Re: [time-nuts] GPS ceramic patch in what plastic housing?
I did a number of professional GPS installations in the 90's, mainly for Telco sync and NTP work. Where there were more than one antenna required, we used to install at different ends of the building, to minimise risk from lightning strikes etc. Rob K -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Heathkid Sent: 14 September 2010 5:30 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] GPS ceramic patch in what plastic housing? You're welcome Peter. I'm glad I was able to finally provide something useful. :) Hopefully others found it an interesting read as well. I have two Thunderbolts and am trying to figure out how far apart I should mount the antennas. Further apart reduces the changes of multpath to both antennas from the same source... but then again, placing them very close together would remove that as another in the millions of variables. Any thoughts on mounting a pair of GPS antennas to maximize "timing" accuracy? 73 Brice KA8MAV On 9/13/2010 11:34 AM, Peter Krengel wrote: > Thanks Brice for the interesting PDF! > > 73 > Peter, DG4EK > ___ > 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. ___ 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
You're welcome Peter. I'm glad I was able to finally provide something useful. :) Hopefully others found it an interesting read as well. I have two Thunderbolts and am trying to figure out how far apart I should mount the antennas. Further apart reduces the changes of multpath to both antennas from the same source... but then again, placing them very close together would remove that as another in the millions of variables. Any thoughts on mounting a pair of GPS antennas to maximize "timing" accuracy? 73 Brice KA8MAV On 9/13/2010 11:34 AM, Peter Krengel wrote: Thanks Brice for the interesting PDF! 73 Peter, DG4EK ___ 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. ___ 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.
[time-nuts] GPS ceramic patch in what plastic housing?
Thanks Brice for the interesting PDF! 73 Peter, DG4EK ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Peter, I'm not sure if you're still looking for ideas but I ran across this article which explains in a lot of detail the design of the radome for a GPS antenna: http://www.ias.ac.in/currsci/jan252006/207.pdf 73 Brice KA8MAV - Original Message - From: "Peter Krengel" To: Sent: Monday, September 06, 2010 3:04 PM Subject: [time-nuts] GPS ceramic patch in what plastic housing? Thank you all for the nice ideas. During shopping I found some interesting things. 1. disposable sparkling wine glasses made of PE (polyethelene). They are made of very thin material (just like the glass onces) and the microwave oven test leave them absolutely cold. The size is 3.8" (98mm) at the top and the height is about 3.2" (80mm). Are they too large? What would be the best size for a cone like that? 2. A shoe polish set. In a 2" (50mm) dia round plastic pot there is a removable sponge which is covered by a on top rounded cone (like a rocket noise) made of thin PE (colorless). If I remove the sponge a ceramic patch can be placed inside the pot and can be water proofed covered by that cone. Microwave test was positive, no heating. The cone material seems to be very even in thickness, its no problem to look through. I think I will try both. Peter, DG4EK ___ 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
I have perhaps a dozen dead Trimble "Bullet" antennas, allegedly done in by near-by lightning. Inside looks like the same ceramic patch as the mobile antennas, with different electronics on the back side of the "ground plane". The radome is gasketed, and the whole assembly can be disassembled and reassembled; they have TNC female connectors. $10 plus shipping, US only. They weigh nothing, so I'll see how cheaply they can ship. 73, geo - n4ua b...@lysator.liu.se wrote: On 09/05/2010 06:12 PM, Peter Krengel wrote: Hello, I just did some experiments using a ceramic patch antenna inside a small plastic (80 x 30 x 20mm) screw box and experienced much bader signals at lower elevations. The plastic is marked as PS (I guess polystyrole ?). Further experiments covering a GPS with the same kind of box seemed to effect the signals too. On the other hand covering the patch with a flat pcs of the same material didnt effect the antenna. Finding a suitable top for that gps module/patch/.. that is both the right material and the right shape is hard. Just the right shape is much easier. So: I have had good success with vacuum forming such a beast. One particular glass cup I have in the kitchen is flat top conical, of just the right size. I put it on top of the ground plane, a 1mm sheet of clear polycarbonate above that, and with an air pump and heat gun I pulled the PC down around it. A bit of white paint on the inside, and it looks really good. /Kasper Pedersen Many swedish reference stations have a snow cone made of (iirc) Plexiglass - Polymetylmetacrylic (PMMA). It should be formable using Kaspers above method. http://swepos.lmv.lm.se/stationer/hjo.htm -- Björn ___ 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. ___ 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.
