Greetings:



I have a Piper Altimatic II autopilot in my '64 C model Aztec which has been
in-op since I bought the airplane. I bought a service manual for this
autopilot with the idea of learning how it was supposed to work, and with
the hope of , maybe, just maybe, getting it to work and having it returned
to service. Yes, I know the unit is obsolete. Yes, I know the unit is
worthless. Yes, I know that most autopilot shops say the units are not
worth messing with. And yes,

I'm not inclined to spend / waste much money on it.



But, as an engineer and tinker, I am inclined to spend a little time
investigating. If it was good enough to be certified in the airplane, the
design once worked and it should still be able to do the job it was designed
for. I'm also inspired by a friend of mine who inherited his grandfather's
1947 Bonanza. He has been able to get the pneumatic based autopilot (yes, I
do mean air controls) in that airplane working and it works quite well. If
his pneumatic analog computer can be made to work, surely my germanium
transistor analog computer can also be made to work.



Therefore, I'd be very interesting in getting any information such as:



- A schematic of the console amplifier. The service manual does not include
one.



- Any theory of operation document for the console amplifier and/or the
radio coupler. The service manual has a good overall theory of operation
for the autopilot system, but does not go into the details for any of the
electronic components.



- Any old test equipment / test boxes that were designed to service and
adjust this AP.

The service manual lists some test boxes made by Mitchell.



- Any pieces and parts of any Altimatic II, (or Autocontrol II) such as the
RF gyros, console amplifier, control head, radio coupler, altitude bellows,
and servos (roll, pitch, trim) that you'd like to part with. If you have
any pieces and parts that might be useful for spare parts, I'd like to talk
to you.



- Leads to anyone who has experience working on these units, including
component level repair of the electronics. I'd love to find an experienced
technician / engineer that knows these units inside and out and who would
love to see one brought back to life.



- Any "been there, done that", "been there, tried that", type of stories,
positive or negative, from the group.



Again, I know this is a long shot, but I'm willing to invest some time and
energy to see what can be done. As a bare minimum, I'll learn a bunch.



Thanks,



Ronnie

> - Leads to anyone who has experience working on these units, including
> component level repair of the electronics. I'd love to find an
experienced
> technician / engineer that knows these units inside and out and who would
> love to see one brought back to life.
>

Hey Ronnie
Try:
Autopilots Central http://www.sparksaviationcenter.com/

Probably repeating something that you've already heard.

When we were Aztec shopping, we seriously considered a 65 C that had an
Altimatic II (inop) I called Autopilots Central and talked with them in
length about it's value and it's potential problems. They were very
patient, knowledgeable, and although they no longer work on them, answered
all my questions. I would definately give them a call.

Good luck.

Jim

Thanks Jim.

On a trip back from OSH 3 years ago, I had left engine trouble and
ended up making a stop in Tulsa, and the only FBO with maintenance
open on Saturday afternoon was Autopilots Central. I was impressed
with the place, and discussed the Altimatic II with the mechanic briefly.
But he said I needed to talk with the autopilot techs, which I've never
done. But I did learn that they didn't work on them any longer. I can
understand why. It is not exactly easy to find germanium transistors
these days. I work for a semiconductor company that is head quartered
in Silicon Valley, not Germanium Valley :-)

Anyway, thanks for the info. I think that is good advice.

Oh, BTW, what did you go with your old autopilot? Is it still in the
airplane, or did you throw it away? I'm hoping to find enough discarded
pieces and parts to be of some use.

Ronnie


"Jim Burns" > wrote in message
...
>
>> - Leads to anyone who has experience working on these units, including
>> component level repair of the electronics. I'd love to find an
> experienced
>> technician / engineer that knows these units inside and out and who would
>> love to see one brought back to life.
>>
>
> Hey Ronnie
> Try:
> Autopilots Central http://www.sparksaviationcenter.com/
>
> Probably repeating something that you've already heard.
>
> When we were Aztec shopping, we seriously considered a 65 C that had an
> Altimatic II (inop) I called Autopilots Central and talked with them in
> length about it's value and it's potential problems. They were very
> patient, knowledgeable, and although they no longer work on them, answered
> all my questions. I would definately give them a call.
>
> Good luck.
>
> Jim
>
>
>

Ignore my question about what you did with yours. I re-read your
post and see that was in an airplane you were considering, but did
not buy.

