John & Juan:
Your EMI problems certainly do present considerable difficulties. Your suggestions of placing connectors on multiple faces of a module run counter to the whole module mounting plan for Eagle. The modules are mounted with only about 1.5mm clearance at the flanges and only about 16mm clearance on the sides. The "rear end" of the module is also difficult as there is just not that much space for cabling and connector access. Mechanical designers in the past have been raked over the coals for not providing sufficient connector access. The curren plan allows about 100mm (I don't have the drawings with me at the moment) of space between facing columns of modules for the cabling and connector access. This is a plan that is pretty basic to the whole wiring plan for Eagle, and it is a result of a lot of experience with P3D.
While the basic module design for Eagle, unlike P3D, does not provide for the stacking of modules, a small CAN module placed on top of the URx, could be considered. Wiring to this sub-module would be by means of jumper leads from its connector face into the URx.
I caution that there currently is not planned for much space above the rows of modules as the current spaceframe plan has the modules placed fairly closely under the solar panels. This concept is part of the need to keep the mass moment of inertia, Izz, high. This is NOT just a desirable feature, but a necessary, MUST need for the spin stability of the spacecraft. So any top-mounted sub-module would have to not be very thick.
All of these issues arise from the practical considerations of the overall mission of the spacecraft. Unfortunately for the EMI and other "local" issues, we cannot design the spaceframe only for EMI, but must solve other mission requirements, too.
I am not trying to be unmovable on the design if the URx, but I am trying to explain how we can have a successful mission.
'73, Dick, KD1K
Good morning Dick,
I agree that everything needs to be in one enclosure if at all humanly possible, but the front panel is badly blocked by the CAN-Do circuit board. There just isn't enough room remaining to squeeze in the 4 SMA connectors that are required for this receiver.
And if we need to go to a two-compartment enclosure configuration to isolate the CAN-Do EMI from the analog receiver, running those four RF lines in the back side of the CAN-Do compartment, and out the front is an awkward design. Can you squeeze the four SMA connectors out the side if the interconnecting cables are right angle style? That would allow all the RF to stay well clear of the CAN-Do EMI.
Juan
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Saturday, June 30, 2007 6:33 AM To: [email protected] Subject: [eagle] Mocule Connectors
John & Juan:
Your EMI problems certainly do present considerable difficulties. Your suggestions of placing connectors on multiple faces of a module run counter to the whole module mounting plan for Eagle. The modules are mounted with only about 1.5mm clearance at the flanges and only about 16mm clearance on the sides. The "rear end" of the module is also difficult as there is just not that much space for cabling and connector access. Mechanical designers in the past have been raked over the coals for not providing sufficient connector access. The curren plan allows about 100mm (I don't have the drawings with me at the moment) of space between facing columns of modules for the cabling and connector access. This is a plan that is pretty basic to the whole wiring plan for Eagle, and it is a result of a lot of experience with P3D.
While the basic module design for Eagle, unlike P3D, does not provide for the stacking of modules, a small CAN module placed on top of the URx, could be considered. Wiring to this sub-module would be by means of jumper leads from its connector face into the URx.
I caution that there currently is not planned for much space above the rows of modules as the current spaceframe plan has the modules placed fairly closely under the solar panels. This concept is part of the need to keep the mass moment of inertia, Izz, high. This is NOT just a desirable feature, but a necessary, MUST need for the spin stability of the spacecraft. So any top-mounted sub-module would have to not be very thick.
All of these issues arise from the practical considerations of the overall mission of the spacecraft. Unfortunately for the EMI and other "local" issues, we cannot design the spaceframe only for EMI, but must solve other mission requirements, too.
I am not trying to be unmovable on the design if the URx, but I am trying to explain how we can have a successful mission.
'73, Dick, KD1K _______________________________________________ Via the Eagle mailing list courtesy of AMSAT-NA [email protected] http://amsat.org/mailman/listinfo/eagle
Juan:
There just plain is not enough access on the sides of the module to make a connection to the SMA connectors, no withstanding that the aluminum cover would not be able to provide a mounting surface. It would also be some pretty ugly gymnastics with the cover in such a situation. I am sure that you can get four SMA connectors if you don't insist on their being PCB mounted. (I need to look again at John's drawings which are not with me at the moment.)
Take a look at my idea of a small cannister on top of the module with the CAN module inside.
'73, Dick, KD1K
----- Original Message ----- From: Juan Rivera [email protected] Date: Saturday, June 30, 2007 9:48 am Subject: RE: [eagle] Module Connectors To: [email protected], [email protected]
Good morning Dick,
I agree that everything needs to be in one enclosure if at all humanly possible, but the front panel is badly blocked by the CAN-Do circuit board. There just isn't enough room remaining to squeeze in the 4 SMA connectorsthat are required for this receiver.
And if we need to go to a two-compartment enclosure configuration to isolate the CAN-Do EMI from the analog receiver, running those four RF lines in the back side of the CAN-Do compartment, and out the front is an awkward design. Can you squeeze the four SMA connectors out the side if the interconnectingcables are right angle style? That would allow all the RF to stay well clear of the CAN-Do EMI.
Juan
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Saturday, June 30, 2007 6:33 AM To: [email protected] Subject: [eagle] Mocule Connectors
John & Juan:
Your EMI problems certainly do present considerable difficulties. Your suggestions of placing connectors on multiple faces of a module run counter to the whole module mounting plan for Eagle. The modules are mounted with only about 1.5mm clearance at the flanges and only about 16mm clearance on the sides. The "rear end" of the module is also difficult as there is just not that much space for cabling and connector access. Mechanical designers in the past have been raked over the coals for not providing sufficient connector access. The curren plan allows about 100mm (I don't have the drawings with me at the moment) of space between facing columns of modules for the cabling and connector access. This is a plan that is pretty basic to the whole wiring plan for Eagle, and it is a result of a lot of experience with P3D.
