Small transmitter antenna

[Gareth Magennis]

OK, so I have one of these to repair, which is missing the "tail" antenna on
the transmitter.

http://www.samsontech.com/samson/products/wireless-systems/airline/airline-ag1/



Now I know very little about RF, antennae etc.
I can't get a replacement antenna for this, so how feasible would it be to
make one?

I assume this will be a fine coil of wire covered in rubber, e.g. a tiny
rubber ducky?

Or could you just attach a long wire and roll/pack it up and attach the blob
to the guitar/guitarist?



Cheers,


Gareth.

 

[Pat]

On Wed, 21 Feb 2018 18:37:08 -0000, "Gareth Magennis"
<soundserviceleeds@outlook.com> wrote:

OK, so I have one of these to repair, which is missing the "tail" antenna on
the transmitter.

http://www.samsontech.com/samson/products/wireless-systems/airline/airline-ag1/



Now I know very little about RF, antennae etc.
I can't get a replacement antenna for this, so how feasible would it be to
make one?

I assume this will be a fine coil of wire covered in rubber, e.g. a tiny
rubber ducky?

Or could you just attach a long wire and roll/pack it up and attach the blob
to the guitar/guitarist?



Cheers,


Gareth.

Rather than the "fine coil of wire" you mentioned, it is likely just a
piece of wire. The length should be the about the same as the
original. The length would be similar to the length of the antennas
on the base unit.

 

[Ralph Mowery]

In article <p%ijC.119756$3X6.90914@fx22.am4>,
soundserviceleeds@outlook.com says...

OK, so I have one of these to repair, which is missing the "tail" antenna on
the transmitter.

http://www.samsontech.com/samson/products/wireless-systems/airline/airline-ag1/



Now I know very little about RF, antennae etc.
I can't get a replacement antenna for this, so how feasible would it be to
make one?

I assume this will be a fine coil of wire covered in rubber, e.g. a tiny
rubber ducky?

Or could you just attach a long wire and roll/pack it up and attach the blob
to the guitar/guitarist?

It would help to know the frequency range this operates on. Looks to be
about 6 inches of wire. If it is operating close to 450 MHz, then about
6 inches of wire is all that is needed. Measure the antenna on the
receiver and use a piece of wire that long.

 

[Gareth Magennis]

"Ralph Mowery" wrote in message
news:MPG.34f78e223f99e335989723@news.east.earthlink.net...

In article <p%ijC.119756$3X6.90914@fx22.am4>,
soundserviceleeds@outlook.com says...

OK, so I have one of these to repair, which is missing the "tail" antenna
on
the transmitter.

http://www.samsontech.com/samson/products/wireless-systems/airline/airline-ag1/



Now I know very little about RF, antennae etc.
I can't get a replacement antenna for this, so how feasible would it be to
make one?

I assume this will be a fine coil of wire covered in rubber, e.g. a tiny
rubber ducky?

Or could you just attach a long wire and roll/pack it up and attach the
blob
to the guitar/guitarist?

It would help to know the frequency range this operates on. Looks to be
about 6 inches of wire. If it is operating close to 450 MHz, then about
6 inches of wire is all that is needed. Measure the antenna on the
receiver and use a piece of wire that long.


*************************************



From the manual:

It operates in the uncrowded 801 – 805, 863 – 865 MHz UHF frequency range



Gareth.

 

[Ralph Mowery]

In article <lEjjC.376107$Nt6.128804@fx43.am4>,
soundserviceleeds@outlook.com says...

It would help to know the frequency range this operates on. Looks to be
about 6 inches of wire. If it is operating close to 450 MHz, then about
6 inches of wire is all that is needed. Measure the antenna on the
receiver and use a piece of wire that long.


*************************************



From the manual:

It operates in the uncrowded 801 ? 805, 863 ? 865 MHz UHF frequency range

In that case the antenna should be about 3 1/4 to 3 1/2 inches long. If
you are using wire that is insulated, just make it 3 1/4 inches.

That is probably close to the origional length.

That makes it a 1/4 of an electrical wavelength long.

For a low power short range piece of equipment, I doubt it makes much
difference on how long it is, from 3 inchs to a foot long.

 

[Gareth Magennis]

"Ralph Mowery" wrote in message
news:MPG.34f7974b46a65bc0989724@news.east.earthlink.net...

In article <lEjjC.376107$Nt6.128804@fx43.am4>,
soundserviceleeds@outlook.com says...

It would help to know the frequency range this operates on. Looks to be
about 6 inches of wire. If it is operating close to 450 MHz, then about
6 inches of wire is all that is needed. Measure the antenna on the
receiver and use a piece of wire that long.


*************************************



From the manual:

It operates in the uncrowded 801 ? 805, 863 ? 865 MHz UHF frequency range

In that case the antenna should be about 3 1/4 to 3 1/2 inches long. If
you are using wire that is insulated, just make it 3 1/4 inches.

That is probably close to the origional length.

That makes it a 1/4 of an electrical wavelength long.