Ronnie

"Jim Burns" > wrote in message
...
>
>> - Leads to anyone who has experience working on these units, including
>> component level repair of the electronics. I'd love to find an
> experienced
>> technician / engineer that knows these units inside and out and who would
>> love to see one brought back to life.
>>
>
> Hey Ronnie
> Try:
> Autopilots Central http://www.sparksaviationcenter.com/
>
> Probably repeating something that you've already heard.
>
> When we were Aztec shopping, we seriously considered a 65 C that had an
> Altimatic II (inop) I called Autopilots Central and talked with them in
> length about it's value and it's potential problems. They were very
> patient, knowledgeable, and although they no longer work on them, answered
> all my questions. I would definately give them a call.
>
> Good luck.
>
> Jim
>
>
>

> Oh, BTW, what did you go with your old autopilot? Is it still in the
> airplane, or did you throw it away? I'm hoping to find enough discarded
> pieces and parts to be of some use.
>
> Ronnie

Bob Ferguson was the man that I talked to about the Altimatic II and I also
talked to him another time re our current S-Tec 60-2 and KLN94 regarding
GPSS roll steering (can't do it, the two are not compatible). Anyway, Bob
told me that unless the seller of the 65 C would take about $15 AMU's off
the price, forget about the airplane because that would be what it would
cost to rip out the old and install a new 2 axis, altitude hold, coupled AP.
Needless to say, we walked, and that was one of the main reasons.

Jim

nobody wrote:
> Greetings:
>
>
>
> I have a Piper Altimatic II autopilot in my '64 C model Aztec which has been
> in-op since I bought the airplane. I bought a service manual for this
> autopilot with the idea of learning how it was supposed to work, and with
> the hope of , maybe, just maybe, getting it to work and having it returned
> to service. Yes, I know the unit is obsolete. Yes, I know the unit is
> worthless. Yes, I know that most autopilot shops say the units are not
> worth messing with. And yes,
>
> I'm not inclined to spend / waste much money on it.
/snip/

Contact the folks at http://www.bevanrabell.com

Not sure about now, but they used to work on ALL the old stuff...

Happy Flying!
Scott Skylane
N92054

I'll check them out.
Thanks,
Ronnie

"Scott Skylane" > wrote in message
...
> nobody wrote:
>> Greetings:
>>
>>
>>
>> I have a Piper Altimatic II autopilot in my '64 C model Aztec which has
>> been in-op since I bought the airplane. I bought a service manual for
>> this autopilot with the idea of learning how it was supposed to work, and
>> with the hope of , maybe, just maybe, getting it to work and having it
>> returned to service. Yes, I know the unit is obsolete. Yes, I know the
>> unit is worthless. Yes, I know that most autopilot shops say the units
>> are not worth messing with. And yes,
>>
>> I'm not inclined to spend / waste much money on it.
> /snip/
>
> Contact the folks at http://www.bevanrabell.com
>
> Not sure about now, but they used to work on ALL the old stuff...
>
> Happy Flying!
> Scott Skylane
> N92054

Bevan Rabell is located in Wichita, Kansas at ICT.
In Novermber 2005 Bevan worked over the autopilot in a C-210M which I
sometimes fly.

Jim Burns wrote:
> > - Leads to anyone who has experience working on these units, including
> > component level repair of the electronics. I'd love to find an
> experienced
> > technician / engineer that knows these units inside and out and who would
> > love to see one brought back to life.
> >
>
> Hey Ronnie
> Try:
> Autopilots Central http://www.sparksaviationcenter.com/
>
> Probably repeating something that you've already heard.
>
> When we were Aztec shopping, we seriously considered a 65 C that had an
> Altimatic II (inop) I called Autopilots Central and talked with them in
> length about it's value and it's potential problems. They were very
> patient, knowledgeable, and although they no longer work on them, answered
> all my questions. I would definately give them a call.
>
> Good luck.
>
> Jim

I've had good luck with AutoPilot Central in Tulsa OK. Talked to Randy
Herren a couple of years ago and they work on and know Piper
Autopilots.

Chuck
Archer 2185B

I'll write more later, but I just had to report some sucess.