[time-nuts] GPS ceramic patch in what plastic housing?
Thank you all for the nice ideas. During shopping I found some interesting things. 1. disposable sparkling wine glasses made of PE (polyethelene). They are made of very thin material (just like the glass onces) and the microwave oven test leave them absolutely cold. The size is 3.8" (98mm) at the top and the height is about 3.2" (80mm). Are they too large? What would be the best size for a cone like that? 2. A shoe polish set. In a 2" (50mm) dia round plastic pot there is a removable sponge which is covered by a on top rounded cone (like a rocket noise) made of thin PE (colorless). If I remove the sponge a ceramic patch can be placed inside the pot and can be water proofed covered by that cone. Microwave test was positive, no heating. The cone material seems to be very even in thickness, its no problem to look through. I think I will try both. Peter, DG4EK ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
> On 09/05/2010 06:12 PM, Peter Krengel wrote: >> Hello, >> >> I just did some experiments using a ceramic patch antenna inside a >> small plastic (80 x 30 x 20mm) screw box and experienced much bader >> signals at lower elevations. >> The plastic is marked as PS (I guess polystyrole ?). Further experiments >> covering a GPS with the same kind of box seemed to effect the signals >> too. On the other hand covering the patch with a flat pcs of the same >> material didnt effect the antenna. >> > > Finding a suitable top for that gps module/patch/.. that is both the > right material and the right shape is hard. Just the right shape is > much easier. So: > > I have had good success with vacuum forming such a beast. One particular > glass cup I have in the kitchen is flat top conical, of just the right > size. I put it on top of the ground plane, a 1mm sheet of > clear polycarbonate above that, and with an air pump and heat gun I > pulled the PC down around it. A bit of white paint on the inside, and > it looks really good. > > > /Kasper Pedersen Many swedish reference stations have a snow cone made of (iirc) Plexiglass - Polymetylmetacrylic (PMMA). It should be formable using Kaspers above method. http://swepos.lmv.lm.se/stationer/hjo.htm -- Björn ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
On 09/05/2010 06:12 PM, Peter Krengel wrote: > Hello, > > I just did some experiments using a ceramic patch antenna inside a > small plastic (80 x 30 x 20mm) screw box and experienced much bader signals > at lower elevations. > The plastic is marked as PS (I guess polystyrole ?). Further experiments > covering a GPS with the same kind of box seemed to effect the signals > too. On the other hand covering the patch with a flat pcs of the same > material didnt effect the antenna. > Finding a suitable top for that gps module/patch/.. that is both the right material and the right shape is hard. Just the right shape is much easier. So: I have had good success with vacuum forming such a beast. One particular glass cup I have in the kitchen is flat top conical, of just the right size. I put it on top of the ground plane, a 1mm sheet of clear polycarbonate above that, and with an air pump and heat gun I pulled the PC down around it. A bit of white paint on the inside, and it looks really good. /Kasper Pedersen ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
That lit a light bulb (pun intended), How about the cover of one of the encased low energy compact fluorescent. lamps? I've seen them in both glass and plastic (possibly PET). Robert g8rpi. --- On Mon, 6/9/10, Chuck Harris wrote: From: Chuck Harris Subject: Re: [time-nuts] GPS ceramic patch in what plastic housing? To: "Discussion of precise time and frequency measurement" Date: Monday, 6 September, 2010, 16:38 I know, cut the top off of a 150W incandescent light bulb and use it to make a radome. -Chuck Harris jimlux wrote: > Predrag Dukic wrote: >> >> Bill, >> >> Pyrex ( and any other glass) could reflect too much. It is true that >> glass, >> >> depending on composition, is not absorbing microwaves, and does not >> heat itself in the owen, >> >> but how much it is transparent at 2.4 ghz should be checked somehow... >> >> P. Dukic >> >> >> > > I wouldn't use a glass jar/mixing bowl, what-have-you. > > A) glass