For a low power short range piece of equipment, I doubt it makes much
difference on how long it is, from 3 inchs to a foot long.



******************************************


OK, so the "antenna" is just a piece of wire then.


Blimey.


Gareth.

 

[Gareth Magennis]

"Ralph Mowery" wrote in message
news:MPG.34f7974b46a65bc0989724@news.east.earthlink.net...

In article <lEjjC.376107$Nt6.128804@fx43.am4>,
soundserviceleeds@outlook.com says...

It would help to know the frequency range this operates on. Looks to be
about 6 inches of wire. If it is operating close to 450 MHz, then about
6 inches of wire is all that is needed. Measure the antenna on the
receiver and use a piece of wire that long.


*************************************



From the manual:

It operates in the uncrowded 801 ? 805, 863 ? 865 MHz UHF frequency range

In that case the antenna should be about 3 1/4 to 3 1/2 inches long. If
you are using wire that is insulated, just make it 3 1/4 inches.

That is probably close to the origional length.

That makes it a 1/4 of an electrical wavelength long.

For a low power short range piece of equipment, I doubt it makes much
difference on how long it is, from 3 inchs to a foot long.



**********************************


Thanks, Ralph, you have made my day.

I thought it was much more complicated than a piece of wire.


Gareth.

 

[Terry Schwartz]

It can be, this is a topic that of late is near and dear to my career.

Antennas are a science to themselves. Any piece of wire can be an antenna, but if you want efficiency and range, things get a *lot* more complicated quickly.

It's far too broad a topic to cover here, and there is plenty written about it on the web (not all of which is correct). It's safe to say that for your application, a hunk of wire is sufficient.

Terry

Thanks, Ralph, you have made my day.

I thought it was much more complicated than a piece of wire.


Gareth.

 

[Tim R]

But a yagi would be fun.

 

[Mike Coon]

In article <62ca1da1-31f4-472f-aea6-cb046149a661@googlegroups.com>,
timothy42b@aol.com says...

But a yagi would be fun.

Good exercise, you could say...

Mike.

 

[Ralph Mowery]

In article <FvkjC.177164$t77.70928@fx29.am4>,
soundserviceleeds@outlook.com says...

It operates in the uncrowded 801 ? 805, 863 ? 865 MHz UHF frequency range





In that case the antenna should be about 3 1/4 to 3 1/2 inches long. If
you are using wire that is insulated, just make it 3 1/4 inches.

That is probably close to the origional length.

That makes it a 1/4 of an electrical wavelength long.

For a low power short range piece of equipment, I doubt it makes much
difference on how long it is, from 3 inchs to a foot long.



**********************************


Thanks, Ralph, you have made my day.

I thought it was much more complicated than a piece of wire.

Simple antennas are not that complicated. Juat a piece of wire 1/4 of a
wavelength long should work fine for that application.

When you get much below 450 MHz and want an antenna shorter than around
6 inches is when it will get somewhat complicated . Then they look like
a spring under the insulation.

There is a number around 234 that if you devide it by the frequency in
MHz you will get the length of a simple 1/4 wave antenna.

 

[Phil Allison]

Gareth Magennis wrote:

----------------------

OK, so I have one of these to repair, which is missing the "tail" antenna on
the transmitter.

http://www.samsontech.com/samson/products/wireless-systems/airline/airline-ag1/


Now I know very little about RF, antennae etc.
I can't get a replacement antenna for this, so how feasible would it be to
make one?

I assume this will be a fine coil of wire covered in rubber, e.g. a tiny
rubber ducky?

** While possible, it is just as likely to be a simple 1/4 wave whip.

Or could you just attach a long wire and roll/pack it up and attach the blob
to the guitar/guitarist?

** Err- no.


..... Phil

 

[Phil Allison]

Gareth Magennis wrote:

----------------------

From the manual:

It operates in the uncrowded 801 – 805, 863 – 865 MHz UHF frequency range

** Normally a straight, 1/4 wave length whip antenna does the job well. Helically wound antennas (rubber duckies) are not better, only shorter and less efficient. I note the owners manual says the antennas are 1/4 wave.

RF travels at 300,000 km/S so 830 MHz has a wavelength of 360mm, 25% of which gives you 90mm from the attachment point inside the Tx. A 5% "end correction" can be applied so make it 85mm.

Use wire that has a stiff cover like Teflon, to hold it out straight.



.... Phil

 

[gregz]

Ralph Mowery <rmowery28146@earthlink.net> wrote:

In article <lEjjC.376107$Nt6.128804@fx43.am4>,
soundserviceleeds@outlook.com says...

It would help to know the frequency range this operates on. Looks to be
about 6 inches of wire. If it is operating close to 450 MHz, then about
6 inches of wire is all that is needed. Measure the antenna on the
receiver and use a piece of wire that long.


*************************************



From the manual:

It operates in the uncrowded 801 ? 805, 863 ? 865 MHz UHF frequency range





In that case the antenna should be about 3 1/4 to 3 1/2 inches long. If
you are using wire that is insulated, just make it 3 1/4 inches.