Long story short, the old Altimatic II is now working and it
works quite well. The wing lever / heading control / NAV &
LOC intercept and tracking all are working great. The pitch
control is working as is the altitude hold, but the altitude pre-select
calibration and its ability to command the airplane to climb or descent
at the correct airspeed to capture the selected altitude still needs some
adjustment. However, based on what I see so far, this should be a simple
matter of following the setup proceedure in the service manual
to make the necessary adjustments.

As it stands, I flew an ILS using only the autopilot controls for
intercepting and tracking the localizer and for controlling pitch
to stay on the glide slope. After living without an autopilot for
almost 6 years, it was a great feeling to see it work. The only real
issues were that the roll servo was loose in its mount allowing the drive
gears to slip and that the mechanical linkage between the pitch servo
the flight controls was loose. With those items tightened up, it came
to life.

Fooey on me for believing the previous owner when he told me
it was INOP and for not investigating it sooner.

Don't disount an old autopilot as being useless just because it is old and
someone elese tells you it is not worth messing with as I did for 6 years.
With just a little bit of effort, this one came back to life. Time will
tell how
it holds up, but since it was built in 1964 and is still working, I'm
hopeful
it will work for a few more years.

Ronnie

"nobody" > wrote in message
et...
> Greetings:
>
>
>
> I have a Piper Altimatic II autopilot in my '64 C model Aztec which has
> been in-op since I bought the airplane. I bought a service manual for
> this autopilot with the idea of learning how it was supposed to work, and
> with the hope of , maybe, just maybe, getting it to work and having it
> returned to service. Yes, I know the unit is obsolete. Yes, I know the
> unit is worthless. Yes, I know that most autopilot shops say the units
> are not worth messing with. And yes,
>
> I'm not inclined to spend / waste much money on it.
>
>
>
> But, as an engineer and tinker, I am inclined to spend a little time
> investigating. If it was good enough to be certified in the airplane, the
> design once worked and it should still be able to do the job it was
> designed for. I'm also inspired by a friend of mine who inherited his
> grandfather's 1947 Bonanza. He has been able to get the pneumatic based
> autopilot (yes, I do mean air controls) in that airplane working and it
> works quite well. If his pneumatic analog computer can be made to work,
> surely my germanium transistor analog computer can also be made to work.
>
>
>
> Therefore, I'd be very interesting in getting any information such as:
>
>
>
> - A schematic of the console amplifier. The service manual does not
> include one.
>
>
>
> - Any theory of operation document for the console amplifier and/or the
> radio coupler. The service manual has a good overall theory of operation
> for the autopilot system, but does not go into the details for any of the
> electronic components.
>
>
>
> - Any old test equipment / test boxes that were designed to service and
> adjust this AP.
>
> The service manual lists some test boxes made by Mitchell.
>
>
>
> - Any pieces and parts of any Altimatic II, (or Autocontrol II) such as
> the RF gyros, console amplifier, control head, radio coupler, altitude
> bellows, and servos (roll, pitch, trim) that you'd like to part with. If
> you have any pieces and parts that might be useful for spare parts, I'd
> like to talk to you.
>
>
>
> - Leads to anyone who has experience working on these units, including
> component level repair of the electronics. I'd love to find an
> experienced technician / engineer that knows these units inside and out
> and who would love to see one brought back to life.
>
>
>
> - Any "been there, done that", "been there, tried that", type of stories,
> positive or negative, from the group.
>
>
>
> Again, I know this is a long shot, but I'm willing to invest some time and
> energy to see what can be done. As a bare minimum, I'll learn a bunch.
>
>
>
> Thanks,
>
>
>
> Ronnie
>
>

Congrats!!! Good for you Ronnie! It's nice to see some news about something
actually working rather than another "my xxx is broken" :) If you've got
the service manual, you may want to check the cable tensions also, from what
I've heard, if the tension is off just a little it can cause an INOP
condition that is also easily solved.