While the basic module design for Eagle, unlike P3D, does not provide for the stacking of modules, a small CAN module placed on top of the URx, could be considered. Wiring to this sub-module would be by means of jumper leads from its connector face into the URx.
I caution that there currently is not planned for much space above the rows of modules as the current spaceframe plan has the modules placed fairly closely under the solar panels. This concept is part of the need to keep the mass moment of inertia, Izz, high. This is NOT just a desirable feature, but a necessary, MUST need for the spin stability of the spacecraft. So any top-mounted sub-module would have to not be very thick.
All of these issues arise from the practical considerations of the overall mission of the spacecraft. Unfortunately for the EMI and other "local" issues, we cannot design the spaceframe only for EMI, but must solve other mission requirements, too.
I am not trying to be unmovable on the design if the URx, but I am trying to explain how we can have a successful mission.
'73, Dick, KD1K _______________________________________________ Via the Eagle mailing list courtesy of AMSAT-NA [email protected] http://amsat.org/mailman/listinfo/eagle
Dick,
Following up on my reply, here's a shot of a right angle SMA connected to the type of PCB mount connectors we're using:
This happens to be a straight cable-mount SMA connected to a right angle adapter, but the size is the same either way. It looks like we'll need about 25 mm of space on the side of the module to get the four RF signals in and out.
73,
Juan - WA6HTP
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Saturday, June 30, 2007 6:33 AM To: [email protected] Subject: [eagle] Mocule Connectors
John & Juan:
Your EMI problems certainly do present considerable difficulties. Your
suggestions of placing connectors on multiple faces of a module run
counter to the whole module mounting plan for Eagle. The modules are
mounted with only about 1.5mm clearance at the flanges and only about
16mm clearance on the sides. The "rear end" of the module is also
difficult as there is just not that much space for cabling and
connector access. Mechanical designers in the past have been raked over
the coals for not providing sufficient connector access. The curren
plan allows about 100mm (I don't have the drawings with me at the
moment) of space between facing columns of modules for the cabling and
connector access. This is a plan that is pretty basic to the whole
wiring plan for Eagle, and it is a result of a lot of experience with
P3D.
While the basic module design for Eagle, unlike P3D, does not provide
for the stacking of modules, a small CAN module placed on top of the
URx, could be considered. Wiring to this sub-module would be by means
of jumper leads from its connector face into the URx.
I caution that there currently is not planned for much space above the
rows of modules as the current spaceframe plan has the modules placed
fairly closely under the solar panels. This concept is part of the need
to keep the mass moment of inertia, Izz, high. This is NOT just a
desirable feature, but a necessary, MUST need for the spin stability of
the spacecraft. So any top-mounted sub-module would have to not be very
thick.
All of these issues arise from the practical considerations of the
overall mission of the spacecraft. Unfortunately for the EMI and
other "local" issues, we cannot design the spaceframe only for EMI, but
must solve other mission requirements, too.
I am not trying to be unmovable on the design if the URx, but I am
trying to explain how we can have a successful mission.
'73,
Dick, KD1K
_______________________________________________
Via the Eagle mailing list courtesy of AMSAT-NA
Juan:
What do you propose to do with the cover?
Dick
----- Original Message ----- From: Juan Rivera [email protected] Date: Saturday, June 30, 2007 10:42 am Subject: RE: [eagle] Module Connectors To: [email protected], [email protected]
Dick,
Following up on my reply, here's a shot of a right angle SMA connected to the type of PCB mount connectors we're using:
This happens to be a straight cable-mount SMA connected to a right angleadapter, but the size is the same either way. It looks like we'll need about 25 mm of space on the side of the module to get the four RF signals in and out.
73,
Juan - WA6HTP
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Saturday, June 30, 2007 6:33 AM To: [email protected] Subject: [eagle] Mocule Connectors
John & Juan:
Your EMI problems certainly do present considerable difficulties. Your
suggestions of placing connectors on multiple faces of a module run
counter to the whole module mounting plan for Eagle. The modules are
mounted with only about 1.5mm clearance at the flanges and only about
16mm clearance on the sides. The "rear end" of the module is also
difficult as there is just not that much space for cabling and
connector access. Mechanical designers in the past have been raked over
the coals for not providing sufficient connector access. The curren
plan allows about 100mm (I don't have the drawings with me at the
moment) of space between facing columns of modules for the cabling and
connector access. This is a plan that is pretty basic to the whole
wiring plan for Eagle, and it is a result of a lot of experience with
P3D.
While the basic module design for Eagle, unlike P3D, does not provide
for the stacking of modules, a small CAN module placed on top of the
URx, could be considered. Wiring to this sub-module would be by means
of jumper leads from its connector face into the URx.
I caution that there currently is not planned for much space above the
rows of modules as the current spaceframe plan has the modules placed
fairly closely under the solar panels. This concept is part of the need
to keep the mass moment of inertia, Izz, high. This is NOT just a
desirable feature, but a necessary, MUST need for the spin stability of
the spacecraft. So any top-mounted sub-module would have to not be very
thick.
All of these issues arise from the practical considerations of the
overall mission of the spacecraft. Unfortunately for the EMI and
other "local" issues, we cannot design the spaceframe only for EMI, but
must solve other mission requirements, too.
I am not trying to be unmovable on the design if the URx, but I am
trying to explain how we can have a successful mission.
'73,
Dick, KD1K
Via the Eagle mailing list courtesy of AMSAT-NA
participants (2)
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Juan Rivera -
rjansson＠cfl.rr.com