is a bit lossy (even at 100-200kHz), but probably not enough to > be an issue.. (Now, if you were building kW scale capacitors for a tesla > coil, that's a different thing) > > B) A bigger problem: Glass has a (unevenly controlled) dielectric > constant of around 2.5.. > > So, you'll get reflections at both interfaces as well as some refraction > as the signal passes through the "radome" > > The whole radome design thing is much trickier than one might think for > a something where angle of incidence is important. There's a reason that > you see lots of hemispheres, and one tries to control the thickness of > the radome (in fact, sometimes, you make the shell from a honeycomb core > with 2 face sheets, although at L band, this would be tricky). > > So, either you use something simple, and accept whatever defects it > creates in your antenna pattern, or get fancy. > > Glass babyfood or canning jars will probably work, and will literally > last your life time. White painted plastic would also work. > > Watch out for things like appropriately venting it (so moisture doesn't > collect inside) and making sure it doesn't make a little solar oven > (gotta paint that clear glass, I suspect) > > ___ > 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. > ___ 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
I know, cut the top off of a 150W incandescent light bulb and use it to make a radome. -Chuck Harris jimlux wrote: Predrag Dukic wrote: Bill, Pyrex ( and any other glass) could reflect too much. It is true that glass, depending on composition, is not absorbing microwaves, and does not heat itself in the owen, but how much it is transparent at 2.4 ghz should be checked somehow... P. Dukic I wouldn't use a glass jar/mixing bowl, what-have-you. A) glass is a bit lossy (even at 100-200kHz), but probably not enough to be an issue.. (Now, if you were building kW scale capacitors for a tesla coil, that's a different thing) B) A bigger problem: Glass has a (unevenly controlled) dielectric constant of around 2.5.. So, you'll get reflections at both interfaces as well as some refraction as the signal passes through the "radome" The whole radome design thing is much trickier than one might think for a something where angle of incidence is important. There's a reason that you see lots of hemispheres, and one tries to control the thickness of the radome (in fact, sometimes, you make the shell from a honeycomb core with 2 face sheets, although at L band, this would be tricky). So, either you use something simple, and accept whatever defects it creates in your antenna pattern, or get fancy. Glass babyfood or canning jars will probably work, and will literally last your life time. White painted plastic would also work. Watch out for things like appropriately venting it (so moisture doesn't collect inside) and making sure it doesn't make a little solar oven (gotta paint that clear glass, I suspect) ___ 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Predrag Dukic wrote: Bill, Pyrex ( and any other glass) could reflect too much. It is true that glass, depending on composition, is not absorbing microwaves, and does not heat itself in the owen, but how much it is transparent at 2.4 ghz should be checked somehow... P. Dukic I wouldn't use a glass jar/mixing bowl, what-have-you. A) glass is a bit lossy (even at 100-200kHz), but probably not enough to be an issue.. (Now, if you were building kW scale capacitors for a tesla coil, that's a different thing) B) A bigger problem: Glass has a (unevenly controlled) dielectric constant of around 2.5.. So, you'll get reflections at both interfaces as well as some refraction as the signal passes through the "radome" The whole radome design thing is much trickier than one might think for a something where angle of incidence is important. There's a reason that you see lots of hemispheres, and one tries to control the thickness of the radome (in fact, sometimes, you make the shell from a honeycomb core with 2 face sheets, although at L band, this would be tricky). So, either you use something simple, and accept whatever defects it creates in your antenna pattern, or get fancy. Glass babyfood or canning jars will probably work, and will literally last your life time. White painted