That is probably close to the origional length.

That makes it a 1/4 of an electrical wavelength long.

For a low power short range piece of equipment, I doubt it makes much
difference on how long it is, from 3 inchs to a foot long.

It could be a coaxial type full wave.

Greg

 

[Gareth Magennis]

"Gareth Magennis" wrote in message news%ijC.119756$3X6.90914@fx22.am4...

OK, so I have one of these to repair, which is missing the "tail" antenna on
the transmitter.

http://www.samsontech.com/samson/products/wireless-systems/airline/airline-ag1/



Now I know very little about RF, antennae etc.
I can't get a replacement antenna for this, so how feasible would it be to
make one?

I assume this will be a fine coil of wire covered in rubber, e.g. a tiny
rubber ducky?

Or could you just attach a long wire and roll/pack it up and attach the blob
to the guitar/guitarist?



Cheers,


Gareth.



****************************************


Well a piece of wire worked a treat.

With a bit of heatshrink for strain relief at the transmitter end and
another on the end of the tail, it even looks like a proper one.


Thanks to all for the calculations and info.



Cheers,


Gareth.

 

[Phil Allison]

Gareth Magennis wrote:

-----------------------

Well a piece of wire worked a treat.

With a bit of heatshrink for strain relief at the transmitter end and
another on the end of the tail, it even looks like a proper one.

** So now you know how to make a "rat tail" antenna.

Thanks to all for the calculations and info.

** 300 / MHz = wavelength in metres, is worth remembering.


FYI:

That AG-1 unit is about as basic as UHF FM links get, so has limited useful range and is prone to signal drops out due to multipath interference. The Tx signal can almost cancel itself after reflecting off objects and surfaces and then arriving at the Rx.

Better models have twin channel receivers, with two separated antennas, operating as a diversity pair that helps greatly to eliminate such drop outs.



..... Phil

 

[gregz]

gregz <zekor@comcast.net> wrote:

Ralph Mowery <rmowery28146@earthlink.net> wrote:
In article <lEjjC.376107$Nt6.128804@fx43.am4>,
soundserviceleeds@outlook.com says...

It would help to know the frequency range this operates on. Looks to be
about 6 inches of wire. If it is operating close to 450 MHz, then about
6 inches of wire is all that is needed. Measure the antenna on the
receiver and use a piece of wire that long.


*************************************



From the manual:

It operates in the uncrowded 801 ? 805, 863 ? 865 MHz UHF frequency range





In that case the antenna should be about 3 1/4 to 3 1/2 inches long. If
you are using wire that is insulated, just make it 3 1/4 inches.

That is probably close to the origional length.

That makes it a 1/4 of an electrical wavelength long.

For a low power short range piece of equipment, I doubt it makes much
difference on how long it is, from 3 inchs to a foot long.

It could be a coaxial type full wave.

Greg

Meant 1/2 wave.

Greg

 

[Gareth Magennis]

"Phil Allison" wrote in message
news:2750eec0-a130-4e4b-8b69-9a69ca1edb1b@googlegroups.com...

Gareth Magennis wrote:

-----------------------

Well a piece of wire worked a treat.

With a bit of heatshrink for strain relief at the transmitter end and
another on the end of the tail, it even looks like a proper one.

** So now you know how to make a "rat tail" antenna.

Thanks to all for the calculations and info.

** 300 / MHz = wavelength in metres, is worth remembering.


FYI:

That AG-1 unit is about as basic as UHF FM links get, so has limited useful
range and is prone to signal drops out due to multipath interference. The Tx
signal can almost cancel itself after reflecting off objects and surfaces
and then arriving at the Rx.

Better models have twin channel receivers, with two separated antennas,
operating as a diversity pair that helps greatly to eliminate such drop
outs.



..... Phil



******************************************


Presumably the transmitter antenna should be straight for best efficiency.

If it is (worst case scenario) a semicircle, what changes?


Gareth.

 

[Phil Allison]

Gareth Magennis wrote:

-----------------------

Well a piece of wire worked a treat.

With a bit of heatshrink for strain relief at the transmitter end and
another on the end of the tail, it even looks like a proper one.



** So now you know how to make a "rat tail" antenna.


Thanks to all for the calculations and info.


** 300 / MHz = wavelength in metres, is worth remembering.


FYI:

That AG-1 unit is about as basic as UHF FM links get, so has limited useful
range and is prone to signal drops out due to multipath interference. The Tx
signal can almost cancel itself after reflecting off objects and surfaces
and then arriving at the Rx.

Better models have twin channel receivers, with two separated antennas,
operating as a diversity pair that helps greatly to eliminate such drop
outs.



Presumably the transmitter antenna should be straight for best efficiency.

If it is (worst case scenario) a semicircle, what changes?

** Every effort should be made to straighten it !

It's an FM signal, so the recovered audio is not affected until the RF level becomes very weak. Meaning there is usually plenty in reserve to allow for circumstances that reduce the RF level compared to free field.

Players buy units like this not to get long range, but merely to be free of that damn instrument cable.


..... Phil