Jim

"Ronnie" > wrote in message
et...
> I'll write more later, but I just had to report some sucess.
>
> Long story short, the old Altimatic II is now working and it
> works quite well. The wing lever / heading control / NAV &
> LOC intercept and tracking all are working great. The pitch
> control is working as is the altitude hold, but the altitude pre-select
> calibration and its ability to command the airplane to climb or descent
> at the correct airspeed to capture the selected altitude still needs some
> adjustment. However, based on what I see so far, this should be a simple
> matter of following the setup proceedure in the service manual
> to make the necessary adjustments.
>
> As it stands, I flew an ILS using only the autopilot controls for
> intercepting and tracking the localizer and for controlling pitch
> to stay on the glide slope. After living without an autopilot for
> almost 6 years, it was a great feeling to see it work. The only real
> issues were that the roll servo was loose in its mount allowing the drive
> gears to slip and that the mechanical linkage between the pitch servo
> the flight controls was loose. With those items tightened up, it came
> to life.
>
> Fooey on me for believing the previous owner when he told me
> it was INOP and for not investigating it sooner.
>
> Don't disount an old autopilot as being useless just because it is old and
> someone elese tells you it is not worth messing with as I did for 6 years.
> With just a little bit of effort, this one came back to life. Time will
> tell how
> it holds up, but since it was built in 1964 and is still working, I'm
> hopeful
> it will work for a few more years.
>
> Ronnie
>
> "nobody" > wrote in message
> et...
> > Greetings:
> >
> >
> >
> > I have a Piper Altimatic II autopilot in my '64 C model Aztec which has
> > been in-op since I bought the airplane. I bought a service manual for
> > this autopilot with the idea of learning how it was supposed to work,
and
> > with the hope of , maybe, just maybe, getting it to work and having it
> > returned to service. Yes, I know the unit is obsolete. Yes, I know the
> > unit is worthless. Yes, I know that most autopilot shops say the units
> > are not worth messing with. And yes,
> >
> > I'm not inclined to spend / waste much money on it.
> >
> >
> >
> > But, as an engineer and tinker, I am inclined to spend a little time
> > investigating. If it was good enough to be certified in the airplane,
the
> > design once worked and it should still be able to do the job it was
> > designed for. I'm also inspired by a friend of mine who inherited his
> > grandfather's 1947 Bonanza. He has been able to get the pneumatic based
> > autopilot (yes, I do mean air controls) in that airplane working and it
> > works quite well. If his pneumatic analog computer can be made to work,
> > surely my germanium transistor analog computer can also be made to work.
> >
> >
> >
> > Therefore, I'd be very interesting in getting any information such as:
> >
> >
> >
> > - A schematic of the console amplifier. The service manual does not
> > include one.
> >
> >
> >
> > - Any theory of operation document for the console amplifier and/or the
> > radio coupler. The service manual has a good overall theory of
operation
> > for the autopilot system, but does not go into the details for any of
the
> > electronic components.
> >
> >
> >
> > - Any old test equipment / test boxes that were designed to service and
> > adjust this AP.
> >
> > The service manual lists some test boxes made by Mitchell.
> >
> >
> >
> > - Any pieces and parts of any Altimatic II, (or Autocontrol II) such as
> > the RF gyros, console amplifier, control head, radio coupler, altitude
> > bellows, and servos (roll, pitch, trim) that you'd like to part with.
If
> > you have any pieces and parts that might be useful for spare parts, I'd
> > like to talk to you.
> >
> >
> >
> > - Leads to anyone who has experience working on these units, including
> > component level repair of the electronics. I'd love to find an
> > experienced technician / engineer that knows these units inside and out
> > and who would love to see one brought back to life.
> >
> >
> >
> > - Any "been there, done that", "been there, tried that", type of
stories,
> > positive or negative, from the group.
> >
> >
> >
> > Again, I know this is a long shot, but I'm willing to invest some time
and
> > energy to see what can be done. As a bare minimum, I'll learn a bunch.
> >
> >
> >
> > Thanks,
> >
> >
> >
> > Ronnie
> >
> >
>
>
>

Hi Jim,

I do have the service manual. It does not have any setup
information on cable tensions that I'm aware of.

Both the pitch and roll servo motors have a bevel gear which
engages with a bevel gear that is attached to its corresponding axis
of flight control. There are no cable attachment points in this autopilot.
It is hard coupled via gears into the flight controls. The manual override
of the autopilot is provided by a friction clucth mechanism within each
servo. There is a setup procedure for those. At a given amount of
force applied to the yoke in either pitch or roll, the corresponding clucth
must slip which allows the pilot to manually over-power the autopilot.

The pitch servo motor is slid back and forth to engage / dis-engage its
gears
while the roll servo motor is pivoted in its mount to accomplish engagement.
The pitch servo has an over-center latch to hold it in position while the
roll
servo depends only on the push of the cable to hold it engaged.