plastic would also work. Watch out for things like appropriately venting it (so moisture doesn't collect inside) and making sure it doesn't make a little solar oven (gotta paint that clear glass, I suspect) ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Bill, Pyrex ( and any other glass) could reflect too much. It is true that glass, depending on composition, is not absorbing microwaves, and does not heat itself in the owen, but how much it is transparent at 2.4 ghz should be checked somehow... P. Dukic At 00:55 6.9.2010, you wrote: Hi Peter, While you did not say, I am going to guess you are considering making a weather proof (or nearly so) housing for your ceramic patch antenna. I have used the little patch antennas with the magnetic base from Motorola for the top of my car. They seem to last quite long as the one I have has been out in the elements (San Diego, CA) for around 9 or ten years. Yes, its plastic housing is showing some discoloration from the UV rays, but no operational issues. However, for a housing, may I suggest a small PYREX glass mixing bowl. It is a little heavy but very sturdy and some have an edge that could be used to hold it in place by fitting a collar around it made out of wood that would get clamped to the base which could be made out of wood. The wood would have to be varnished with a good Urethane. Anyway, my two cents; BillWB6BNQ Magnus Danielson wrote: > On 09/05/2010 10:06 PM, Peter Krengel wrote: > > Thanks Robert, Stanley and Bob for the tips. > > > > I tested some materials in a microwave oven and they all seemed to > > be good because there was no heating (maybe handwarm at 800W). > > > > So the magic word seems to be refracting effects even at 1.5GHz... > > > > As I cannot get a commercial helf sphere for putting over the patch > > has anyone an idea what to take for i.e. from kitchen? > > One should recall that some plastics absorb more water than others... so > unless one has a good info on their absorbtion, putting them into water > overnight and the pour it out and wipe it clean just prior to microwave > it would form a better simulation... > > Cheers, > Magnus > > ___ > 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. ___ 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Good point Chuck, Finding jars these days that are made out of glass is becoming a thing of the past. So many things are going plastic. BillWB6BNQ Chuck Harris wrote: > Why go to that much trouble. An old pickle jar would probably do just as > well. > > -Chuck Harris > > WB6BNQ wrote: > > Hi Peter, > > > > While you did not say, I am going to guess you are considering making a > > weather > > proof (or nearly so) housing for your ceramic patch antenna. I have used > > the > > little patch antennas with the magnetic base from Motorola for the top of my > > car. They seem to last quite long as the one I have has been out in the > > elements > > (San Diego, CA) for around 9 or ten years. Yes, its plastic housing is > > showing > > some discoloration from the UV rays, but no operational issues. > > > > However, for a housing, may I suggest a small PYREX glass mixing bowl. It > > is a > > little heavy but very sturdy and some have an edge that could be used to > > hold it > > in place by fitting a collar around it made out of wood that would get > > clamped to > > the base which could be made out of wood. The wood would have to be > > varnished > > with a good Urethane. > > > > Anyway, my two cents; > > > > BillWB6BNQ > > ___ > 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Why go to that much trouble. An old pickle jar would probably do just as well. -Chuck Harris WB6BNQ wrote: Hi Peter, While you did not say, I am going to guess you are considering making a weather proof (or nearly so) housing for your ceramic patch antenna. I have used the little patch antennas with the magnetic base from Motorola for the top of my car. They seem to last quite long as the one I have has been out in the elements (San Diego, CA) for around 9 or ten years. Yes, its plastic housing is showing some discoloration from the UV rays, but no operational issues. However, for a housing, may I suggest a small PYREX glass mixing bowl. It is a little heavy but very sturdy and some have an edge that could be used