>
> It has 6 wires coming out of it.  On the basis of
> this, and the 'coggy' feel when I turn the shaft, I
> think that it is a permanent-magnet unipolar stepper
> motor.
>
> I want to build a remotely tuned very QRO L-network
> antenna tuner (I already have a large rotary
> inductor
> and capacitor).  What I want to do is use this
> stepper
> to turn the capacitor to preset positions.  Once the
> capacitor is set, I will be able to drive the
> inductor
> with a simple geared motor and just tune for lowest
> SWR.
>
> Reading material on stepper motor control systems
> has
> my head spinning! Is
> there some kind of simple off-the-shelf controller
> that I can get that will do most of the work?  What
> I
> would REALLY like would be to just turn a local knob
> to adjust the capacitor (sort of like the way a
> selsyn
> acts), but there may be other approaches.
>
> --
> 73,
> Vic, K2VCO
> Fresno CA
> http://www.qsl.net/k2vco
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
>  http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
>  http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>
>

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[Dave Anderson, K4SV]

Hi All,

Yesterday I finished assembling my KX1 SN 1069 and
everything works or so it seemed.

In testing the receiver it heard a signal on 40 meters
at .1 uV well and on 20 meters it was a bit less
sensitive at .2 uV.  As receivers go, not bad.

In testing the transmitter it too worked but here is
my problem.  With a 12 volt external power supply I am
only able to get 2.5 watts out on 40 and almost 2 on
20 meters. No, the power does not sag.

I am a hardware engineer so I am not new to circuitry
and this kind of device.  I did the usual rechecking
of my work, verified parts values (visually), solder
connections, toroids ETC. I inspected the PCB under a
microscope for good connections.

Before I jump in and tear it apart I am hoping one of
you have had this problem and direct me to the source
of trouble.

Other than low power the rig works OK and I might say
very well.

All help appreciated.

K4SV
Dave...


               
__________________________________
Do you Yahoo!?
Yahoo! Personals - Better first dates. More second dates.
http://personals.yahoo.com

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[N2TK]

Tnx for the feedback. Want to make it as seamless as possible. Don't want to
have to tune anything. I still have the option of switching in fixed value
caps to change the band segment to have a decent swr. If possible without a
ton of work, would like the ides of varying a calibrated pot in the shack to
have minimum swr at the part of the  band of interest.
73,
N2TK, Tony



-----Original Message-----
From: J F [mailto:[hidden email]]
Sent: Thursday, March 31, 2005 1:48 PM
To: Robert Tellefsen; [hidden email]; [hidden email]
Cc: 'Elecraft Discussion List'
Subject: RE: [Elecraft] Stepper Motor

Bob,

You may be able to attach a pot to the capacitor shaft
somehow and pass a voltage to a meter. You already
have a voltage at the motor, the rest is probably in
your junk box already. Tune up and note the readings
at each frequency of interest, then just drive back to
the appropriate setting.
It's cheap and dirty, but easy.
73,
Julius
n2wn

--- Robert Tellefsen <[hidden email]> wrote:

> Tony
> Here is one idea.
> I use a reversible geared down 12v dc motor to turn
> my tuning cap at the
> base of my
> vertical.  Typically I peak the vertical at either
> 1815 kHz or 1845 kHz.  I
> have to tune
> at low power and watch the swr meter for a minimum.
>
> For the coming winter I'm going to build a noise
> bridge that can be put in
> line
> and switched in and out at the same time I'm doing
> tuning.  The receiver
> will
> be the null detector and I won't have to transmit
> any signal at all.
>
> With this scheme I will be able to pick a frequency,
> peak the antenna, and
> never put
> out a signal ntil I'm ready.
>
> Good luck and 73
> Bob N6WG
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf
> Of N2TK, Tony
> Sent: Thursday, March 31, 2005 4:29 AM
> To: 'J F'; [hidden email]
> Cc: 'Elecraft Discussion List'
> Subject: RE: [Elecraft] Stepper Motor
>
>
> Would be nice to have some kind of control to vary
> my vacuum variable cap on
> the shunt fed tower for 160M. A control like I have
> for my Vactrol's on the
> pennant antennas would be nice. I have the pot
> marked for 160, 80 and 75M.
> These settings correspond to the best F/B. Would
> like to use a similar type
> setting system marked from 1.8-2.0MHZ. The settings
> would correspond to the
> best swr for those frequencies. Use some kind of
> motor/selsyn drive on the
> cap?
> Would appreciate any feedback on ideas for this.
> N2TK, Tony
>
>
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf
> Of J F
> Sent: Wednesday, March 30, 2005 8:08 AM
> To: [hidden email]
> Cc: Elecraft Discussion List
> Subject: [Elecraft] Stepper Motor
>
> Actually Vic, I think a few folks might be
> interested
> in this topic on the reflector (for a while). I,
> too,
> have a number of steppers and would like to use them
> for remote tweaking of a phased array.
>
> I do know there are several controller kits
> available
> and easily found. The question seems to be, what
> kind
> of stepper do you have and exactly how do you wish
> to
> control it? The are two options that seem to be the
> most flexible, using a "Basic Stamp" or a PIC.
>
> If you have something like the PIC-EL kit from AmQRP
> already, then the PIC option may be the easiest to
> work with first. From what I've read a lot of the
> robot folks seem to like the stamp approach.
>
> Look forward to reading some other input, and maybe
> some practical advice.
> cheers,
> Julius
> n2wn
>
>
> Message: 23
> Date: Tue, 29 Mar 2005 10:31:12 -0800
> From: Vic Rosenthal <[hidden email]>
> Subject: [Elecraft] OT - stepper motor question
> To: Elecraft Reflector <[hidden email]>
> Message-ID: <[hidden email]>
> Content-Type: text/plain; charset=us-ascii;
> format=flowed
>
> I just know someone here can help me!  Please reply
> off-reflector.
>
> I recently had the opportunity to take apart a big
> old
> Ricoh copy machine.  I recovered all kinds of neat
> mechanical and electrical parts, inclucing
> bunches of solenoids, motors, etc.
>
> One of the coolest is a motor marked 55SPM-25D5A
> AX050032 30V 6.5 [ohms symbol]. Google gets nothing
> on
> either of these numbers.
>
> It has 6 wires coming out of it.  On the basis of
> this, and the 'coggy' feel when I turn the shaft, I
> think that it is a permanent-magnet unipolar stepper
> motor.
>
> I want to build a remotely tuned very QRO L-network
> antenna tuner (I already have a large rotary
> inductor
> and capacitor).  What I want to do is use this
> stepper
> to turn the capacitor to preset positions.  Once the
> capacitor is set, I will be able to drive the
> inductor
> with a simple geared motor and just tune for lowest
> SWR.
>
> Reading material on stepper motor control systems
> has
> my head spinning! Is
> there some kind of simple off-the-shelf controller
> that I can get that will do most of the work?  What
> I
> would REALLY like would be to just turn a local knob
> to adjust the capacitor (sort of like the way a
> selsyn
> acts), but there may be other approaches.
>
> --
> 73,
> Vic, K2VCO
> Fresno CA
> http://www.qsl.net/k2vco
>
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[Tony Wells]

> I still have the option of switching in fixed value
> caps to change the band segment to have a decent swr.

Tony, You may have already considered and rejected this, but have you
considered the old zener diode/relay stacking method to switch in
caps/inductances - you control the number of relays switched by the voltage
applied.

Regards

Tony
G7IGG

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