The control cables push / pull the servo motors much like a throttle
cable on a lawn mower. The cables are moved back and forth by a worm
gear mechanism in the control console when the pilot rotates the roll or
pitch
engagement controls. Within the first few degrees of rotation, micro
swicthes
in the servos activate to control power to the amp (and to disengage manual
electric
trim control) while the gears mesh during the last 10 to 20 degrees of
rotation.

I can see the potential problem if the engagement cables were not positioned
correctly and/or the cable housings were not securely clampled to the
servos.
In that case, the gears would not mesh properly. In fact, that was the
major
issue with my roll servo. The mounting screws were loose which allowed the
gears to slip rather that stay engaged. The service manual simply
states to set the cables such that the gears fully mesh.

There is a set-up procedure for the trim sensor which consists of
propely centering the trim sensor on the elevator cables, but I don't
recall any cable tension adjustments. I'll have to look at that closer.

Ronnie

"Jim Burns" > wrote in message
...
> Congrats!!! Good for you Ronnie! It's nice to see some news about
> something
> actually working rather than another "my xxx is broken" :) If you've got
> the service manual, you may want to check the cable tensions also, from
> what
> I've heard, if the tension is off just a little it can cause an INOP
> condition that is also easily solved.
>
> Jim
>
> "Ronnie" > wrote in message
> et...
>> I'll write more later, but I just had to report some sucess.
>>
>> Long story short, the old Altimatic II is now working and it
>> works quite well. The wing lever / heading control / NAV &
>> LOC intercept and tracking all are working great. The pitch
>> control is working as is the altitude hold, but the altitude pre-select
>> calibration and its ability to command the airplane to climb or descent
>> at the correct airspeed to capture the selected altitude still needs some
>> adjustment. However, based on what I see so far, this should be a simple
>> matter of following the setup proceedure in the service manual
>> to make the necessary adjustments.
>>
>> As it stands, I flew an ILS using only the autopilot controls for
>> intercepting and tracking the localizer and for controlling pitch
>> to stay on the glide slope. After living without an autopilot for
>> almost 6 years, it was a great feeling to see it work. The only real
>> issues were that the roll servo was loose in its mount allowing the drive
>> gears to slip and that the mechanical linkage between the pitch servo
>> the flight controls was loose. With those items tightened up, it came
>> to life.
>>
>> Fooey on me for believing the previous owner when he told me
>> it was INOP and for not investigating it sooner.
>>
>> Don't disount an old autopilot as being useless just because it is old
>> and
>> someone elese tells you it is not worth messing with as I did for 6
>> years.
>> With just a little bit of effort, this one came back to life. Time will
>> tell how
>> it holds up, but since it was built in 1964 and is still working, I'm
>> hopeful
>> it will work for a few more years.
>>
>> Ronnie
>>
>> "nobody" > wrote in message
>> et...
>> > Greetings:
>> >
>> >
>> >
>> > I have a Piper Altimatic II autopilot in my '64 C model Aztec which has
>> > been in-op since I bought the airplane. I bought a service manual for
>> > this autopilot with the idea of learning how it was supposed to work,
> and
>> > with the hope of , maybe, just maybe, getting it to work and having it
>> > returned to service. Yes, I know the unit is obsolete. Yes, I know
>> > the
>> > unit is worthless. Yes, I know that most autopilot shops say the units
>> > are not worth messing with. And yes,
>> >
>> > I'm not inclined to spend / waste much money on it.
>> >
>> >
>> >
>> > But, as an engineer and tinker, I am inclined to spend a little time
>> > investigating. If it was good enough to be certified in the airplane,
> the
>> > design once worked and it should still be able to do the job it was
>> > designed for. I'm also inspired by a friend of mine who inherited his
>> > grandfather's 1947 Bonanza. He has been able to get the pneumatic
>> > based
>> > autopilot (yes, I do mean air controls) in that airplane working and it
>> > works quite well. If his pneumatic analog computer can be made to
>> > work,
>> > surely my germanium transistor analog computer can also be made to
>> > work.
>> >
>> >
>> >
>> > Therefore, I'd be very interesting in getting any information such as:
>> >
>> >
>> >
>> > - A schematic of the console amplifier. The service manual does not
>> > include one.
>> >
>> >
>> >
>> > - Any theory of operation document for the console amplifier and/or the
>> > radio coupler. The service manual has a good overall theory of
> operation
>> > for the autopilot system, but does not go into the details for any of
> the
>> > electronic components.
>> >
>> >
>> >
>> > - Any old test equipment / test boxes that were designed to service and
>> > adjust this AP.
>> >
>> > The service manual lists some test boxes made by Mitchell.
>> >
>> >
>> >
>> > - Any pieces and parts of any Altimatic II, (or Autocontrol II) such as
>> > the RF gyros, console amplifier, control head, radio coupler, altitude
>> > bellows, and servos (roll, pitch, trim) that you'd like to part with.
> If
>> > you have any pieces and parts that might be useful for spare parts, I'd
>> > like to talk to you.
>> >
>> >
>> >
>> > - Leads to anyone who has experience working on these units, including
>> > component level repair of the electronics. I'd love to find an
>> > experienced technician / engineer that knows these units inside and out
>> > and who would love to see one brought back to life.
>> >
>> >
>> >
>> > - Any "been there, done that", "been there, tried that", type of
> stories,
>> > positive or negative, from the group.
>> >
>> >
>> >
>> > Again, I know this is a long shot, but I'm willing to invest some time
> and
>> > energy to see what can be done. As a bare minimum, I'll learn a
>> > bunch.
>> >
>> >
>> >
>> > Thanks,
>> >
>> >
>> >
>> > Ronnie
>> >
>> >
>>
>>
>>
>
>