to hold it in place by fitting a collar around it made out of wood that would get clamped to the base which could be made out of wood. The wood would have to be varnished with a good Urethane. Anyway, my two cents; BillWB6BNQ ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Hi Peter, While you did not say, I am going to guess you are considering making a weather proof (or nearly so) housing for your ceramic patch antenna. I have used the little patch antennas with the magnetic base from Motorola for the top of my car. They seem to last quite long as the one I have has been out in the elements (San Diego, CA) for around 9 or ten years. Yes, its plastic housing is showing some discoloration from the UV rays, but no operational issues. However, for a housing, may I suggest a small PYREX glass mixing bowl. It is a little heavy but very sturdy and some have an edge that could be used to hold it in place by fitting a collar around it made out of wood that would get clamped to the base which could be made out of wood. The wood would have to be varnished with a good Urethane. Anyway, my two cents; BillWB6BNQ Magnus Danielson wrote: > On 09/05/2010 10:06 PM, Peter Krengel wrote: > > Thanks Robert, Stanley and Bob for the tips. > > > > I tested some materials in a microwave oven and they all seemed to > > be good because there was no heating (maybe handwarm at 800W). > > > > So the magic word seems to be refracting effects even at 1.5GHz... > > > > As I cannot get a commercial helf sphere for putting over the patch > > has anyone an idea what to take for i.e. from kitchen? > > One should recall that some plastics absorb more water than others... so > unless one has a good info on their absorbtion, putting them into water > overnight and the pour it out and wipe it clean just prior to microwave > it would form a better simulation... > > Cheers, > Magnus > > ___ > 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Hi Plastic salad bowls might do ok. More or less it's an adventure trip to the local kitchen stuff store. Bob On Sep 5, 2010, at 4:06 PM, "Peter Krengel" wrote: > Thanks Robert, Stanley and Bob for the tips. > > I tested some materials in a microwave oven and they all seemed to > be good because there was no heating (maybe handwarm at 800W). > > So the magic word seems to be refracting effects even at 1.5GHz... > > As I cannot get a commercial helf sphere for putting over the patch > has anyone an idea what to take for i.e. from kitchen? > > Peter > DG4EK > ___ > 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. > ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
On 09/05/2010 10:06 PM, Peter Krengel wrote: Thanks Robert, Stanley and Bob for the tips. I tested some materials in a microwave oven and they all seemed to be good because there was no heating (maybe handwarm at 800W). So the magic word seems to be refracting effects even at 1.5GHz... As I cannot get a commercial helf sphere for putting over the patch has anyone an idea what to take for i.e. from kitchen? One should recall that some plastics absorb more water than others... so unless one has a good info on their absorbtion, putting them into water overnight and the pour it out and wipe it clean just prior to microwave it would form a better simulation... Cheers, Magnus ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
I would try a search for cake pans in the archive. Large funnel inverted to cover. http://www.mail-archive.com/time-nuts@febo.com/msg27517.html http://www.mail-archive.com/time-nuts@febo.com/msg27561.html Stanley - Original Message From: Peter Krengel To: time-nuts@febo.com Sent: Sun, September 5, 2010 3:06:26 PM Subject: [time-nuts] GPS ceramic patch in what plastic housing? Thanks Robert, Stanley and Bob for the tips. I tested some materials in a microwave oven and they all seemed to be good because there was no heating (maybe handwarm at 800W). So the magic word seems to be refracting effects even at 1.5GHz... As I cannot get a commercial helf sphere for putting over the patch has anyone an idea what to take for i.e. from kitchen? Peter DG4EK ___ 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. ___ 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.
[time-nuts] GPS ceramic patch in what plastic housing?
Thanks Robert, Stanley and Bob for the tips. I tested some materials in a microwave oven and they all seemed to be good because there was no heating (maybe handwarm at 800W). So the magic word seems to be refracting effects even at 1.5GHz... As I cannot get a commercial helf sphere for putting over the patch has anyone an idea what to take for i.e. from kitchen? Peter DG4EK ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Hi What are you trying to achieve ? If you are looking for a simple cover for the patch, the microwave oven is your friend. Anything that heats up in a microwave is a bad idea, unless it's thin. Most materials with a variable cross section will act as a lens to some extent. Bob On Sep 5, 2010, at 12:12 PM, "Peter Krengel" wrote: > Hello, > > I just did some experiments using a ceramic patch antenna inside a > small plastic (80 x 30 x 20mm) screw box and experienced much bader signals > at lower elevations. > The plastic is marked as PS (I guess polystyrole ?). Further experiments > covering a GPS with the same kind of box seemed to effect the signals > too. On the other hand covering the patch with a flat pcs of the same > material didnt effect the antenna. > > Is there possibly a cavity effect? > > What to take best? > > Any ideas? > > > Thank you > > Peter, DG4EK > ___ > 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. > ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
The plastic may also function as a lens particularly the corners of the box see: http://authors.library.caltech.edu/10409/1/ZMUieeetmtt92.pdf figure 2 shows a polyethylene lens. Stanley - Original Message From: Peter Krengel To: time-nuts@febo.com Sent: Sun, September 5, 2010 11:12:05 AM Subject: [time-nuts] GPS ceramic patch in what plastic housing? Hello, I just did some experiments using a ceramic patch antenna inside a small plastic (80 x 30 x 20mm) screw box and experienced much bader signals at lower elevations. The plastic is marked as PS (I guess polystyrole ?). Further experiments covering a GPS with the same kind of box seemed to effect the signals too. On the other hand covering the patch with a flat pcs of the same material didnt effect the antenna. Is there possibly a cavity effect? What to take best? Any ideas? Thank you Peter, DG4EK ___ 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Test the box minus the screws in a microwave oven if the material heats up then it is not transparent. May not be the plastic but a pigment that was added to give the box it's color. Stanley - Original Message From: Peter Krengel To: time-nuts@febo.com Sent: Sun, September 5, 2010 11:12:05 AM Subject: [time-nuts] GPS ceramic patch in what plastic housing? Hello, I just did some experiments using a ceramic patch antenna inside a small plastic (80 x 30 x 20mm) screw box and experienced much bader signals at lower elevations. The plastic is marked as PS (I guess polystyrole ?). Further experiments covering a GPS with the same kind of box seemed to effect the signals too. On the other hand covering the patch with a flat pcs of the same material didnt effect the antenna. Is there possibly a cavity effect? What to take best? Any ideas? Thank you Peter, DG4EK ___ 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. ___ 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.
Re: [time-nuts] GPS ceramic patch in what plastic housing?
Hi Peter, Sounds like refraction. The plastic has more effect at lower angles. Robert G8RPI --- On Sun, 5/9/10, Peter Krengel wrote: From: Peter Krengel Subject: [time-nuts] GPS ceramic patch in what plastic housing? To: time-nuts@febo.com Date: Sunday, 5 September, 2010, 17:12 Hello, I just did some experiments using a ceramic patch antenna inside a small plastic (80 x 30 x 20mm) screw box and experienced much bader signals at lower elevations. The plastic is marked as PS (I guess polystyrole ?). Further experiments covering a GPS with the same kind of box seemed to effect the signals too. On the other hand covering the patch with a flat pcs of the same material didnt effect the antenna. Is there possibly a cavity effect? What to take best? Any ideas? Thank you Peter, DG4EK ___ 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. ___ 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.
[time-nuts] GPS ceramic patch in what plastic housing?
Hello, I just did some experiments using a ceramic patch antenna inside a small plastic (80 x 30 x 20mm) screw box and experienced much bader signals at lower elevations. The plastic is marked as PS (I guess polystyrole ?). Further experiments covering a GPS with the same kind of box seemed to effect the signals too. On the other hand covering the patch with a flat pcs of the same material didnt effect the antenna. Is there possibly a cavity effect? What to take best? Any ideas? Thank you Peter, DG4EK ___ 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.