Awesome explanation!! Hopefully the archive services will keep it handy for
future Altimatic II owners!!
Jim

"Ronnie" > wrote in message
t...
> Hi Jim,
>
> I do have the service manual. It does not have any setup
> information on cable tensions that I'm aware of.
>
> Both the pitch and roll servo motors have a bevel gear which
> engages with a bevel gear that is attached to its corresponding axis
> of flight control. There are no cable attachment points in this
autopilot.
> It is hard coupled via gears into the flight controls. The manual
override
> of the autopilot is provided by a friction clucth mechanism within each
> servo. There is a setup procedure for those. At a given amount of
> force applied to the yoke in either pitch or roll, the corresponding
clucth
> must slip which allows the pilot to manually over-power the autopilot.
>
> The pitch servo motor is slid back and forth to engage / dis-engage its
> gears
> while the roll servo motor is pivoted in its mount to accomplish
engagement.
> The pitch servo has an over-center latch to hold it in position while the
> roll
> servo depends only on the push of the cable to hold it engaged.
>
> The control cables push / pull the servo motors much like a throttle
> cable on a lawn mower. The cables are moved back and forth by a worm
> gear mechanism in the control console when the pilot rotates the roll or
> pitch
> engagement controls. Within the first few degrees of rotation, micro
> swicthes
> in the servos activate to control power to the amp (and to disengage
manual
> electric
> trim control) while the gears mesh during the last 10 to 20 degrees of
> rotation.
>
> I can see the potential problem if the engagement cables were not
positioned
> correctly and/or the cable housings were not securely clampled to the
> servos.
> In that case, the gears would not mesh properly. In fact, that was the
> major
> issue with my roll servo. The mounting screws were loose which allowed
the
> gears to slip rather that stay engaged. The service manual simply
> states to set the cables such that the gears fully mesh.
>
> There is a set-up procedure for the trim sensor which consists of
> propely centering the trim sensor on the elevator cables, but I don't
> recall any cable tension adjustments. I'll have to look at that closer.
>
> Ronnie
>
> "Jim Burns" > wrote in message
> ...
> > Congrats!!! Good for you Ronnie! It's nice to see some news about
> > something
> > actually working rather than another "my xxx is broken" :) If you've
got
> > the service manual, you may want to check the cable tensions also, from
> > what
> > I've heard, if the tension is off just a little it can cause an INOP
> > condition that is also easily solved.
> >
> > Jim
> >
> > "Ronnie" > wrote in message
> > et...
> >> I'll write more later, but I just had to report some sucess.
> >>
> >> Long story short, the old Altimatic II is now working and it
> >> works quite well. The wing lever / heading control / NAV &
> >> LOC intercept and tracking all are working great. The pitch
> >> control is working as is the altitude hold, but the altitude pre-select
> >> calibration and its ability to command the airplane to climb or descent
> >> at the correct airspeed to capture the selected altitude still needs
some
> >> adjustment. However, based on what I see so far, this should be a
simple
> >> matter of following the setup proceedure in the service manual
> >> to make the necessary adjustments.
> >>
> >> As it stands, I flew an ILS using only the autopilot controls for
> >> intercepting and tracking the localizer and for controlling pitch
> >> to stay on the glide slope. After living without an autopilot for
> >> almost 6 years, it was a great feeling to see it work. The only real
> >> issues were that the roll servo was loose in its mount allowing the
drive
> >> gears to slip and that the mechanical linkage between the pitch servo
> >> the flight controls was loose. With those items tightened up, it came
> >> to life.
> >>
> >> Fooey on me for believing the previous owner when he told me
> >> it was INOP and for not investigating it sooner.
> >>
> >> Don't disount an old autopilot as being useless just because it is old
> >> and
> >> someone elese tells you it is not worth messing with as I did for 6
> >> years.
> >> With just a little bit of effort, this one came back to life. Time
will
> >> tell how
> >> it holds up, but since it was built in 1964 and is still working, I'm
> >> hopeful
> >> it will work for a few more years.
> >>
> >> Ronnie
> >>
> >> "nobody" > wrote in message
> >> et...
> >> > Greetings:
> >> >
> >> >
> >> >
> >> > I have a Piper Altimatic II autopilot in my '64 C model Aztec which
has
> >> > been in-op since I bought the airplane. I bought a service manual
for
> >> > this autopilot with the idea of learning how it was supposed to work,
> > and
> >> > with the hope of , maybe, just maybe, getting it to work and having
it
> >> > returned to service. Yes, I know the unit is obsolete. Yes, I know
> >> > the
> >> > unit is worthless. Yes, I know that most autopilot shops say the
units
> >> > are not worth messing with. And yes,
> >> >
> >> > I'm not inclined to spend / waste much money on it.
> >> >
> >> >
> >> >
> >> > But, as an engineer and tinker, I am inclined to spend a little time
> >> > investigating. If it was good enough to be certified in the
airplane,
> > the
> >> > design once worked and it should still be able to do the job it was
> >> > designed for. I'm also inspired by a friend of mine who inherited
his
> >> > grandfather's 1947 Bonanza. He has been able to get the pneumatic
> >> > based
> >> > autopilot (yes, I do mean air controls) in that airplane working and
it
> >> > works quite well. If his pneumatic analog computer can be made to
> >> > work,
> >> > surely my germanium transistor analog computer can also be made to
> >> > work.
> >> >
> >> >
> >> >
> >> > Therefore, I'd be very interesting in getting any information such
as:
> >> >
> >> >
> >> >
> >> > - A schematic of the console amplifier. The service manual does not
> >> > include one.
> >> >
> >> >
> >> >
> >> > - Any theory of operation document for the console amplifier and/or
the
> >> > radio coupler. The service manual has a good overall theory of
> > operation
> >> > for the autopilot system, but does not go into the details for any of
> > the
> >> > electronic components.
> >> >
> >> >
> >> >
> >> > - Any old test equipment / test boxes that were designed to service
and
> >> > adjust this AP.
> >> >
> >> > The service manual lists some test boxes made by Mitchell.
> >> >
> >> >
> >> >
> >> > - Any pieces and parts of any Altimatic II, (or Autocontrol II) such
as
> >> > the RF gyros, console amplifier, control head, radio coupler,
altitude
> >> > bellows, and servos (roll, pitch, trim) that you'd like to part with.
> > If
> >> > you have any pieces and parts that might be useful for spare parts,
I'd
> >> > like to talk to you.
> >> >
> >> >
> >> >
> >> > - Leads to anyone who has experience working on these units,
including
> >> > component level repair of the electronics. I'd love to find an
> >> > experienced technician / engineer that knows these units inside and
out
> >> > and who would love to see one brought back to life.
> >> >
> >> >
> >> >
> >> > - Any "been there, done that", "been there, tried that", type of
> > stories,
> >> > positive or negative, from the group.
> >> >
> >> >
> >> >
> >> > Again, I know this is a long shot, but I'm willing to invest some
time
> > and
> >> > energy to see what can be done. As a bare minimum, I'll learn a
> >> > bunch.
> >> >
> >> >
> >> >
> >> > Thanks,
> >> >
> >> >
> >> >
> >> > Ronnie
> >> >
> >> >
> >>
> >>
> >>
> >
> >
>
>